Datasheet

ManualsBrandsST ManualsDC / DC Adjustable Switching RegulatorsSwitching Voltage RegulatorSwitching Regulator/Step-down Regulator Multiwatt 4A

L296

L296P

April 1993

HIGH CURRENT SWITCHING REGULATORS

.4 A OUTPUT CURRENT

.5.1 V TO 40 V OUTPUT VOLTAGERANGE

.0 TO 100 % DUTY CYCLE RANGE

.PRECISE (±2 %) ON-CHIP REFERENCE

.SWITCHING FREQUENCY UP TO 200 KHz

.VERY HIGH EFFICIENCY (UP TO 90 %)

.VERY FEW EXTERNAL COMPONENTS

.SOFT START

.RESET OUTPUT

.EXTERNAL PROGRAMMABLE LIMITING

CURRENT (L296P)

.CONTROL CIRCUIT FOR CROWBAR SCR

.INPUT FOR REMOTE INHIBIT AND

SYNCHRONUS PWM

.THERMAL SHUTDOWN

DESCRIPTION

The L296andL296Pare stepdownpower switching

regulators delivering 4 A at a voltage variable from

5.1 V to 40 V.

Featuresof the devicesincludesoft start,remote in-

hibit, thermal protection, a reset output for micro-

processors and a PWM comparator input for syn-

chronization in multichip configurations.

The L296Pincudesexternal programmable limiting

current.

The L296 and L296Pare mounted in a 15-leadMul-

tiwatt plasticpowerpackageandrequiresveryfew

external components.

Efficient operation at switching frequencies up to

200 KHz allows a reduction in the size and cost of

external filter components. A voltage sense input

and SCR drive output are provided for optional

crowbar overvoltage protection with an external

SCR.

Multiwatt



(15 lead)

ORDERING NUMBERS :

L296 (Vertical) L296HT (Horizontal)

L296P (Vertical) L296PHT (Horizontal)

PIN CONNECTION (top view)

1/21

Summary of content (199 pages)

PAGE 1
L296 L296P HIGH CURRENT SWITCHING REGULATORS .. .. .. .. .. .. . 4 A OUTPUT CURRENT 5.
PAGE 2
L296 - L296P PIN FUNCTIONS N° 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Name CROWBAR INPUT Function Voltage Sense Input for Crowbar Overvoltage Protection. Normally connected to the feedback input thus triggering the SCR when V out exceeds nominal by 20 %. May also monitor the input and a voltage divider can be added to increase the threshold. Connected to ground when SCR not used. OUTPUT Regulator Output SUPPLY VOLTAGE Unrergulated Voltage Input. An internal Regulator Powers the L296s Internal Logic.
PAGE 3
L296 - L296P CIRCUIT OPERATION (refer to the block diagram) The L296 and L296P are monolithic stepdown switching regulators providing output voltages from 5.1V to 40V and delivering 4A. The regulationloop consists of a sawtooth oscillator, error amplifier, comparator and the output stage. An error signal is produced by comparing the output voltage with a precise 5.1V on-chip reference (zener zap trimmed to ± 2 %).
PAGE 4
L296 - L296P Figure 2 : Soft Start Waveforms Figure 3 : Current Limiter Waveforms ABSOLUTE MAXIMUM RATINGS Symbol Vi Vi – V2 Value Unit 50 V Input to Output Voltage Difference 50 V Output DC Voltage Output Peak Voltage at t = 0.1 µsec f = 200KHz –1 –7 V V Voltage at Pins 1, 12 10 V Voltage at Pin 15 15 V Voltage at Pins 4, 5, 7, 9 and 13 5.
PAGE 5
L296 - L296P THERMAL DATA Symbol Parameter Value Unit Rth j-case Thermal Resistance Junction-case Max. 3 °C/W Rth j-amb Thermal Resistance Junction-ambient Max. 35 °C/W ELECTRICAL CHARACTERISTICS (refer to the test circuits T j = 25oC, Vi = 35V, unless otherwise specified) Symbol Parameter Test Conditions Min. Typ. Max. Unit Fig.
PAGE 6
L296 - L296P ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter Test Conditions Min. Typ. Max. Unit Fig. SOFT START I5 so Source Current V6 = 0V, V 5 = 3V 80 130 150 µA 6b I5 si Sink Current V6 = 3V, V 5 = 3V 50 70 120 µA 6b Input Voltage Low Level High Level Vi = 9V to 46V, V7 = 0V, S1 : B, S2 : B V 6a V6L V6H Vi = 9V to 46V, V7 = 0V, S1 : B, S2 : B V6 = 0.8V V6 = 2V µA 6a – I6L – I6H Input Current with Input Voltage Low Level High Level V 6c V 6c INHIBIT – 0.
PAGE 7
L296 - L296P Figure 4 : Dynamic Test Circuit C7, C8 : EKR (ROE) L1 : L = 300 µH at 8 A Core type : MAGNETICS 58930 - A2 MPP N° turns : 43 Wire Gauge : 1 mm (18 AWG) COGEMA 946044 (*) Minimum suggested value (10 µF) to avoid oscillations. Ripple consideration leads to typical value of 1000 µF or higher. Figure 5 : PC.
PAGE 8
L296 - L296P Figure 6 : DC Test Circuits. Figure 6a. Figure 6b. Figure 6c. 1 - Set V10 FOR V9 = 1 V 2 - Change V10 to obtain V9 = 3 V 3 - GV = DV9 ∆V10 Figure 6d.
PAGE 9
L296 - L296P Figure 7 : Quienscent Drain Current vs. Supply Voltage (0 % Duty Cycle - see fig. 6a). Figure 8 : Quienscent Drain Current vs. Supply Voltage (100 % Duty Cycle see fig. 6a). Figure 9 : Quiescent Drain Current vs. Junction Temperature (0 % Duty Cycle see fig. 6a). Figure 10 : Quiescent Drain Current vs. Junction Temperature (100 % Duty Cycle see fig. 6a). Figure 11 : Reference Voltage (pin 10) vs. VI (see fig. 4). Figure 12 : Reference Voltage (pin 10) vs. Junction Temperature (see fig. 4).
PAGE 10
L296 - L296P Figure 13 : Open Loop Frequency and Phase Response of Error Amplifier (see fig. 6c). Figure 14 : Switching Frequency vs. Input Voltage (see fig. 4). Figure 15 : Switching Frequency vs. Junction Temperature (see fig. 4). Figure 16 : Switching Frequency vs. R1 (see fig. 4). Figure 17 : Line Transient Response (see fig. 4). Figure 18 : Load Transient Response (see fig. 4).
PAGE 11
L296 - L296P Figure 19 : Supply Voltage Ripple Rejection vs. Frequency (see fig. 4). Figure 20 : Dropout Voltage Between Pin 3 and Pin 2 vs. Current at Pin 2. Figure 21 : Dropout Voltage Between Pin 3 and Pin 2 vs. Junction Temperature. Figure 22 : Power Dissipation Derating Curve. Figure 23 : Power Dissipation (device only) vs. Input Voltage. Figure 24 : Power Dissipation (device only) vs. Input voltage.
PAGE 12
L296 - L296P Figure 25 : Power Dissipation (device only) vs. Output Voltage (see fig. 4). Figure 26 : Power Dissipation (device only) vs. Output Voltage (see fig. 4). Figure 27 : Voltageand Current Waveforms at Pin 2 (see fig. 4). Figure 28 : Efficiency vs. Output Current. Figure 29 : Efficiency vs. Output Voltage. Figure 30 : Efficiency vs. Output Voltage.
PAGE 13
L296 - L296P Figure 31 : Current Limiting Threshold vs. Rpin 4 (L296P only). Figure 32 : Current Limiting Threshold vs. Junction Temperature. Figure 33 : Current Limiting Threshold vs. Supply Voltage.
PAGE 14
L296 - L296P APPLICATION INFORMATION Figure 34 : Typical Application Circuit. (*) Minimum value (10 µF) to avoid oscillations ; ripple consideration leads to typical value of 1000 µF or higher L1 : 58930 - MPP COGEMA 946044 ; GUP 20 COGEMA 946045 SUGGESTED INDUCTOR (L1) Core Type Magnetics 58930 – A2MPP Thomson GUP 20 x 16 x 7 Siemens EC 35/17/10 (B6633& – G0500 – X127) VOGT 250 µH Toroidal Coil, Part Number 5730501800 V0 12 V 15 V 18 V 24 V 14/21 No Turns 43 65 40 Wire Gauge 1.0 mm 0.8 mm 2 x 0.
PAGE 15
L296 - L296P Figure 35 : P.C. Board and Component Layout of the Circuit of fig. 34 (1:1 scale) SELECTION OF COMPONENT VALUES (see fig. 34) Component Recommended Value R1 R2 – 100 kΩ Set Input Voltage Threshold for Reset. R3 R4 4.3 kΩ 10 kΩ Sets Switching Frequency Pull-down Resistor R5 R6 15 kΩ Frequency Compensation Collector Load For Reset Output R7 R8 – 4.7 kΩ Divider to Set Output Voltage Riim – C1 C2 C3 C4 Purpose Allowed Rage Notes Min. Max.
PAGE 16
L296 - L296P Figure 36 : A Minimal 5.1 V Fixed Regulator. Very Few Components are Required. Figure 37 : 12 V/10 A Power Supply.
PAGE 17
L296 - L296P Figure 38 : Programmable Power Supply. V o = 5.1 to 15 V I o = 4 A max. (min. load current = 100 mA) ripple ≤ 20 mV load regulation (1 A to 4 A) = 10 mV (V o = 5.1 V) line regulation (220 V ± 15 % and to I o = 3 A) = 15 mV (V o = 5.1 V) Figure 39 : Preregulator for Distributed Supplies. (*) L2 and C2 are necessary to reduce the switching frequency spikes.
PAGE 18
L296 - L296P Figure 40 : In Multiple Supplies Several L296s can be Synchronized As Shown. Figure 41 : Voltage Sensing for Remote Load. Figure 42 : A 5.1 V/15 V/24 V Multiple Supply. Note the Synchronization of the Three L296s.
PAGE 19
L296 - L296P Figure 43 : 5.1V/2A Power Supply using External Limiting Current Resistor and Crowbar Protection on the Supply Voltage (L296P only) SOFT-START AND REPETITIVE POWER-ON When the device is repetitivelypowered-on,the softstart capacitor, CSS, must be discharged rapidly to ensurethat each start is ”soft”. This can be achieved economicallyusing thereset circuit, as shownin Figure 44.
PAGE 20
L296 - L296P MULTIWATT15 VERTICAL PACKAGE MECHANICAL DATA Millimeters Typ. Max. 5 2.65 1.6 Min. 0.55 0.75 1.4 17.91 0.019 0.026 0.045 0.692 0.772 1 0.49 0.66 1.14 17.57 19.6 22.1 22 17.65 17.25 10.3 2.65 4.2 4.5 1.9 1.9 3.65 1.27 17.78 17.5 10.7 4.3 5.08 Inches Typ. Max. 0.197 0.104 0.063 0.039 20.2 22.6 22.5 18.1 17.75 10.9 2.9 4.6 5.3 2.6 2.6 3.85 0.870 0.866 0.695 0.679 0.406 0.104 0.165 0.177 0.075 0.075 0.144 0.050 0.700 0.689 0.421 0.169 0.200 0.022 0.030 0.055 0.705 0.795 0.890 0.
PAGE 21
L296 - L296P Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 22
L4960 2.5A POWER SWITCHING REGULATOR 2.5A OUTPUT CURRENT 5.1V TO 40V OPUTPUT VOLTAGE RANGE PRECISE (± 2%) ON-CHIP REFERENCE HIGH SWITCHING FREQUENCY VERY HIGH EFFICIENCY (UP TO 90%) VERY FEW EXTERNAL COMPONENTS SOFT START INTERNAL LIMITING CURRENT THERMAL SHUTDOWN DESCRIPTION The L4960 is a monolithic power switching regulator delivering 2.5A at a voltage variable from 5V to 40V in step down configuration.
PAGE 23
L4960 PIN CONNECTION (Top view) ABSOLUTE MAXIMUM RATINGS Symbol V1 V1 - V7 V7 V3 , V6 V2 I3 I5 Ptot Tj, Tstg Parameter Input voltage Input to output voltage difference Negative output DC voltage Negative output peak voltage at t = 0.1µs; f = 100KHz Voltage at pin 3 and 6 Voltage at pin 2 Pin 3 sink current Pin 5 source current Power dissipation at Tcase ≤ 90°C Junction and storage temperature Value 50 50 -1 -5 5.
PAGE 24
L4960 THERMAL DATA Symbol Parameter Value Unit R th j-case Thermal resistance junction-case max 4 °C/W R th j-amb Thermal resistance junction-ambient max 50 °C/W ELECTRICAL CHARACTERISTICS (Refer to the test circuit, T j = 25 °C, Vi = 35V, unless otherwise specified) Symbol Parameter Test Conditions Min. Typ. Max. Unit Vref 40 V 9 46 V DYNAMIC CHARACTERISTICS Vo Output voltage range Vi = 46V Io = 1A Vi Input voltage range Vo = Vref to 36V Io = 2.
PAGE 25
L4960 ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter Test Conditions Min. Typ. Max. Unit 30 40 mA 15 20 mA 1 mA DC CHARACTERISTICS I1Q Quiescent drain current 100% duty cycle pins 5 and 7 open Vi = 46V 0% duty cycle -I7L Output leakage current 0% duty cycle SOFT START I6SO Source current 100 140 180 µA I6SI Sink current 50 70 120 µA ERROR AMPLIFIER 3.5 V V3H High level output voltage V2 = 4.7V I3 = 100µA V3L Low level output voltage V2 = 5.
PAGE 26
L4960 CIRCUIT OPERATION (refer to the block diagram) The L4960 is a monolithic stepdown switching regulator providing output voltages from 5.1V to 40V and delivering 2.5A. The regulation loop consists of a sawtooth oscillator, error amplifier, comparator and the output stage. An error signal is produced by comparing the output voltage with a precise 5.1V on-chip reference (zener zap trimmed to ± 2%).
PAGE 27
L4960 Figure 3. Test and application circuit C6, C7: EKR (ROE) L1 = 150µH at 5A (COGEMA 946042) CORE TYPE: MAGNETICS 58206-A2 MPP N° TURNS 45, WIRE GAUGE: 0.8mm (20 AWG) Figure 4. Quiescent drain current vs. supply voltage (0% duty cycle) 6/15 Figure 5. Quiescent drain current vs. supply voltage (100% duty cycle) Figure 6. Quiescent drain current vs.
PAGE 28
L4960 Figure 7. Quiescent drain current vs . junction temperature (100% duty cycle) Figure 8. Reference voltage (pin 2) vs. Vi Figure 9. Reference voltage versus junction temperature (pin 2) Figure 10. Open loop frequency and phase responde of error amplifier Fig ure 11. Switc hing frequency vs. input voltage Figur e 12 . Sw itching frequency vs. j unc tion te mperature Fi gur e 13 . Switching frequency vs. R2 (see test circuit) Fig ure 1 4. Line transie nt response Fig ure 15.
PAGE 29
L4960 Figure 16. Supply voltage ripple rejection vs. frequency Figure 17. Dropout voltage between pin 1 and pin 7 vs. current at pin 7 Figure 18. Dropout voltage be twe e n pi n 1 a nd 7 vs . junction temperature Figure 19. Power dissipation derating curve Fi gur e 2 0. E ffi ci enc y vs. output current Fi gu re 2 1. E ffic ien cy vs . output current Fi gur e 2 2. Effi ci en cy vs. output current 8/15 Fi gur e 2 3 . Effi ci ency vs.
PAGE 30
L4960 APPLICATION INFORMATION Figure 24. Typical application circuit C1, C6, C7: EKR (ROE) D1: BYW80 OR 5A SCHOTTKY DIODE SUGGESTED INDUCTOR: L 1 = 150µH at 5A CORE TYPE: MAGNETICS 58206 - A2 - MPP N° TURNS: 45, WIRE GAUGE: 0.8mm (20 AWG), COGEMA 946042 U15/GUP15: N° TURNS: 60, WIRE GAUGE: 0.8mm (20 AWG), AIR GAP: 1mm, COGEMA 969051. Figure 25. P.C. board and component layout of the Fig. 24 (1 : 1 scale) Resistor values for standard output voltages Vo R3 R4 12V 15V 18V 24V 4.7KΩ 4.7KΩ 4.7KΩ 4.
PAGE 31
L4960 APPLICATION INFORMATION Figure 26. A minimal 5.1V fixed regulator; Very few component are required * COGEMA 946042 969051 ** EKR (ROE) (TOROID CORE) (U15 CORE) Figure 27. Programmable power supply Vo = 5.1V to 15V Io = 2.5A max Load regulation (1A to 2A) = 10mV (Vo = 5.
PAGE 32
L4960 APPLICATION INFORMATION (continued) Figure 28. Microcomputer supply with + 5.
PAGE 33
L4960 APPLICATION INFORMATION (continued) Figure 29. DC-DC converter 5.1V/4A, ± 12V/2.5A; a suggestion how to synchronize a negative output L1, L3 = COGEMA 946042 (969051) L2 = COGEMA 946044 (946045) D1, D2, D3 = BYW80 Figure 30.
PAGE 34
L4960 APPLICATION INFORMATION (continued) Figure 31. Regulator for distributed supplies MOUNTING INSTRUCTION The power dissipatedin the circuit must be removed by adding an external heatsink. Thanks to the Heptawatt package attaching the hetsink is very simple, a screw or a compression spring (clip) being sufficient. Between the heatsink and the package it is better to insert a layer of silicon grease, to optimize the thermal contact, no electrical isolation is needed between the two surfaces. Figure 32.
PAGE 35
L4960 HEPTAWATT PACKAGE MECHANICAL DATA mm DIM. MIN. TYP. MAX. MIN. TYP. MAX. A 4.8 0.189 C 1.37 0.054 D 2.4 2.8 0.094 0.110 D1 1.2 1.35 0.047 0.053 E 0.35 0.55 0.014 0.022 F 0.6 0.8 0.024 F1 0.031 0.9 0.035 G 2.41 2.54 2.67 0.095 0.100 0.105 G1 4.91 5.08 5.21 0.193 0.200 0.205 G2 7.49 7.62 7.8 0.295 0.300 0.307 H2 H3 10.4 10.05 10.4 0.409 0.396 0.409 L 16.97 0.668 L1 14.92 0.587 L2 21.54 0.848 L3 22.62 0.891 L5 2.6 3 0.102 0.
PAGE 36
L4960 Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 37
L4962 1.5A POWER SWITCHING REGULATOR 1.5A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE PRECISE (± 2%) ON-CHIP REFERENCE HIGH SWITCHING FREQUENCY VERY HIGH EFFICIENCY (UP TO 90%) VERY FEW EXTERNAL COMPONENTS SOFT START INTERNAL LIMITING CURRENT THERMAL SHUTDOWN DESCRIPTION The L4962 is a monolithic power switching regulator delivering 1.5A at a voltage variable from 5V to 40V in step down configuration.
PAGE 38
L4962 ABSOLUTE MAXIMUM RATINGS Symbol V7 V7 - V2 V2 V11, V15 Parameter Value Unit Input voltage 50 V Input to output voltage difference 50 V Negative output DC voltage -1 V Output peak voltage at t = 0.1µs; f = 100KHz -5 V Voltage at pin 11, 15 5.5 V V10 Voltage at pin 10 7 V I11 Pin 11 sink current 1 mA I14 Pin 14 source current 20 mA Ptot Power dissipation at Tpins ≤ 90°C (Powerdip) Tcase ≤ 90°C (Heptawatt) 4.
PAGE 39
L4962 PIN FUNCTIONS (cont’d) HEPTAWATT POWERDIP 4 4, 5, 12, 13 5 FUNCTION NAME GROUND Common ground terminal. 14 OSCILLATOR A parallel RC network connected to this terminal determines the switching frequency. This pin must be connected to pin 7 input when the internal oscillator is used. 6 15 SOFT START Soft start time constant. A capacitor is connected between this terminal and ground to define the soft start time constant.
PAGE 40
L4962 ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter Test Conditions Min. Typ. Max. Unit 85 100 115 KHz DYNAMIC CHARACTERISTICS (cont’d) f Switching frequency ∆f ∆ Vi Voltage stability of switching frequency Vi = 9V to 46V ∆f ∆ Tj Temperature stability of switching frequency Tj = 0°C to 125°C fmax Maximum operating switching frequency Vo = Vref Tsd Thermal shutdown junction temperature Io = 1A 120 0.
PAGE 41
L4962 CIRCUIT OPERATION (refer to the block diagram) The L4962 isa monolithic stepdownswitching regulator providing output voltages from 5.1V to 40V and delivering 1.5A. The regulation loop consists of a sawtooth oscillator, error amplifier, comparator and the output stage. An error signal is producedby comparing the output voltage with a precise 5.1V on-chip reference (zener zap trimmed to ± 2%).
PAGE 42
L4962 Figure 3. Test and application circuit (Powerdip) 1) D 1: BYW98 or 3A Schottky diode, 45V of VRRM; 2) L1: CORE TYPE - MAGNETICS 58120 - A2 MPP N° TURNS 45, WIRE GAUGE: 0.8mm (20 AWG) 3) C 6, C7: ROE, EKR 220µF 40V Figure 4. Quiescent drain current vs. supply voltage (0% duty cycle) 6/15 Figure 5. Quiescent drain current vs. supply voltage (100% duty cycle) Figure 6. Quiescent drain curr ent vs .
PAGE 43
L4962 Figure 7. Quiescent drain cur rent vs. ju nc tion temperature (100% duty cycle) Figure 8. Reference voltage (pin 10) vs. Vi rdip) vs. Vi Figure 9. Reference voltage (pin 10 ) vs. junction temperature Figure 10. Open loop frequency and phase re- sponse of error amplifier Fi gure 11. Sw itchi ng frequency vs. input voltage Fi gure 1 2. Switchi ng freque nc y vs. ju ncti on temperature Figure 1 3. Switching frequency vs. R2 (see test circuit) Fi gure 1 4. L ine tr an si ent response Figure 15 .
PAGE 44
L4962 Figure 16. Supply voltage ripple rejection vs. frequency Figure 17. Dropout voltage between pin 7 and pin 2 vs. current at pin 2 Figure 18. Dropout voltage b etwe en pi n 7 a nd 2 v s. junction temperature Fi gu re 1 9. Effi c ien cy vs. output current Fi g ure 2 0. Effi ci ency v s. output current F ig ur e 2 1. Effic i en cy vs. output current Fi gur e 2 2 . Effi ci enc y vs. output voltage Fi g ure 2 3. Effi ci ency v s. output voltage Figure 24. Maximum allowable power dissipation vs.
PAGE 45
L4962 APPLICATION INFORMATION Figure 25. Typical application circuit C1, C6, C7: EKR (ROE) D1: BYW98 OR VISK340 (SCHOTTKY) SUGGESTED INDUCTORS: (L1) = MAGNETICS 58120 - A2MPP - 45 TURNS - WIRE GAUGE 0.8mm (20AWG) COGEMA 946043 OR U15, GUP15, 60 TURNS 1mm, AIR GAP 0.8mm (20 AWG) - COGEMA 969051. Figure 26. P.C. board and component layout of the circuit of Fig. 25 (1 : 1 scale) Resistor values for standard output 7 voltages Vo R3 R4 12V 15V 18V 24V 4.7KΩ 4.7KΩ 4.7KΩ 4.7KΩ 6.2KΩ 9.
PAGE 46
L4962 APPLICATION INFORMATION (continued) Figure 27. - A minimal 5.1V fixed regulator; Very few component are required * COGEMA 946043 969051 ** EKR (ROE) (TOROID CORE) (U15 CORE) Figure 28. Programmable power supply Vo = 5.1V to 15V Io = 1.5A max Load regulation (0.5A to 1.5A) = 10mV (Vo = 5.1V) Line regulation (220V ± 15% and to Io = 1A) = 15mV (Vo = 5.
PAGE 47
L4962 APPLICATION INFORMATION (continued) Figure 29. DC-DC converter 5.1V/4A, ± 12V/1A. A suggestion how to synchronize a negative output L1, L3 = COGEMA 946043 (969051) L2 = COGEMA 946044 (946045) Figure 30. In multiple supplies several L4962s can be synchronized as shown Figure 31.
PAGE 48
L4962 MOUNTING INSTRUCTION The Rth-j-amb of the L4962 can be reduced by soldering the GND pins to a suitable copper area of the printed circuit board (Fig. 32). The diagram of figure 33 shows the Rth-j-amb as a function of the side ”l” of two equal square copper areas having the thickness of 35µ (1.4 mils). During soldering the pins temperature must not exceed 260°C and the soldering time must not be longer than 12 seconds.
PAGE 49
L4962 POWERDIP PACKAGE MECHANICAL DATA mm DIM. MIN. a1 0.51 B 0.85 b b1 TYP. inch MAX. MIN. TYP. MAX. 0.020 1.40 0.033 0.50 0.38 0.020 0.50 D 0.055 0.015 0.020 20.0 0.787 E 8.80 0.346 e 2.54 0.100 e3 17.78 0.700 F 7.10 0.280 I 5.10 0.201 L Z 3.30 0.130 1.27 0.
PAGE 50
L4962 HEPTAWATT PACKAGE MECHANICAL DATA mm DIM. MIN. TYP. A TYP. MAX. 0.189 1.37 0.054 2.4 2.8 0.094 0.110 D1 1.2 1.35 0.047 0.053 E 0.35 0.55 0.014 0.022 F 0.6 0.8 0.024 0.031 F1 0.9 0.035 G 2.41 2.54 2.67 0.095 0.100 0.105 G1 4.91 5.08 5.21 0.193 0.200 0.205 G2 7.49 7.62 7.8 0.295 0.300 H2 H3 10.4 10.05 10.4 0.396 0.409 L 16.97 0.668 14.92 0.587 L2 21.54 0.848 22.62 0.891 L5 2.6 3 L6 15.1 L7 6 M 0.102 0.118 15.8 0.594 0.622 6.
PAGE 51
L4962 Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 52
L4963 L4963D 1.5A SWITCHING REGULATOR 1.5A OUTPUT LOAD CURRENT 5.1 TO 36V OUTPUT VOLTAGE RANGE DISCONTINUOUS VARIABLE FREQUENCY MODE PRECISE (+/–2%) ON CHIP REFERENCE VERY HIGH EFFICIENCY VERY FEW EXTERNAL COMPONENTS NO FREQ. COMPENSATION REQUIRED RESET AND POWER FAIL OUTPUT FOR MICROPROCESSOR INTERNAL CURRENT LIMITING THERMAL SHUTDOWN Powerdip12+3+3 SO20 ORDERING NUMBERS: DESCRIPTION The L4963 is a monolithic power switching regulator delivering 1.5A at 5.1V. The output voltage is adjustable from 5.
PAGE 53
L4963 - L4963D ABSOLUTE MAXIMUM RATINGS Symbol Value Unit Input Voltage (pin 1 and pin 3 connected togheter) 47 V Input to Output Voltage Difference 47 V V2 Negative Output DC Voltage –1 V V2 Negative Output Peak Voltage at t=0.2 µs, f=50kHz –5 V Power Fail Input 25 V Reset and Power Fail Output Vi Reset Delay Input 5.
PAGE 54
L4963 - L4963D PIN FUNCTIONS SO20L Power DIP Name Description 1 1 SIGNAL SUPPLY VOLTAGE Must be Connected to pin 3 2 2 OUTPUT Regulator output 3 3 SUPPLY VOLTAGE Unregulated voltage input. An internal regulator powers the internal logic. 4, 5, 6, 7 14, 15, 16, 17 4, 5, 6 13, 14, 15 GROUND Common ground terminal 8 7 POWER FAIL INPUT Input of the power fail circuit. The threshold can be modified introducing an external voltage divider between the Supply Voltage and GND.
PAGE 55
L4963 - L4963D CIRCUIT DESCRIPTION (Refer to Block Diagram) The L4963 is a monolithic stepdown regulator providing 1.5A at 5.1V working in discontinuous variable frequency mode. In normal operation the device resonates at a frequency depending primarily on the inductance value, the input and output voltage and the load current. The maximum switching however can be limited by an internal oscillator, which can be programmed by only one external resistor.
PAGE 56
L4963 - L4963D ELECTRICAL CHARACTERISTIC (Refer to the test circuit Vi = 30V Tj = 25°C unless otherwise specified ) Symbol Parameter Test Condition s Min. Typ. Max. Unit Fig. Vref 36 V 2 46 V 2 5.1 5.2 V 2 5 20 µA 3a 5 10 mV 3a DYNAMIC CHARACTERISTICS Vo Output Voltage Range Vi = 46V Io = 0.5A Vi Input Voltage Range Vo = Vref to 36V Io = 0.5A 9 V12 Feedback Voltage Vi = 9 to 46V Io = 0.
PAGE 57
L4963 - L4963D ELECTRICAL CHARACTERISTIC (Continued) Symbol Parameter Test Condition s Min. Typ. Max. Unit Fig. RESET V12 Rising Threshold Voltage Vi = 9 to 46V Vref –150 Vref –100 Vref –50 mV 3b V12 Falling Threshold Voltage Vi = 9 to 46V Vref –150 Vref –200 Vref –250 mV 3b V9D Delay Rising Thereshold Voltage V7 = OPEN 4.3 4.5 4.7 V 3b V9F Delay Falling Thereshold Voltage 1 1.5 2 V 3b 110 140 µA 3b Delay Source Current V9 = 4.7V V12 = 5.
PAGE 58
L4963 - L4963D Figure 2: Test Circuit Figure 3: DC Test Circuit Figure 3a Figure 3b 7/17
PAGE 59
L4963 - L4963D Figure 3c Figure 4: Quiescent Drain Current vs. Supply Voltage (0% Duty Cycle) Figure 5: Quiescent Drain Current vs. Supply Voltage (100% Duty Cycle) Figure 6: Quiescent Drain Current vs. Junction Temperature (0% Duty Cycle) Figure 7: Quiescent Drain Current vs.
PAGE 60
L4963 - L4963D Figure 8: Reference Voltage vs. Vi Figure 9: Reference Voltage vs. Tj Figure 10: Line Transient Response Figure 11: Load Transient Figure 12: Supply Voltage Ripple Rejection vs. Frequency Figure 13: Dropout Voltage Between pi3 and 2 vs.
PAGE 61
L4963 - L4963D Figure 14: Dropout Voltage Between pin3 and 2 vs. Junction Temperature Figure 15: Maximum Allowable PowerDissipation vs. Ambient Temperature (Powerdip Package Only) Figure 16: Power Dissipation (device only) vs. Input Voltage (Powerdip Package Only) Figure 17: Power Dissipation (device only) vs. Output Voltage (Powerdip Package Only) Figure 18: Voltage and Current Waveform at pin2 Figure 19: Efficiency vs.
PAGE 62
L4963 - L4963D Figure 20: Efficiency vs. Output Voltage (Powerdip Package Only) Figure 21: Current Limit vs. Junction Temperature Vi = 30V Figure 22: Current Limit vs. Input Voltage Figure 23: Oscillator Frequency vs. R2 (see fig. 26) Figure 24: Oscillator Frequency vs. Junction Temperature Figure 25: Oscillator Frequency vs.
PAGE 63
L4963 - L4963D Figure 26: Evaluation Board Circuit PART LIST CAPACITOR Resistor Values for Standard Output Voltages C1 1000µF 50V EKR (*) VO R6 R5 C2 2.2mF 16V 12 4.7KΩ 6.2KΩ C3 1000µF 40V with low ESR 15 4.7KΩ 9.1KW C4 1µF 50V film 18 4.7KΩ 12KW 24 4.7KΩ 18KW RESISTOR R1 1KΩ R2 51KΩ R3 1KΩ R4 1KΩ R5, R6 Diode: BYW98 Core: L = 40µH Magnetics58121-A2MPP34 Turns 0.
PAGE 64
L4963 - L4963D Figure 27: P.C. Board and Component Layout of the Circuit of fig. 26 (Powerdip Package) (1:1 scale). Figure 28: Thermal Characteristics Figure 29: Junction to Ambient Thermal Resistance vs.
PAGE 65
L4963 - L4963D Figure 30: A Minimal 5.
PAGE 66
L4963 - L4963D POWERDIP18 PACKAGE MECHANICAL DATA mm inch DIM. MIN. a1 0.51 B 0.85 b b1 TYP. MAX. MIN. TYP. MAX. 0.020 1.40 0.033 0.50 0.38 0.020 0.50 D 0.055 0.015 0.020 24.80 0.976 E 8.80 0.346 e 2.54 0.100 e3 20.32 0.800 F 7.10 0.280 I 5.10 0.201 L Z 3.30 0.130 2.54 0.
PAGE 67
L4963 - L4963D SO20 PACKAGE MECHANICAL DATA mm DIM. MIN. TYP. A a1 inch MAX. TYP. 2.65 0.1 MAX. 0.104 0.3 a2 0.004 0.012 2.45 0.096 b 0.35 0.49 0.014 0.019 b1 0.23 0.32 0.009 0.013 C 0.5 0.020 c1 45 (typ.) D 12.6 13.0 0.496 0.512 E 10 10.65 0.394 0.419 e 1.27 0.050 e3 11.43 0.450 F 7.4 7.6 0.291 0.299 L 0.5 1.27 0.020 0.050 M S 16/17 MIN. 0.75 0.030 8 (max.
PAGE 68
L4963 - L4963D Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 69
L4970A 10A SWITCHING REGULATOR 10A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE 0 TO 90% DUTY CYCLE RANGE INTERNAL FEED-FORWARD LINE REGULATION INTERNAL CURRENT LIMITING PRECISE 5.
PAGE 70
L4970A ABSOLUTE MAXIMUM RATINGS Symbol Value Unit V9 Input Voltage Parameter 55 V V9 Input Operating Voltage 50 V V7 Output DC Voltage Output Peak Voltage at t = 0.
PAGE 71
L4970A PIN FUNCTIONS o N Name Function 1 OSCILLATOR Rosc. External resistor connected to ground determines the constant charging current of C osc. 2 OSCILLATOR Cosc. External capacitor connected to ground determines (with R osc) the switching frequency. 3 RESET INPUT Input of Power Fail Circuit. The threshold is 5.1V. It may be connected via a divider to the input for power fail function. It must be connected to the pin 14 an external 30KΩ resistor when power fail signal not required.
PAGE 72
L4970A Figure 1: Feedforward Waveform Figure 2: Soft Start Function Figure 3: Limiting Current Function 4/21
PAGE 73
L4970A stability of the loop can be adjusted by an external RC network connected to the output of the error amplifier. A voltage feedforward control has been added to the oscillator, this maintains superior line regulation over a wide input voltage range. Closing the loop directly gives an output voltage of 5.1V, higher voltages are obtained by inserting a voltage divider. At turn on output overcurrents are prevented by the soft start function (fig. 2).
PAGE 74
L4970A ELECTRICAL CHARACTERISTICS (Refer to the test circuit, Tj = 25°C, Vi = 35V, R4 = 16KΩ, C9 = 2.2nF, fSW = 200KHz typ, unless otherwise specified) DYNAMIC CHARACTERISTICS Symbol Parameter Test Condition Min. Vi input Voltage Range (pin 9) Vo = Vref to 40V Io = 10A 15 Vo Output Votage Vi = 15V to 50V Io = 5A; Vo = Vref 5 ∆Vo Line Regulation Vi = 15V to 50V Io = 5A; Vo = Vref ∆Vo Load Regulation Vo = Vref Io = 3A to 6A Io = 2A to 10A Typ. Max. Unit Fig. 50 V 5 5.1 5.
PAGE 75
L4970A ELECTRICAL CHARACTERISTICS (continued) DC CHARACTERISTICS Symbol Parameter V9on Turn-on Threshold V9 Hyst Turn-off Hysteresys Test Condition Min. Typ. Max. Unit Fig. 10 11 12 V 7A V 7A I9Q Quiescent Current V12 = 0; S1 = D 13 19 mA 7A I9OQ Operating Supply Current V12 = 0; S1 = C; S2 = B 16 23 mA 7A Out Leak Current Vi = 55V; S3 = A; V12 = 0 2 mA 7A Fig.
PAGE 76
L4970A ELECTRICAL CHARACTERISTICS (continued) RESET AND POWER FAIL FUNCTIONS Symbol Parameter Min. Typ. Max. Unit Fig. V11R Rising Threshold Voltage (pin 11) Vi = 15 to 50V V3 = 5.3V Test Condition Vref –120 Vref –100 Vref –80 V mV 7D V11F Falling Threshold Voltage (pin 11) Vi = 15 to 50V V3 = 5.3V 4.77 Vref –200 Vref –160 V mV 7D V5H Delay High Threshold Voltage Vi = 15 to 50V V14 = V11 V3 = 5.3V 4.95 5.1 5.
PAGE 77
L4970A Figure 6a: P.C. Board (components side) and Components Layout of Figure 5 (1:1 scale). PARTS LIST Table A R1 = 30KΩ C 1, C2 = 3300µF 63VL EYF (ROE R2 = 10KΩ C 3, C4, C5, C6 = 2.2µF R3 = 15KΩ C 7 = 390pF Film R4 = 16KΩ C 8 = 22nF MKT 1817 (ERO) R5 = 22Ω 0,5W R6 = 4K7 C 9 = 2.2nF KP1830 R7 = 10Ω C 10 = 220nF MKT R8 = see tab. A C 11 = 2.2nF MP1830 R9 = OPTION **C12 , C13, C14 = 220µF 40VL EKR R10 = 4K7 C 15 = 1µF Film V0 R9 R7 12V 15V 18V 24V 4.7kΩ 4.7kΩ 4.7kΩ 4.7kΩ 6.2kW 9.
PAGE 78
L4970A Figure 6b: P.C. Board (Back side) and Components Layout of the Circuit of Fig. 5.
PAGE 79
L4970A Figure 7A Figure 7B 11/21
PAGE 80
L4970A Figure 7D Figure 7C 12/21
PAGE 81
L4970A Figure 8: Quiescent Drain Current vs. Supply Voltage (0% duty cycle - see fig. 7A). Figure 9: Quiescent Drain Current vs. Junction Temperature (0% duty cycle). Figure 10: Quiescent Drain Current vs. Duty Cycle Figure 11: Reference Voltage (pin14) vs. Vi (see fig. 7) Figure 12: Reference Voltage (pin 14) vs. Junction Temperature (see fig. 7) Figure 13: Reference Voltage (pin15) vs. Vi (see fig.
PAGE 82
L4970A Figure 14: Reference Voltage (pin 15) vs. Junction Temperature (see fig. 7) Figure 15: Reference Voltage 5.1V (pin 14) Supply Voltage Ripple Rejection vs. Frequency Figure 16: Switching Frequency vs. Input Voltage (see fig. 5) Figure 17: Switching Frequency vs. Junction Temperature (see fig 5) Figure 18: Switching Frequency vs. R4 (see fig. 5) Figure 19: Max. Duty Cycle vs.
PAGE 83
L4970A Figure 20: Supply Voltage Ripple Rejection vs. Frequency (see fig. 5) Figure 21: Line Transient Response (see fig. 5) Figure 22: Load Transient Response (see fig. 5) Figure 23: Dropout Voltage Between Pin 9 and Pin 7 vs. Current at Pin 7 Figure 24: Dropout Voltage Between Pin 9 and Pin 7 vs. Junction Temperature Figure 25: Power Dissipation (device only) vs.
PAGE 84
L4970A Figure 26: Power Dissipation (device only) vs. Output Voltage Figure 27: Heatsink Used to Derive the Device’s Power Dissipation Tcase − Tamb Rth - Heatsink = Pd Figure 28: Efficiency vs. Output Current Figure 29: Efficiency vs. Output Voltage Figure 30: Efficiency vs. Output Voltage 16/21 Figure 31: Open Loop Frequency and Phase Response of Error Amplifier (see fig.
PAGE 85
L4970A Figure 32: Power Dissipation Derating Curve Figure 33: A5.1V/12V Multiple Supply.
PAGE 86
L4970A Figure 34: 5.1V / 10A Low Cost Application Figure 35: 10A Switching Regulator, Adjustable from 0V to 25V.
PAGE 87
L4970A Figure 36: L4970A’sSync.
PAGE 88
L4970A MULTIWATT15 PACKAGE MECHANICAL DATA DIM. mm MIN. TYP. MAX. MIN. TYP. MAX. A 5 0.197 B 2.65 0.104 C 1.6 0.063 D 1 0.039 E 0.49 0.55 0.019 F 0.66 0.75 0.026 G 1.14 1.27 1.4 0.045 0.050 0.055 G1 17.57 17.78 17.91 0.692 0.700 0.705 H1 19.6 L 0.022 0.030 0.772 H2 20/21 inch 20.2 0.795 22.1 22.6 0.870 0.890 L1 22 22.5 0.866 0.886 L2 17.65 18.1 0.695 L3 17.25 17.5 17.75 0.679 0.689 L4 10.3 10.7 10.9 0.406 0.421 L7 2.65 2.9 0.
PAGE 89
L4970A Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 90
L4972A L4972AD 2A SWITCHING REGULATOR .. .. .. .. . . .. .. 2A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE 0 TO 90% DUTY CYCLE RANGE INTERNAL FEED-FORWARD LINE REG. INTERNAL CURRENT LIMITING PRECISE 5.
PAGE 91
L4972A-L4972AD ABSOLUTE MAXIMUM RATINGS Symbol Value Unit V11 Input Voltage Parameter 55 V V11 Input Operating Voltage 50 V V20 Output DC Voltage Output Peak Voltage at t = 0.
PAGE 92
L4972A-L4972AD PIN FUNCTIONS N o Name Fun ction 1 BOOTSTRAP A Cboot capacitor connected between this terminal and the output allows to drive properly the internal D-MOS transistor. 2 RESET DELAY A Cd capacitor connected between this terminal and ground determines the reset signal delay time. 3 RESET OUT Open Collector Reset/power Fail Signal Output. This output is high when the supply and the output voltages are safe. 4 RESET INPUT Input of Power Fail Circuit. The threshold is 5.1V.
PAGE 93
L4972A-L4972AD CIRCUIT OPERATION The L4972A is a 2A monolithic stepdown switching regulatorworking in continuousmode realized in the new BCD Technology. This technology allows the integration of isolated vertical DMOS power transistors plus mixed CMOS/Bipolar transistors. The device can deliver 2A at an output voltage adjustable from 5.1V to 40V and contains diagnostic and control functions that make it particularly suitable for microprocessor based systems.
PAGE 94
L4972A-L4972AD Figure 1 : Feedforward Waveform. Figure 2 : Soft Start Function. Figure 3 : Limiting Current Function.
PAGE 95
L4972A-L4972AD Figure 4 : Reset and Power Fail Functions.
PAGE 96
L4972A-L4972AD ELECTRICAL CHARACTERISTICS (refer to the test circuit, TJ = 25°C, Vi = 35V, R4 = 30KΩ, C9 = 2.7nF, fSW = 100KHz typ, unless otherwise specified) DYNAMIC CHARACTERISTICS Symbol Parameter Vi Input Volt. Range (pin 11) Vo = Vref to 40V Io = 2A (**) 15 Max. Un it F ig. 50 V 5 Vo Output Voltage Vi =15V to 50V Io = 1A; V o = Vref 5 5.1 5.2 V 5 ∆Vo Line Regulation Vi = 15V to 50V Io = 0.5A; Vo = Vref 12 30 mV ∆Vo Load Regulation Vo = Vref Io = 0.
PAGE 97
L4972A-L4972AD ELECTRICAL CHARACTERISTICS (continued) DC CHARACTERISTICS Symbol Parameter V11on Turn-on Threshold V11 Hyst Turn-off Hysteresys I11Q Quiescent Current I11OQ I20L Test Cond ition Min. T yp. Max. Unit Fig . 10 11 12 V 7A 1 V 7A V8 = 0; S1 = D 13 19 mA 7A Operating Supply Current V8 = 0; S1 = B; S2 = B 16 23 mA 7A Out Leak Current Vi = 55V; S3 = A; V8 = 0 2 mA 7A Fig .
PAGE 98
L4972A-L4972AD ELECTRICAL CHARACTERISTICS (continued) RESET AND POWER FAIL FUNCTIONS Symbol Min. Typ. Max. Un it F ig. V9R Rising Thereshold Voltage (pin 9) Vi = 15 to 50V V4 = 5.3V Vref -130 Vref -100 Vref -80 V mV 7D V9F Falling Thereshold Voltage (pin 9) Vi = 15 to 50V V4 = 5.3V 4.77 Vref -200 Vref -160 V mV 7D V2H Delay High Threshold Volt. Vi = 15 to 50V V4 = 5.3V V9 = V13 4.95 5.1 5.25 V 7D V2L Delay Low Threshold Volt. Vi = 15 to 50V V4 = 4.7V V9 = V13 1 1.1 1.
PAGE 99
L4972A-L4972AD Figure 6a : Component Layout of fig.5 (1 : 1 scale). Evaluation Board Available (only for DIP version) PART LIST R1 = 30KΩ R2 = 10KΩ R3 = 15KΩ R4 = 30KΩ R5 = 22Ω R6 = 4.7KΩ R7 = see table A R8 = OPTION R9 = 4.7KΩ * C1 = C2 = 1000µF 63V EYF (ROE) C3 = C4 = C 5 = C 6 = 2,2µF 50V C7 = 390pF Film C8 = 22nF MKT 1837 (ERO) C9 = 2.7nF KP 1830 (ERO) C10 = 0.
PAGE 100
L4972A-L4972AD Figure 6b: P.C. Board and Component Layout of the Circuit of Fig. 5. (1:1 scale) Figure 7 : DC Test Circuits.
PAGE 101
L4972A-L4972AD Figure 7A. Figure 7B. Figure 7C.
PAGE 102
L4972A-L4972AD Figure 7D. Figure 8 : Quiescent Drain Current vs. Supply Voltage (0% duty cycle - see fig. 7A). Figure 9 : Quiescent Drain Current vs. Junction Temperature (0% duty cycle).
PAGE 103
L4972A-L4972AD Figure 10 : Quiescent Drain Current vs. Duty Cycle. Figure 11 : Reference Voltage (pin 13) vs. Vi (see fig. 7). Figure 12 : Reference Voltage (pin 13) vs. Junction Temperature (see fig. 7). Figure 13 : Reference Voltage (pin 14) vs. Vi (see fig. 7). Figure 14 : Reference Voltage (pin 14) vs. Junction Temperature (see fig. 7). Figure 15 : Reference Voltage 5.1V (pin 13) Supply Voltage Ripple Rejection vs.
PAGE 104
L4972A-L4972AD Figure 16 : Switching Frequency vs. Input Voltage (see fig. 5). Figure 17 : Switching Frequency vs. Junction Temperature (see fig. 5). Figure 18 : Switching Frequency vs. R4 (see fig.5). Figure 19 : Maximum Duty Cycle vs. Frequency. Figure 20 : Supply Voltage Ripple Rejection vs. Frequency (see fig. 5). Figure 21 : Efficiency vs. Output Voltage.
PAGE 105
L4972A-L4972AD Figure 22 : Line Transient Response (see fig. 5). Figure 23 : Load Transient Response (see fig. 5). Figure 24 : Dropout Voltage between Pin 11 and Pin 20 vs. Current at Pin 20. Figure 25 : .Dropout Voltage between Pin 11 and Pin 20 vs. Junction Temperature. Figure 26 : Power Dissipation (device only) vs. Input Voltage. Figure 27 : Power Dissipation (device only) vs. Input Voltage.
PAGE 106
L4972A-L4972AD Figure 28 : Power Dissipation (device only) vs. Output Voltage. Figure 29 : Power Dissipation (device only) vs. Output Voltage. Figure 30 : Power Dissipation (device only) vs. Output Current. Figure 31 : Power Dissipation (device only) vs. Output Current. Figure 32 : Efficiency vs. Output Current. Figure 33 : Test PCB Thermal Characteristic.
PAGE 107
L4972A-L4972AD Figure 34 : Junction to Ambient Thermal Resistance vs. Area on Board Heatsink (DIP 16+2+2) Figure 35: Junction to Ambient Thermal Resistance vs. Area on Board Heatsink (SO20) Figure 36: Maximum Allowable Power Dissipation vs. Ambient Temperature (Powerdip) Figure 37: Maximum Allowable Power Dissipation vs. Ambient Temperature (SO20) Figure 38: Open Loop Frequency and Phase of Error Amplifier (see fig. 7C).
PAGE 108
L4972A-L4972AD Figure 39 : 2A – 5.1V Low Cost Application Circuit. Figure 40 : A 5.1V/12V Multiple Supply. Note the Synchronization between the L4972A and L4970A.
PAGE 109
L4972A-L4972AD Figure 41 : L4972A’s Sync. Example. Figure 42: 1A/24V Multiple Supply.
PAGE 110
L4972A-L4972AD POWERDIP20 PACKAGE MECHANICAL DATA mm DIM. MIN. a1 0.51 B 0.85 b b1 TYP. inch MAX. MIN. TYP. MAX. 0.020 1.40 0.033 0.50 0.38 0.020 0.50 D 0.055 0.015 0.020 24.80 0.976 E 8.80 0.346 e 2.54 0.100 e3 22.86 0.900 F 7.10 0.280 I 5.10 0.201 L Z 3.30 0.130 1.27 0.
PAGE 111
L4972A-L4972AD SO20 PACKAGE MECHANICAL DATA mm DIM. MIN. TYP. A a1 inch MAX. TYP. 2.65 0.1 MAX. 0.104 0.3 a2 0.004 0.012 2.45 0.096 b 0.35 0.49 0.014 0.019 b1 0.23 0.32 0.009 0.013 C 0.5 0.020 c1 45 (typ.) D 12.6 13.0 0.496 0.512 E 10 10.65 0.394 0.419 e 1.27 0.050 e3 11.43 0.450 F 7.4 7.6 0.291 0.299 L 0.5 1.27 0.020 0.050 M S 22/23 MIN. 0.75 0.030 8 (max.
PAGE 112
L4972A-L4972AD Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 113
L4974A 3.5A SWITCHING REGULATOR .. .. .. .. . . .. .. 3.5A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE 0 TO 90% DUTY CYCLE RANGE INTERNAL FEED-FORWARD LINE REG. INTERNAL CURRENT LIMITING PRECISE 5.
PAGE 114
L4974A ABSOLUTE MAXIMUM RATINGS Symbol Value Unit V11 Input Voltage Parameter 55 V V11 Input Operating Voltage 50 V V20 Output DC Voltage Output Peak Voltage at t = 0.
PAGE 115
L4974A PIN FUNCTIONS N o Name Fun ction 1 BOOTSTRAP A Cboot capacitor connected between this terminal and the output allows to drive properly the internal D-MOS transistor. 2 RESET DELAY A Cd capacitor connected between this terminal and ground determines the reset signal delay time. 3 RESET OUT Open Collector Reset/power Fail Signal Output. This output is high when the supply and the output voltages are safe. 4 RESET INPUT Input of Power Fail Circuit. The threshold is 5.1V.
PAGE 116
L4974A CIRCUIT OPERATION The L4974A is a 3.5A monolithic stepdown switching regulatorworking in continuousmode realized in the new BCD Technology. This technologyallows the integrationof isolated vertical DMOS power transistors plus mixed CMOS/Bipolar transistors. The device can deliver 3.5A at an output voltage adjustable from 5.1V to 40V and contains diagnostic and control functions that make it particularly suitable for microprocessor based systems.
PAGE 117
L4974A Figure 1 : Feedforward Waveform. Figure 2 : Soft Start Function. Figure 3 : Limiting Current Function.
PAGE 118
L4974A Figure 4 : Reset and Power Fail Functions.
PAGE 119
L4974A ELECTRICAL CHARACTERISTICS (refer to the test circuit, TJ = 25°C, Vi = 35V, R4 = 30KΩ, C9 = 2.7nF, fSW = 100KHz typ, unless otherwise specified) DYNAMIC CHARACTERISTICS Symbol Parameter Vi Input Volt. Range (pin 11) Vo = Vref to 40V Io = 3.5A (*) 15 Max. Un it F ig. 50 V 5 Vo Output Voltage Vi =15V to 50V Io = 2A; V o = Vref 5 5.1 5.2 V 5 ∆Vo Line Regulation VI = 15V to 50V Io = 1A; Vo = Vref 12 30 mV ∆Vo Load Regulation VO = Vref Io = 1A to 3.
PAGE 120
L4974A ELECTRICAL CHARACTERISTICS (continued) DC CHARACTERISTICS Symbol Parameter V11on Turn-on Threshold V11 Hyst Turn-off Hysteresys I11Q Quiescent Current I11OQ I20L Test Cond ition Min. T yp. Max. Unit Fig . 10 11 12 V 7A 1 V 7A V8 = 0; S1 = D 13 19 mA 7A Operating Supply Current V8 = 0; S1 = B; S2 = B 16 23 mA 7A Out Leak Current Vi = 55V; S3 = A; V8 = 0 2 mA 7A Fig .
PAGE 121
L4974A ELECTRICAL CHARACTERISTICS (continued) RESET AND POWER FAIL FUNCTIONS Symbol Min. Typ. Max. Un it F ig. V9R Rising Thereshold Voltage (pin 9) Vi = 15 to 50V V4 = 5.3V Vref -130 Vref -100 Vref -80 V mV 7D V9F Falling Thereshold Voltage (pin 9) Vi = 15 to 50V V4 = 5.3V 4.77 Vref -200 Vref -160 V mV 7D V2H Delay High Threshold Volt. Vi = 15 to 50V V4 = 5.3V V9 = V13 4.95 5.1 5.25 V 7D V2L Delay Low Threshold Volt. Vi = 15 to 50V V4 = 4.7V V9 = V13 1 1.1 1.
PAGE 122
L4974A Figure 6a : Component Layout of fig.5 (1 : 1 scale). Evaluation Board Available PART LIST R1 = 30KΩ R2 = 10KΩ R3 = 15KΩ R4 = 30KΩ R5 = 22Ω R6 = 4.7KΩ R7 = see table A R8 = OPTION R9 = 4.7KΩ * C1 = C2 = 1000µF 63V EYF (ROE) C3 = C4 = C 5 = C 6 = 2,2µF 50V C7 = 390pF Film C8 = 22nF MKT 1837 (ERO) C9 = 2.7nF KP 1830 (ERO) C10 = 0.33µF Film C11 = 1nF ** C12 = C13 = C14 = 100µF 40V EKR (ROE) C15 = 1µF Film D1 = SB 560 (OR EQUIVALENT) L1 = 150µH core 58310 MAGNETICS 45 TURNS 0.
PAGE 123
L4974A Figure 6b: P.C. Board and Component Layout of the Circuit of Fig. 5. (1:1 scale) Figure 7 : DC Test Circuits.
PAGE 124
L4974A Figure 7A. Figure 7B. Figure 7C.
PAGE 125
L4974A Figure 7D. Figure 8 : Quiescent Drain Current vs. Supply Voltage (0% duty cycle - see fig. 7A). Figure 9 : Quiescent Drain Current vs. Junction Temperature (0% duty cycle).
PAGE 126
L4974A Figure 10 : Quiescent Drain Current vs. Duty Cycle. Figure 11 : Reference Voltage (pin 13) vs. Vi (see fig. 7). Figure 12 : Reference Voltage (pin 13) vs. Junction Temperature (see fig. 7). Figure 13 : Reference Voltage (pin 14) vs. Vi (see fig. 7). Figure 14 : Reference Voltage (pin 14) vs. Junction Temperature (see fig. 7). Figure 15 : Reference Voltage 5.1V (pin 13) Supply Voltage Ripple Rejection vs.
PAGE 127
L4974A Figure 16 : Switching Frequency vs. Input Voltage (see fig. 5). Figure 17 : Switching Frequency vs. Junction Temperature (see fig. 5). Figure 18 : Switching Frequency vs. R4 (see fig.5). Figure 19 : Maximum Duty Cycle vs. Frequency. Figure 20 : Supply Voltage Ripple Rejection vs. Frequency (see fig. 5). Figure 21 : Efficiency vs. Output Voltage.
PAGE 128
L4974A Figure 22 : Line Transient Response (see fig. 5). Figure 23 : Load Transient Response (see fig. 5). Figure 24 : Dropout Voltage between Pin 11 and Pin 20 vs. Current at Pin 20. Figure 25 : .Dropout Voltage between Pin 11 and Pin 20 vs. Junction Temperature. Figure 26 : Power Dissipation (device only) vs. Input Voltage. Figure 27 : Power Dissipation (device only) vs. Input Voltage.
PAGE 129
L4974A Figure 28 : Power Dissipation (device only) vs. Output Voltage. Figure 29 : Power Dissipation (device only) vs. Output Voltage. Figure 30 : Power Dissipation (device only) vs. Output Current. Figure 31 : Power Dissipation (device only) vs. Output Current. Figure 32 : Efficiency vs. Output Current. Figure 33 : Test PCB Thermal Characteristic.
PAGE 130
L4974A Figure 34 : Junction to Ambient Thermal Resistance vs. Area on Board Heatsink (DIP 16+2+2) Figure 36: Open Loop Frequency and Phase of Error Amplifier (see fig. 7C). 18/22 Figure 35: Maximum Allowable Power Dissipation vs.
PAGE 131
L4974A Figure 37 : 3.5A – 5.1V Low Cost Application Circuit. Figure 38 : A 5.1V/12V Multiple Supply. Note the Synchronization between the L4974A and L4970A.
PAGE 132
L4974A Figure 39 : L4974A’s Sync. Example. Figure 40: 1A/24V Multiple Supply.
PAGE 133
L4974A POWERDIP20 PACKAGE MECHANICAL DATA mm DIM. MIN. a1 0.51 B 0.85 b b1 TYP. inch MAX. MIN. TYP. MAX. 0.020 1.40 0.033 0.50 0.38 0.020 0.50 D 0.055 0.015 0.020 24.80 0.976 E 8.80 0.346 e 2.54 0.100 e3 22.86 0.900 F 7.10 0.280 I 5.10 0.201 L Z 3.30 0.130 1.27 0.
PAGE 134
L4974A Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 135
L4975A 5A SWITCHING REGULATOR 5A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE 0 TO 90% DUTY CYCLE RANGE INTERNAL FEED-FORWARD LINE REGULATION INTERNAL CURRENT LIMITING PRECISE 5.
PAGE 136
L4975A ABSOLUTE MAXIMUM RATINGS Symbol Value Unit V9 Input Voltage Parameter 55 V V9 Input Operating Voltage 50 V V7 Output DC Voltage Output Peak Voltage at t = 0.
PAGE 137
L4975A PIN FUNCTIONS o N Name Function 1 OSCILLATOR Rosc. External resistor connected to ground determines the constant charging current of C osc. 2 OSCILLATOR Cosc. External capacitor connected to ground determines (with R osc) the switching frequency. 3 RESET INPUT Input of Power Fail Circuit. The threshold is 5.1V. It may be connected via a divider to the input for power fail function. It must be connected to the pin 14 an external 30KΩ resistor when power fail signal not required.
PAGE 138
L4975A Figure 1: Feedforward Waveform Figure 2: Soft Start Function Figure 3: Limiting Current Function 4/21
PAGE 139
L4975A stability of the loop can be adjusted by an external RC network connected to the output of the error amplifier. A voltage feedforward control has been added to the oscillator, this maintains superior line regulation over a wide input voltage range. Closing the loop directly gives an output voltage of 5.1V, higher voltages are obtained by inserting a voltage divider. At turn on output overcurrents are prevented by the soft start function (fig. 2).
PAGE 140
L4975A ELECTRICAL CHARACTERISTICS (Refer to the test circuit, Tj = 25°C, Vi = 35V, R4 = 16KΩ, C9 = 2.2nF, fSW = 200KHz typ, unless otherwise specified) DYNAMIC CHARACTERISTICS Symbol Parameter Test Condition Min. Vi input Voltage Range (pin 9) Vo = Vref to 40V Io = 5A 15 Vo Output Votage Vi = 15V to 50V Io = 3A; Vo = Vref 5 ∆Vo Line Regulation Vi = 15V to 50V Io = 2A; Vo = Vref ∆Vo Load Regulation Vo = Vref Io = 2A to 4A Io = 1A to 5A Typ. Max. Unit Fig. 50 V 5 5.1 5.
PAGE 141
L4975A ELECTRICAL CHARACTERISTICS (continued) DC CHARACTERISTICS Symbol Parameter V9on Turn-on Threshold V9 Hyst Turn-off Hysteresys Test Condition Min. Typ. Max. Unit Fig. 10 11 12 V 7A V 7A I9Q Quiescent Current V12 = 0; S1 = D 13 19 mA 7A I9OQ Operating Supply Current V12 = 0; S1 = C; S2 = B 16 23 mA 7A Out Leak Current Vi = 55V; S3 = A; V12 = 0 2 mA 7A Fig.
PAGE 142
L4975A ELECTRICAL CHARACTERISTICS (continued) RESET AND POWER FAIL FUNCTIONS Symbol Parameter Min. Typ. Max. Unit Fig. V11R Rising Threshold Voltage (pin 11) Vi = 15 to 50V V3 = 5.3V Test Condition Vref –120 Vref –100 Vref –80 V mV 7D V11F Falling Threshold Voltage (pin 11) Vi = 15 to 50V V3 = 5.3V 4.77 Vref –200 Vref –160 V mV 7D V5H Delay High Threshold Voltage Vi = 15 to 50V V11 = V14 4.95 5.1 5.25 V 7D V5L Delay Low Threshold Voltage Vi = 15 to 50V V11 = V14 V3 = 5.
PAGE 143
L4975A Figure 6a: P.C. Board (components side) and Components Layout of Figure 5 (1:1 scale). PARTS LIST Table A R1 = 30KΩ C 1, C2 = 3300µF 63VL EYF (ROE R2 = 10KΩ C 3, C4, C5, C6 = 2.2µF R3 = 15KΩ C 7 = 390pF Film R4 = 16KΩ C 8 = 22nF MKT 1817 (ERO) R5 = 22Ω 0,5W R6 = 4K7 C 9 = 2.2nF KP1830 R7 = 10Ω C 10 = 220nF MKT R8 = see tab. A C 11 = 2.2nF MP1830 R9 = OPTION **C12 , C13, C14 = 220µF 40VL EKR R10 = 4K7 C 15 = 1µF Film V0 R9 R7 12V 15V 18V 24V 4.7kΩ 4.7kΩ 4.7kΩ 4.7kΩ 6.2kW 9.
PAGE 144
L4975A Figure 6b: P.C. Board (Back side) and Components Layout of the Circuit of Fig. 5.
PAGE 145
L4975A Figure 7A Figure 7B 11/21
PAGE 146
L4975A Figure 7D Figure 7C 12/21
PAGE 147
L4975A Figure 8: Quiescent Drain Current vs. Supply Voltage (0% duty cycle - see fig. 7A). Figure 9: Quiescent Drain Current vs. Junction Temperature (0% duty cycle). Figure 10: Quiescent Drain Current vs. Duty Cycle Figure 11: Reference Voltage (pin14) vs. Vi (see fig. 7) Figure 12: Reference Voltage (pin 14) vs. Junction Temperature (see fig. 7) Figure 13: Reference Voltage (pin15) vs. Vi (see fig.
PAGE 148
L4975A Figure 14: Reference Voltage (pin 15) vs. Junction Temperature (see fig. 7) Figure 15: Reference Voltage 5.1V (pin 14) Supply Voltage Ripple Rejection vs. Frequency Figure 16: Switching Frequency vs. Input Voltage (see fig. 5) Figure 17: Switching Frequency vs. Junction Temperature (see fig 5) Figure 18: Switching Frequency vs. R4 (see fig. 5) Figure 19: Max. Duty Cycle vs.
PAGE 149
L4975A Figure 20: Supply Voltage Ripple Rejection vs. Frequency (see fig. 5) Figure 21: Line Transient Response (see fig. 5) Figure 22: Load Transient Response (see fig. 5) Figure 23: Dropout Voltage Between Pin 9 and Pin 7 vs. Current at Pin 7 Figure 24: Dropout Voltage Between Pin 9 and Pin 7 vs. Junction Temperature Figure 25: Power Dissipation (device only) vs.
PAGE 150
L4975A Figure 26: Power Dissipation (device only) vs. Output Voltage Figure 27: Heatsink Used to Derive the Device’s Power Dissipation Tcase − Tamb Rth - Heatsink = Pd Figure 28: Efficiency vs. Output Current Figure 29: Efficiency vs. Output Voltage Figure 30: Efficiency vs. Output Voltage 16/21 Figure 31: Open Loop Frequency and Phase Response of Error Amplifier (see fig.
PAGE 151
L4975A Figure 32: Power Dissipation Derating Curve Figure 33: 5.1V/12V Multiple Supply.
PAGE 152
L4975A Figure 34: 5.1V / 5A Low Cost Application Figure 35: 5A Switching Regulator, Adjustable from 0V to 25V.
PAGE 153
L4975A Figure 36: L4975A’sSync.
PAGE 154
L4975A MULTIWATT15 PACKAGE MECHANICAL DATA DIM. mm MIN. TYP. MIN. TYP. MAX. A 5 0.197 B 2.65 0.104 C 1.6 D 0.063 1 0.039 E 0.49 0.55 0.019 0.022 F 0.66 0.75 0.026 0.030 G 1.14 1.27 1.4 0.045 0.050 0.055 G1 17.57 17.78 17.91 0.692 0.700 0.705 H1 19.6 0.772 H2 20/21 inch MAX. 20.2 0.795 L 22.1 22.6 0.870 0.890 L1 22 22.5 0.866 0.886 L2 17.65 18.1 0.695 0.713 L3 17.25 17.5 17.75 0.679 0.689 0.699 L4 10.3 10.7 10.9 0.406 0.421 0.
PAGE 155
L4975A Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 156
L4977A 7A SWITCHING REGULATOR 7A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE 0 TO 90% DUTY CYCLE RANGE INTERNAL FEED-FORWARD LINE REGULATION INTERNAL CURRENT LIMITING PRECISE 5.
PAGE 157
L4977A ABSOLUTE MAXIMUM RATINGS Symbol Value Unit V9 Input Voltage Parameter 55 V V9 Input Operating Voltage 50 V V7 Output DC Voltage Output Peak Voltage at t = 0.
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L4977A PIN FUNCTIONS o N Name Function 1 OSCILLATOR Rosc. External resistor connected to ground determines the constant charging current of C osc. 2 OSCILLATOR Cosc. External capacitor connected to ground determines (with R osc) the switching frequency. 3 RESET INPUT Input of Power Fail Circuit. The threshold is 5.1V. It may be connected via a divider to the input for power fail function. It must be connected to the pin 14 an external 30KΩ resistor when power fail signal not required.
PAGE 159
L4977A Figure 1: Feedforward Waveform Figure 2: Soft Start Function Figure 3: Limiting Current Function 4/21
PAGE 160
L4977A stability of the loop can be adjusted by an external RC network connected to the output of the error amplifier. A voltage feedforward control has been added to the oscillator, this maintains superior line regulation over a wide input voltage range. Closing the loop directly gives an output voltage of 5.1V, higher voltages are obtained by inserting a voltage divider. At turn on output overcurrents are prevented by the soft start function (fig. 2).
PAGE 161
L4977A ELECTRICAL CHARACTERISTICS (Refer to the test circuit, Tj = 25°C, Vi = 35V, R4 = 16KΩ, C9 = 2.2nF, fSW = 200KHz typ, unless otherwise specified) DYNAMIC CHARACTERISTICS Symbol Parameter Test Condition Min. Vi input Voltage Range (pin 9) Vo = Vref to 40V Io = 7A 15 Vo Output Votage Vi = 15V to 50V Io = 3A; Vo = Vref 5 ∆Vo Line Regulation Vi = 15V to 50V Io = 2A; Vo = Vref ∆Vo Load Regulation Typ. Max. Unit Fig. 50 V 5 5.1 5.
PAGE 162
L4977A ELECTRICAL CHARACTERISTICS (continued) DC CHARACTERISTICS Symbol Parameter V9on Turn-on Threshold V9 Hyst Turn-off Hysteresys Test Condition Min. Typ. Max. Unit Fig. 10 11 12 V 7A V 7A I9Q Quiescent Current V12 = 0; S1 = D 13 19 mA 7A I9OQ Operating Supply Current V12 = 0; S1 = C; S2 = B 16 23 mA 7A Out Leak Current Vi = 55V; S3 = A; V12 = 0 2 mA 7A Fig.
PAGE 163
L4977A ELECTRICAL CHARACTERISTICS (continued) RESET AND POWER FAIL FUNCTIONS Symbol Parameter Min. Typ. Max. Unit Fig. V11R Rising Threshold Voltage (pin 11) Vi = 15 to 50V V3 = 5.3V Test Condition Vref –120 Vref –100 Vref –80 V mV 7D V11F Falling Threshold Voltage (pin 11) Vi = 15 to 50V V3 = 5.3V 4.77 Vref –200 Vref –160 V mV 7D V5H Delay High Threshold Voltage Vi = 15 to 50V V11 = V14 V3 = 5.3V 4.95 5.1 5.
PAGE 164
L4977A Figure 6a: P.C. Board (components side) and Components Layout of Figure 5 (1:1 scale). PARTS LIST Table A R1 = 30KΩ C 1, C2 = 3300µF 63VL EYF (ROE R2 = 10KΩ C 3, C4, C5, C6 = 2.2µF R3 = 15KΩ C 7 = 390pF Film R4 = 16KΩ C 8 = 22nF MKT 1817 (ERO) R5 = 22Ω 0,5W R6 = 4K7 C 9 = 2.2nF KP1830 R7 = 10Ω C 10 = 220nF MKT R8 = see tab. A C 11 = 2.2nF MP1830 R9 = OPTION **C12 , C13, C14 = 220µF 40VL EKR R10 = 4K7 C 15 = 1µF Film V0 R9 R7 12V 15V 18V 24V 4.7kΩ 4.7kΩ 4.7kΩ 4.7kΩ 6.2kW 9.
PAGE 165
L4977A Figure 6b: P.C. Board (Back side) and Components Layout of the Circuit of Fig. 5.
PAGE 166
L4977A Figure 7A Figure 7B 11/21
PAGE 167
L4977A Figure 7D Figure 7C 12/21
PAGE 168
L4977A Figure 8: Quiescent Drain Current vs. Supply Voltage (0% duty cycle - see fig. 7A). Figure 9: Quiescent Drain Current vs. Junction Temperature (0% duty cycle). Figure 10: Quiescent Drain Current vs. Duty Cycle Figure 11: Reference Voltage (pin14) vs. Vi (see fig. 7) Figure 12: Reference Voltage (pin 14) vs. Junction Temperature (see fig. 7) Figure 13: Reference Voltage (pin15) vs. Vi (see fig.
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L4977A Figure 14: Reference Voltage (pin 15) vs. Junction Temperature (see fig. 7) Figure 15: Reference Voltage 5.1V (pin 14) Supply Voltage Ripple Rejection vs. Frequency Figure 16: Switching Frequency vs. Input Voltage (see fig. 5) Figure 17: Switching Frequency vs. Junction Temperature (see fig 5) Figure 18: Switching Frequency vs. R4 (see fig. 5) Figure 19: Max. Duty Cycle vs.
PAGE 170
L4977A Figure 20: Supply Voltage Ripple Rejection vs. Frequency (see fig. 5) Figure 21: Line Transient Response (see fig. 5) Figure 22: Load Transient Response (see fig. 5) Figure 23: Dropout Voltage Between Pin 9 and Pin 7 vs. Current at Pin 7 Figure 24: Dropout Voltage Between Pin 9 and Pin 7 vs. Junction Temperature Figure 25: Power Dissipation (device only) vs.
PAGE 171
L4977A Figure 26: Power Dissipation (device only) vs. Output Voltage Figure 27: Heatsink Used to Derive the Device’s Power Dissipation Tcase − Tamb Rth - Heatsink = Pd Figure 28: Efficiency vs. Output Current Figure 29: Efficiency vs. Output Voltage Figure 30: Efficiency vs. Output Voltage 16/21 Figure 31: Open Loop Frequency and Phase Response of Error Amplifier (see fig.
PAGE 172
L4977A Figure 32: Power Dissipation Derating Curve Figure 33: A5.1V/12V Multiple Supply.
PAGE 173
L4977A Figure 34: 5.1V / 7A Low Cost Application Figure 35: 7A Switching Regulator, Adjustable from 0V to 25V.
PAGE 174
L4977A Figure 36: L4977A’sSync.
PAGE 175
L4977A MULTIWATT15 PACKAGE MECHANICAL DATA DIM. mm MIN. TYP. MIN. TYP. MAX. A 5 0.197 B 2.65 0.104 C 1.6 D 0.063 1 E 0.49 0.039 0.55 0.019 0.022 F 0.66 0.75 0.026 G 1.14 1.27 1.4 0.045 0.050 0.055 G1 17.57 17.78 17.91 0.692 0.700 0.705 H1 19.6 0.030 0.772 H2 20/21 inch MAX. 20.2 0.795 L 22.1 22.6 0.870 0.890 L1 22 22.5 0.866 0.886 L2 17.65 18.1 0.695 0.713 L3 17.25 17.5 17.75 0.679 0.689 0.699 L4 10.3 10.7 10.9 0.406 0.421 0.
PAGE 176
L4977A Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 177
SG2525A/2527A SG3525A/3527A REGULATING PULSE WIDTH MODULATORS .. .. .. .. . . 8 TO 35 V OPERATION 5.
PAGE 178
SG2525A/27A-SG3525A/27A ABSOLUTE MAXIMUM RATINGS Symbol Value Unit Vi Supply Voltage 40 V VC Collector Supply Voltage 40 V Oscillator Charging Current 5 mA IOSC Parameter Io Output Current, Source or Sink 500 mA IR Reference Output Current 50 mA IT Current through CT Terminal Logic Inputs Analog Inputs 5 – 0.3 to + 5.5 – 0.
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SG2525A/27A-SG3525A/27A ELECTRICAL CHARACTERISTICS (V# i = 20 V, and over operating temperature, unless otherwise specified) Symbol Parameter SG2525A SG2527A Test Conditions SG3525A SG3527A Unit Min. Typ. Max. Min. Typ. Max. 5.05 5.1 5.15 5 5.1 5.2 V 10 20 10 20 mV REFERENCE SECTION VREF Output Voltage Tj = 25 °C ∆VREF Line Regulation Vi = 8 to 35 V ∆VREF Load Regulation ∆VREF/∆T* Temp.
PAGE 180
SG2525A/27A-SG3525A/27A ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter SG2525A SG2527A Test Conditions Min. Typ. 45 49 SG3525A SG3527A Max. Min. Typ. 45 49 Unit Max. PWM COMPARATOR Minimum Duty-cycle 0 Maximum Duty-cycle • Input Threshold Zero Duty-cycle 0.7 Maximum Duty-cycle * Input Bias Current 0.9 0 0.7 % % 0.9 V 3.3 3.6 3.3 3.6 V 0.05 1 0.05 1 µA SHUTDOWN SECTION 50 80 µA 0.4 0.7 V 0.8 1 V 1 0.4 1 mA 0.2 0.5 0.2 0.5 µs Isink = 20 mA 0.
PAGE 181
SG2525A/27A-SG3525A/27A TEST CIRCUIT 5/12
PAGE 182
SG2525A/27A-SG3525A/27A RECOMMENDED OPERATING CONDITIONS (•) Parameter Value Input Voltage (Vi) 8 to 35 V Collector Supply Voltage (VC) 4.5 to 35 V Sink/Source Load Current (steady state) 0 to 100 mA Sink/Source Load Current (peak) 0 to 400 mA Reference Load Current 0 to 20 mA Oscillator Frequency Range 100 Hz to 400 KHz Oscillator Timing Resistor • 2 KΩ to 150 KΩ Oscillator Timing Capacitor 0.001 µF to 0.
PAGE 183
SG2525A/27A-SG3525A/27A Figure 5 : SG1525A Error Amplifier. PRINCIPLES OF OPERATION SHUTDOWN OPTIONS (see Block Diagram) Since both the compensation and soft-start terminals (Pins 9 and 8) have current source pull-ups, either can readily accept a pull-down signal which only has to sink a maximum of 100 µA to turn off the outputs. This is subject to the added requirement of discharging whatever external capacitance may be attached to these pins.
PAGE 184
SG2525A/27A-SG3525A/27A Figure 6 : SG1525A Oscillator Schematic. Figure 7 : SG1525A Output Circuit (1/2 circuit shown).
PAGE 185
SG2525A/27A-SG3525A/27A Figure 8. Figure 9. For single-ended supplies, the driver outputs are grounded. The VC terminal is switched to ground by the totem-pole source transistors on alternate oscillator cycles. In conventional push-pull bipolar designs, forward base drive is controlled by R1 - R3. Rapid turn-off times for the power devices are achieved with speed-up capacitors C1 and C2. Figure 10. Figure 11.
PAGE 186
SG2525A/27A-SG3525A/27A DIP16 PACKAGE MECHANICAL DATA mm DIM. MIN. a1 0.51 B 0.77 TYP. MAX. MIN. TYP. MAX. 0.020 1.65 0.030 0.065 b 0.5 0.020 b1 0.25 0.010 D 20 0.787 E 8.5 0.335 e 2.54 0.100 e3 17.78 0.700 F 7.1 0.280 I 5.1 0.201 L Z 10/12 inch 3.3 0.130 1.27 0.
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SG2525A/27A-SG3525A/27A SO16 NARROW PACKAGE MECHANICAL DATA mm DIM. MIN. TYP. A a1 inch MAX. MIN. TYP. 1.75 0.1 0.069 0.25 a2 MAX. 0.004 0.009 1.6 0.063 b 0.35 0.46 0.014 0.018 b1 0.19 0.25 0.007 0.010 C 0.5 0.020 c1 45° (typ.) D 9.8 10 0.386 0.394 E 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 8.89 0.350 F 3.8 4.0 0.150 0.157 L 0.4 1.27 0.150 0.050 M S 0.62 0.024 8° (max.
PAGE 188
SG2525A/27A-SG3525A/27A Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
PAGE 189
UC2842/3/4/5 UC3842/3/4/5 CURRENT MODE PWM CONTROLLER . .. .. . .. . ..
PAGE 190
UC2842/3/4/5-UC3842/3/4/5 ABSOLUTE MAXIMUM RATINGS Symbo l Parameter Vi Supply Voltage (low impedance source) Valu e Unit 30 V Vi Supply Voltage (Ii < 30mA) IO Output Current Self Limiting ±1 A EO Output Energy (capacitive load) 5 µJ Analog Inputs (pins 2, 3) – 0.3 to 6.
PAGE 191
UC2842/3/4/5-UC3842/3/4/5 ELECTRICAL CHARACTERISTICS (Unless otherwise stated, these specifications apply for -25 < Tamb < 85°C for UC2824X; 0 < Tamb < 70°C for UC384X; Vi = 15V (note 5); RT = 10K; CT = 3.3nF) Test Co nditions UC284X UC384X Min. Typ. Max. Min . T yp. Max. Unit 4.95 5.00 5.05 4.90 5.00 5.
PAGE 192
UC2842/3/4/5-UC3842/3/4/5 ELECTRICAL CHARACTERISTICS (continued) Symbo l Parameter Test Co nditi ons UC284X UC384X Min. Typ . Max. Min . Typ. Max. Unit UNDER-VOLTAGE LOCKOUT SECTION Start Threshold Min Operating Voltage After Turn-on X842/4 15 16 17 14.5 16 17.5 V X843/5 7.8 8.4 9.0 7.8 8.4 9 V X842/4 9 10 11 8.5 10 11.5 V X843/5 7.0 7.6 8.2 7.0 7.6 8.
PAGE 193
UC2842/3/4/5-UC3842/3/4/5 Figure 1 : Error Amp Configuration. Error amp can source or sink up to 0.5mA Figure 2 : Under Voltage Lockout. During Under-Voltage Lockout, the output driver is biased to sink minor amounts of current. Pin 6 should be shunted to ground with a bleeder resistor to prevent activating the power switch with extraneous leakage currents. Figure 3 : Current Sense Circuit . Peak current (is) is determined by the formula 1.
PAGE 194
UC2842/3/4/5-UC3842/3/4/5 Figure 4. Figure 5 : Deadtime vs. CT (RT > 5KΩ). for RT > 5KΩ f = 1.72 RTCT Figure 6 : Timing Resistance vs. Frequency. Figure 8 : Error Amplifier Open-loop Frequency Response. 6/11 Figure 7 : Output Saturation Characteristics.
PAGE 195
UC2842/3/4/5-UC3842/3/4/5 Figure 9 : Open Loop Test Circuit. High peak currents associated with capacitive loads necessitate careful grounding techniques. Timing and bypass capacitors should be connected close to pin 5 in a single point ground. The transistor and 5 KΩ potentiometerare used to sample the oscillator waveform and apply an adjustable ramp to pin 3. Figure 10 : Shutdown Techniques.
PAGE 196
UC2842/3/4/5-UC3842/3/4/5 Figure 11 : Off-line Flyback Regulator. Power Supply Specifications 1. Input Voltage : 95 VAC to 130 VAC (50 Hz/60 Hz) 2. Line Isolation : 3750 V 3. Switching Frequency : 40 KHz 4. Efficiency @ Full Load : 70 % 5. Output Voltage : A. + 5 V, ± 5 % : 1 A to 4 A load Ripple voltage : 50 mV P-P Max. B. + 12 V, ± 3 % : 0.1 A to 0.3 A load Ripple voltage : 100 mV P-P Max. C. – 12 V, ± 3 % : 0.1 A to 0.3 A load Ripple voltage : 100 mV P-P Max. Figure 12 : Slope Compensation.
PAGE 197
UC2842/3/4/5-UC3842/3/4/5 SO14 PACKAGE MECHANICAL DATA mm DIM. MIN. TYP. A a1 inch MAX. MIN. TYP. 1.75 0.1 0.069 0.25 a2 MAX. 0.004 0.009 1.6 0.063 b 0.35 0.46 0.014 0.018 b1 0.19 0.25 0.007 0.010 C 0.5 0.020 c1 45 (typ.) D 8.55 8.75 0.336 0.344 E 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 7.62 0.300 F 3.8 4.0 0.15 0.157 L 0.4 1.27 0.016 0.050 M S 0.68 0.027 8 (max.
PAGE 198
UC2842/3/4/5-UC3842/3/4/5 DIP14 PACKAGE MECHANICAL DATA mm DIM. MIN. A TYP. MAX. MIN. 3.32 TYP. MAX. 0.131 a1 0.51 0.020 B 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 0.012 D E 10.92 7.95 9.75 0.430 0.313 0.384 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 6.6 0.260 I 5.08 0.200 L 10/11 inch 3.18 3.81 0.125 0.
PAGE 199
UC2842/3/4/5-UC3842/3/4/5 Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.