Datasheet

ManualsBrandsLinear Technology ManualsDC / DC Adjustable Switching RegulatorsSwitching Regulator IC Step-Down LGA- 5.5V

LTM4622

Rev. G

For more information www.analog.com

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TYPICAL APPLICATION

FEATURES DESCRIPTION

Dual Ultrathin 2.5A or Single 5A

Step-Down DC/DC µModule Regulator

The LT M

4622 is a complete dual 2.5A step-down switch-

ing mode µModule

(powermodule) regulator in a tiny

ultrathin 6.25mm × 6.25mm × 1.82mm LGA and 6.25mm

× 6.25mm × 2.42mm BGA packages. Included in the pack-

age are the switching controller, power FETs, inductor and

support components. Operating over an input voltage

range of 3.6V to 20V, the LTM4622 supports an output

voltage range of 0.6V to 5.5V, set by a single external

resistor. Its high efficiency design delivers dual 2.5A con-

tinuous, 3A peak, output current. Only a few ceramic input

and output capacitors are needed.

The LTM4622 supports selectable Burst Mode operation

and output voltage tracking for supply rail sequencing.

Its high switching frequency and current mode control

enable a very fast transient response to line and load

changes without sacrificing stability.

Fault protection features include input overvoltage, output

overcurrent and overtemperature protection.

The LTM4622 is available with SnPb (BGA) or RoHS com-

pliant terminal finish.

1.5V and 1V Dual Output DC/DC Step-Down µModule Regulator 1.5V Output Efficiency vs Load Current

APPLICATIONS

Complete Solution in <1cm

Wide Input Voltage Range: 3.6V to 20V

3.3V Input Compatible with V

Tied to INTV

0.6V to 5.5V Output Voltage

Dual 2.5A (3A Peak) or Single 5A Output Current

±1.5% Maximum Total Output Voltage Regulation

Error Over Load, Line and Temperature

Current Mode Control, Fast Transient Response

External Frequency Synchronization

Multiphase Parallelable with Current Sharing

Output Voltage Tracking and Soft-Start Capability

Selectable Burst Mode

Operation

Overvoltage Input and Overtemperature Protection

Power Good Indicators

6.25mm × 6.25mm × 1.82mm LGA and 6.25mm ×

6.25mm × 2.42mm BGA Packages

General Purpose Point-of-Load Conversion

Telecom, Networking and Industrial Equipment

Medical Diagnostic Equipment

Test and Debug Systems

LOAD CURRENT (A)

EFFICIENCY (%)

4622 TA01b

0.5 1.0 1.5 2.0

2.5

= 5V

= 12V

Document Feedback

90.9k

4622 TA01a

4.7µF

25V

3.6V TO 20V

OUT1

1V, 2.5A

47µF

OUT1

OUT2

1.5V, 2.5A

47µF

OUT2

FB1

COMP1

COMP2

GND

LTM4622

PGOOD1 PGOOD2

IN2

IN1

RUN1

RUN2

INTV

SYNC/MODE

TRACK/SS1

TRACK/SS2

FREQ

40.2k

FB2

Downloaded from Arrow.com.

Summary of content (28 pages)

PAGE 1
LTM4622 Dual Ultrathin 2.5A or Single 5A Step-Down DC/DC µModule Regulator FEATURES DESCRIPTION Complete Solution in <1cm2 nn Wide Input Voltage Range: 3.6V to 20V nn 3.3V Input Compatible with V Tied to INTV IN CC nn 0.6V to 5.5V Output Voltage nn Dual 2.5A (3A Peak) or Single 5A Output Current nn ±1.
PAGE 2
LTM4622 ABSOLUTE MAXIMUM RATINGS (Note 1) VIN1, VIN2.................................................... –0.3V to 22V VOUT.............................................................. –0.3V to 6V PGOOD1, PGOOD2...................................... –0.3V to 18V RUN1, RUN2..................................... –0.3V to VIN + 0.3V INTVCC, TRACK/SS1, TRACK/SS2............. –0.3V to 3.6V SYNC/MODE, COMP1, COMP2, FB1, FB2................................................ –0.
PAGE 3
LTM4622 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full internal operating temperature range (Note 2). Specified as each individual output channel at TA = 25°C, VIN1 = VIN2 = 12V, unless otherwise noted per the typical application shown in Figure 24. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Switching Regulator Section: per Channel VIN1 Input DC Voltage l 3.6 VIN2 Input DC Voltage VIN_3.3 3.3V Input DC Voltage VOUT(RANGE) 20 V 3.
PAGE 4
LTM4622 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full internal operating temperature range (Note 2). Specified as each individual output channel at TA = 25°C, VIN1 = VIN2 = 12V, unless otherwise noted per the typical application shown in Figure 24. SYMBOL PARAMETER CONDITIONS RPGOOD PGOOD Pull-Down Resistance 1mA Load VINTVCC Internal VCC Voltage VIN1 = VIN2 = 3.6V to 20V VINTVCC Load Reg INTVCC Load Regulation ICC = 0mA to 50mA 1.
PAGE 5
LTM4622 TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Load Current at 12VIN Efficiency vs Load Current at 3.3VIN 95 95 90 90 90 85 85 85 80 75 70 OUTPUT: 3.3V, 2MHz 1.8V, 1MHz 1.2V, 1MHz 65 60 0 0.5 EFFICIENCY (%) 95 EFFICIENCY (%) EFFICIENCY (%) Efficiency vs Load Current at 5VIN 80 75 OUTPUT: 5.0V, 2.5MHz 2.5V, 1.5MHz 1.5V, 1MHz 1.0V, 1MHz 70 2.5V, 1.5MHz 1.5V, 1MHz 1.0V, 1MHz 1.0 1.5 2.0 LOAD CURRENT (A) 2.5 65 3 60 0 0.5 4622 G01 Burst Mode Efficiency, 12VIN, 1.5VOUT 1.
PAGE 6
LTM4622 TYPICAL PERFORMANCE CHARACTERISTICS Start-Up with No Load Current Applied 5V Output Transient Response 3.3V Output Transient Response SW 10V/DIV VOUT 100mV/DIV AC-COUPLED VOUT 100mV/DIV AC-COUPLED VOUT 1V/DIV LOAD STEP 1A/DIV LOAD STEP 1A/DIV 4622 G10 VIN = 12V 20µs/DIV VOUT = 5V FS = 2.5MHz OUTPUT CAPACITOR = 1 × 47µF CERAMIC LOAD STEP = 1.25A TO 2.5A 4622 G09 20µs/DIV VIN = 12V VOUT = 3.3V FS = 2MHz OUTPUT CAPACITOR = 1 × 47µF CERAMIC LOAD STEP = 1.25A TO 2.
PAGE 7
LTM4622 PIN FUNCTIONS PACKAGE ROW AND COLUMN LABELING MAY VARY AMONG µModule PRODUCTS. REVIEW EACH PACKAGE LAYOUT CAREFULLY. VIN1 (D3, E2), VIN2 (A2, B3): Power Input Pins. Apply input voltage between these pins and GND pins. Recommend placing input decoupling capacitance directly between BOTH VIN1 and VIN2 pins and GND pins. Please note the module internal control circuity is running off VIN1. Channel 2 will not work without a voltage higher that 3.6V present at VIN1.
PAGE 8
LTM4622 BLOCK DIAGRAM VOUT1 VOUT2 60.4k FB1 60.4k 60.4k FB2 40.2k INTVCC PGOOD1 10k PGOOD2 10k INTVCC INTVCC VIN1 2.2µF 0.22µF 22µF SYNC/MODE TRACK/SS1 1µH VOUT1 1.2V 2.5A VOUT1 0.1µF 1µF TRACK/SS2 VIN 3.6V TO 20V 47µF GND 0.1µF RUN1 RUN2 VIN2 COMP1 0.22µF POWER CONTROL INTERNAL COMP 1µH 10µF VOUT2 1.5V 2.5A VOUT2 1µF COMP2 47µF GND INTERNAL COMP FREQ 324k 4622 BD Figure 1.
PAGE 9
LTM4622 OPERATION The LTM4622 is a dual output standalone non-isolated switch mode DC/DC power supply. It can deliver two 2.5A DC, 3A peak output current with few external input and output ceramic capacitors. This module provides dual precisely regulated output voltage programmable via two external resistor from 0.6V to 5.5V over 3.6V to 20V input voltage range. With INTVCC tied to VIN, this module is able to operate from 3.3V input. The typical application schematic is shown in Figure 24.
PAGE 10
LTM4622 APPLICATIONS INFORMATION Output Voltage Programming Output Decoupling Capacitors The PWM controller has an internal 0.6V reference voltage. As shown in the Block Diagram, a 60.4k 0.5% internal feedback resistor connects VOUT and FB pins together.
PAGE 11
LTM4622 APPLICATIONS INFORMATION always turns on with each oscillator pulse. During startup, forced continuous mode is disabled and inductor current is prevented from reversing until the LTM4622’s output voltage is in regulation. Operating Frequency The operating frequency of the LTM4622 is optimized to achieve the compact package size and the minimum out-put ripple voltage while still keeping high efficiency. The default operating frequency is internally set to 1MHz.
PAGE 12
LTM4622 APPLICATIONS INFORMATION The LTM4622 device is an inherently current mode controlled device, so parallel modules will have very good current sharing. This will balance the thermals on the design. Please tie RUN, TRACK/SS, FB and COMP pin of each paralleling channel together. Figure 28 shows an example of parallel operation and pin connection. INPUT RMS Ripple Current Cancellation Application Note 77 provides a detailed explanation of multiphase operation.
PAGE 13
LTM4622 APPLICATIONS INFORMATION tracked up and down with another regulator. Figure 4 and Figure 5 show an example waveform and schematic of a Ratiometric tracking where the slave regulator’s output slew rate is proportional to the master’s. Since the slave regulator’s TRACK/SS is connected to the master’s output through a RTR(TOP)/RTR(BOT) resistor The RFB(SL) is the feedback resistor and the RTR(TOP)/ RTR(BOT) is the resistor divider on the TRACK/SS pin of the slave regulator, as shown in Figure 5.
PAGE 14
LTM4622 APPLICATIONS INFORMATION From the equation, we could easily find out that, in the Coincident tracking, the slave regulator’s TRACK/SS pin resistor divider is always the same as its feedback divider. R FB(SL) R FB(SL) + 60.4k = R TR(BOT) R TR(TOP) + R TR(BOT) For example, RTR(TOP) = 60.4k and RTR(BOT) = 60.4k is a good combination for Coincident tracking for VOUT(MA) = 1.5V and VOUT(SL) = 1.2V application.
PAGE 15
LTM4622 APPLICATIONS INFORMATION JUNCTION-TO-AMBIENT THERMAL RESISTANCE COMPONENTS CASE (TOP)-TO-AMBIENT RESISTANCE JUNCTION-TO-CASE (TOP) RESISTANCE JUNCTION JUNCTION-TO-BOARD RESISTANCE AMBIENT JUNCTION-TO-CASE CASE (BOTTOM)-TO-BOARD (BOTTOM) RESISTANCE RESISTANCE BOARD-TO-AMBIENT RESISTANCE 4622 F07 µMODULE DEVICE Figure 7. Graphical Representation of JESD 51-12 Thermal Coefficients board—also defined by JESD51-9 (Test Boards for Area Array Surface Mount Package Thermal Measurements).
PAGE 16
LTM4622 APPLICATIONS INFORMATION A graphical representation of the aforementioned thermal resistances is given in Figure 7; blue resistances are contained within the μModule regulator, whereas green resistances are external to the µModule. As a practical matter, it should be clear to the reader that no individual or sub-group of the four thermal resistance parameters defined by JESD 51-12 or provided in the Pin Configuration section replicates or conveys normal operating conditions of a μModule.
PAGE 17
LTM4622 APPLICATIONS INFORMATION 2.5 1.0 1.5 1.0 0.5 0 1.5 1.0 0 1 4 3 2 OUTPUT CURRENT (A) 0 5 4 3 2 0 1 4622 F11 4 3 2 OUTPUT CURRENT (A) 0 5 Figure 12. 5V Output Power Loss 5 5 0LFM 200LFM 400LFM 1 0 40 50 OUTPUT CURRENT (A) 5 4 3 2 0LFM 200LFM 400LFM 1 0 60 70 80 90 100 110 120 AMBIENT TEMPERATURE (˚C) 40 50 4622 F14 4 3 2 0 60 70 80 90 100 110 120 AMBIENT TEMPERATURE (˚C) Figure 15. 5V to 1.
PAGE 18
LTM4622 6 6 5 5 OUTPUT CURRENT (A) OUTPUT CURRENT (A) APPLICATIONS INFORMATION 4 3 2 0LFM 200LFM 400LFM 1 0 40 50 4 3 2 0LFM 200LFM 400LFM 1 0 60 70 80 90 100 110 120 AMBIENT TEMPERATURE (˚C) 4622 F20 40 50 60 70 80 90 100 110 120 AMBIENT TEMPERATURE (˚C) 4622 F21 Figure 20. 12V to 3.3V Derating Curve, No Heat Sink Figure 21. 12V to 5V Derating Curve, No Heat Sink Table 2.
PAGE 19
LTM4622 APPLICATIONS INFORMATION Table 7. Output Voltage Response for Each Regulator Channel vs Component Matrix (Refer to Figure 24) 1.25A Load Step Typical Measured Values CIN (CERAMIC) PART NUMBER COUT1 (CERAMIC) PART NUMBER VALUE COUT2 (BULK) VALUE Murata GRM188R61E475KE11# 4.7µF, 25V, Murata 0603, X5R GRM21R60J476ME15# Murata GRM188R61E106MA73# 10µF, 25V, Murata 0603, X5R GRM188R60J226MEA0# 22µF, 6.3V, 0603, X5R Taiyo Yuden TMK212BJ475KG-T VOUT (V) 4.
PAGE 20
LTM4622 APPLICATIONS INFORMATION flows from the junction through the board into ambient with no airflow or top mounted heat sink. The 1V, 1.5V, 2.5V, 3.3V and 5V power loss curves in Figures 8 to 12 can be used in coordination with the load current derating curves in Figures 13 to 21 for calculating an approximate θJA thermal resistance for the LTM4622 (in two-phase single output operation) with no heat sinking and various airflow conditions.
PAGE 21
LTM4622 APPLICATIONS INFORMATION SAFETY CONSIDERATIONS The LTM4622 modules do not provide galvanic isolation from VIN to VOUT. There is no internal fuse. If required, a slow blow fuse with a rating twice the maximum input current needs to be provided to protect each unit from catastrophic failure. The device does support thermal shutdown and over current protection. LAYOUT CHECKLIST/EXAMPLE The high integration of LTM4622 makes the PCB board layout very simple and easy.
PAGE 22
LTM4622 APPLICATIONS INFORMATION PGOOD1 PGOOD2 VIN 4V TO 20V 10µF VIN2 10µF LTM4622 RUN1 VOUT2 RUN2 0.1µF 0.1µF VOUT1 1V, 2.5A VOUT1 VIN1 INTVCC COMP1 SYNC/MODE COMP2 TRACK/SS1 FB1 TRACK/SS2 FB2 FREQ 10µF 90.6k 30.1k GND VOUT2 1.8V, 2.5A 4622 F24 Figure 24. 4VIN to 20VIN, 1V and 1.8V Output at 2.5A Design PGOOD PGOOD1 PGOOD2 VOUT1 VIN1 VIN 4V TO 20V VIN2 10µF LTM4622 RUN1 RUN2 VOUT2 COMP1 INTVCC SYNC/MODE 0.1µF VOUT 1.
PAGE 23
LTM4622 APPLICATIONS INFORMATION PGOOD1 PGOOD2 VOUT1 VIN1 VIN 3.3V VIN2 10µF RUN1 10µF LTM4622 VOUT2 RUN2 VOUT1 60.4k INTVCC COMP1 SYNC/MODE COMP2 TRACK/SS1 FB1 TRACK/SS2 FB2 FREQ 0.1µF VOUT1 1.5V, 2.5A 10µF 40.2k 60.4k GND VOUT2 1.2V, 2.5A 4622 F27 60.4k Figure 27. 3.3VIN, 1.5V and 1.2V Output at 2.
PAGE 24
LTM4622 PACKAGE DESCRIPTION PACKAGE ROW AND COLUMN LABELING MAY VARY AMONG µModule PRODUCTS. REVIEW EACH PACKAGE LAYOUT CAREFULLY.
PAGE 25
0.000 For more information www.analog.com 2.540 1.270 0.3175 0.3175 1.270 2.540 PACKAGE TOP VIEW SUGGESTED PCB LAYOUT TOP VIEW 2.540 4 1.270 PIN “A1” CORNER E 1.270 aaa Z 0.3175 0.000 0.3175 Y D X aaa Z // bbb Z SYMBOL A b D E e F G H1 H2 aaa bbb eee 0.27 1.45 MIN 1.72 0.60 NOM 1.82 0.63 6.25 6.25 1.27 5.08 5.08 0.32 1.50 DIMENSIONS Ø eee S Z X Y H1 SUBSTRATE 0.37 1.55 0.15 0.10 0.15 MAX 1.92 0.
PAGE 26
0.000 For more information www.analog.com 2.540 1.270 0.3175 0.3175 1.270 2.540 SUGGESTED PCB LAYOUT TOP VIEW 2.540 PACKAGE TOP VIEW 1.270 4 0.3175 0.000 0.3175 PIN “A1” CORNER E 1.270 aaa Z 2.540 Downloaded from Arrow.com. D X 0.630 ±0.025 Y // bbb Z DETAIL B H2 b1 NOM 2.42 0.60 1.82 0.75 0.63 6.25 6.25 1.27 5.08 5.08 0.32 1.50 MAX 2.62 0.70 1.92 0.90 0.
PAGE 27
LTM4622 REVISION HISTORY REV DATE DESCRIPTION A 08/15 Added “Single 5A” to Title and Features PAGE NUMBER B 01/16 Added BGA package C 11/16 Corrected equations of tracking start-up time from RTR(TOP)/[RTR(TOP) + RTR(BOT)] to RTR(BOT)/[RTR(TOP) + RTR(BOT)] D 05/17 Changed MSL Rating from 3 to 4 2 E 01/18 Removed unnecessary sentence from Pre-Biased Output Start-Up section 14 F 03/18 Corrected RFSET to GND G 09/18 Split common VIN into VIN1 and VIN2 1 1, 2, 25, 26 13, 14 9, 11 1, 2
PAGE 28
LTM4622 PACKAGE PHOTO DESIGN RESOURCES SUBJECT DESCRIPTION µModule Design and Manufacturing Resources Design: • Selector Guides • Demo Boards and Gerber Files • Free Simulation Tools µModule Regulator Products Search 1. Sort table of products by parameters and download the result as a spread sheet. Manufacturing: • Quick Start Guide • PCB Design, Assembly and Manufacturing Guidelines • Package and Board Level Reliability 2. Search using the Quick Power Search parametric table.