IFX91041 1.8A DC/DC Step-Down Voltage Regulator 5.0V, 3.3V or Adjustable Output Voltage IFX91041EJV50 IFX91041EJV33 IFX91041EJV Data Sheet Rev. 1.
1.8A DC/DC Step-Down Voltage Regulator 1 • • • • • • • • • • • • • IFX91041 Overview 1.8A step down voltage regulator Output voltage versions: 5.0 V, 3.3 V and adjustable ± 2% output voltage tolerance (+-4% for full load current range) Integrated power transistor PWM regulation with feedforward Input voltage range from 4.
IFX91041 Block Diagram 2 Block Diagram 7 EN 8 VS Enable Charge Pump Over Temperature Shutdown 5 BDS Feedforward COMP SYNC 3 1 Buck Converter 6 BUO Oscillator 4 Bandgap Reference FB Soft start ramp generator IFX91041 2 Figure 1 Data Sheet GND Block Diagram 3 Rev. 1.
IFX91041 Pin Configuration 3 Pin Configuration 3.1 Pin Assignment SYNC 1 GND IFX91041 8 VS 2 7 EN COMP 3 6 BUO FB 4 5 BDS S08_PIN.vsd Figure 2 Pin Configuration 3.2 Pin Definitions and Functions Pin Symbol Function 1 SYNC Synchronization Input. Connect to an external clock signal in order to synchronize/adjust the switching frequency. If not used connect to GND. 2 GND Ground. 3 COMP Compensation Input. Frequency compensation for regulation loop stability.
IFX91041 General Product Characteristics 4 General Product Characteristics 4.1 Absolute Maximum Ratings Absolute Maximum Ratings1) Tj = -40 °C to +125°C; all voltages with respect to ground (unless otherwise specified) Pos. Parameter Symbol Limit Values Unit Conditions Min. Max. -0.3 5.5 V – 6.2 V t < 10s2) 5.5 V – 6.2 V t < 10s1) -0.3 10 V IFX91041EJV50; IFX91041EJV33 -0.3 5.5 V IFX91041EJV VBUO VBUO V - 0.3 + 5.5 VBUO VEN VVS -2.0 VVS + 0.3 V -40 45 V -0.
IFX91041 General Product Characteristics 4.2 Functional Range Pos. Parameter Symbol 4.2.1 Supply Voltage 4.2.2 Output Voltage adjust range 4.2.3 Buck inductor 4.2.4 Buck capacitor 4.2.5 Buck capacitor ESR 4.2.6 Junction Temperature VS VCC LBU CBU1 ESRBU1 Tj Limit Values Unit Conditions Min. Max. 4.75 45 V – 0.60 16 V IFX91041EJV 18 56 µH – 33 120 µF – – 0.
IFX91041 Buck Regulator 5 Buck Regulator 5.1 Description The gate of the power switch is driven by the external capacitor connected to pin BDS (Buck Driver Supply) using the bootstrap principle. An integrated under voltage lockout function supervising the ’bootstrap’ capacitor voltage ensures that the device is always driven with a sufficient bootstrap voltage in order to prevent from extensive heat up of the power transistor.
IFX91041 Buck Regulator 5.2 Electrical Characteristics Electrical Characteristics: Buck Regulator VS = 6.0 V to 40 V, Tj = -40 °C to +125°C, all voltages with respect to ground (unless otherwise specified) Pos. 5.2.1 Parameter Output voltage Symbol VFB Limit Values Min. Typ. Max. 4.90 5.00 5.10 Unit Conditions V IFX91041EJV50; VVEN = VS 0.1A < ICC < 1.0A VFB 5.2.2 5.2.3 Output voltage 5.2.4 VFB 4.80 5.00 5.20 V 3.23 VFB 3.17 VFB 3.30 V V 0.588 0.60 0.612 V VFB 0.576 0.
IFX91041 Buck Regulator Electrical Characteristics: Buck Regulator VS = 6.0 V to 40 V, Tj = -40 °C to +125°C, all voltages with respect to ground (unless otherwise specified) Pos. Parameter Symbol Limit Values Unit Conditions Min. Typ. Max. VBDS VBUO Dmax tstart – – 5 V (VBDS - VBUO) increasing – – 100 % 3) 350 500 750 µs VFB rising from 5% to 95% of VFB,nom 5.2.19 Charge pump switch-off threshold 5.2.20 Maximum duty cycle 5.2.21 Soft start ramp 5.2.
IFX91041 Module Enable and Thermal Shutdown 6 Module Enable and Thermal Shutdown 6.1 Description With the enable pin the device can be set in off-state reducing the current consumption to less than 2µA. The enable function features an integrated pull down resistor which ensures that the IC is shut down and the power switch is off in case the pin EN is left open. The integrated thermal shutdown function turns the power switch off in case of overtemperature. The typ.
IFX91041 Module Oscillator 7 Module Oscillator 7.1 Description The oscillator turns on the power switch with a constant frequency while the buck regulating circuit turns the power transistor off in every cycle with an appropriate time gap depending on the output and input voltage. The internal sawtooth signal used for the PWM generation has an amplitude proportional to the input supply voltage (feedforward).
IFX91041 Application Information 8 Application Information Note: The following information is given as a hint for the implementation of the device only and shall not be regarded as a description or warranty of a certain functionality, condition or quality of the device. 8.1 Frequency Compensation The stability of the output voltage can be achieved with a simple RC connected between pin COMP and GND.
IFX91041 Application Information 8.
IFX91041 Application Information 8.
IFX91041 Package Outlines 9 Package Outlines 0.35 x 45˚ 1.27 0.41±0.09 2) 0.2 M 0.08 C Seating Plane C A-B D 8x 0˚...8˚ 0.64 ±0.25 D 1 5 1 6 ±0.2 0.2 M D 8x Bottom View 3 ±0.1 A 8 0.19 +0.06 8˚ MAX. 8˚ MAX. C 0.1 C D 2x 4 8 4 5 2.65 ±0.1 0˚...8˚ 1.7 MAX. Stand Off (1.45) 0.2 +0 -0.1 8˚ MAX. 0.1+0 -0.1 3.9 ±0.11) B 4.9 ±0.11) 0.1 C A-B 2x Index Marking 1) Does not include plastic or metal protrusion of 0.15 max. per side 2) Lead width can be 0.61 max.
IFX91041 Revision History 10 Rev.1.1 Revision History 2011-07-08 Adjustment of Junction Temperature Range in (4.2.6) “Functional Range” on Page 6 to the conditions used in the “Electrical Characteristics” on Page 8 ff (-40°C to 125°C) Rev.1.02 2010-02-23 Editorial change Rev.1.01 2009-10-19 Overview page: Inserted reference statement to TLE/TLF series. Rev.1.0 2009-05-04 Final data sheet Data Sheet 16 Rev. 1.
Edition 2011-07-08 Published by Infineon Technologies AG 81726 Munich, Germany © 2011 Infineon Technologies AG All Rights Reserved. Legal Disclaimer The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics.
