L6910GTR STMicroelectronics, L6910GTR Datasheet

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... ADJUSTABLE STEP DOWN CONTROLLER WITH SYNCHRONOUS RECTIFICATION Figure 1. Packages Table 1. Order Codes Part Number L6910GTR dc-dc conversion from 3.3V, 5V and 12V buses. The output voltage is adjustable down to 0.9V; higher voltages can be obtained with an external voltage divider. High peak current gate drivers provide for fast switch- ing to the external power section, and the current can be in excess of 20A ...

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L6910G Table 2. Absolute Maximum Ratings Symbol Vcc Vcc to GND, PGND V -V Boot Voltage BOOT PHASE V -V HGATE PHASE OCSET, LGATE, PHASE SS, FB, PGOOD, VREF, EAREF, RT COMP T Junction Temperature Range j T Storage temperature ...

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Table 4. Pins Function Pin Name 1 VREF Internal 0.9V ±1.5% reference is available for external regulators or for the internal error amplifier (connecting this pin to EAREF) if external reference is not available. A minimum 1nF capacitor is required. ...

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L6910G Table 5. Electrical Characteristics (V Symbol Parameter V SUPPLY CURRENT cc Icc Vcc Supply current POWER-ON Turn-On Vcc threshold Turn-Off Vcc threshold Rising V threshold OCSET Turn On EAREF threshold SOFT START AND INHIBIT Iss Soft start Current S.S. ...

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DEVICE DESCRIPTION The device is an integrated circuit realized in BCD technology. The controller provides complete con- trol logic and protection for a high performance step-down DC-DC converter designed to drive N Channel Mosfets in a synchronous-rectified ...

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L6910G 4.2 Reference A precise ±1.5% 0.9V reference is available. This reference must be filtered with 1nF ceramic capacitor to avoid instability in the internal linear regulator able to deliver up to 100µA and may be used as ...

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PHASE pin is over about 500mV. The lower mos is in any case turned-on after 200ns from the high side turn-off. The peak current is shown for both the upper (fig. 6) and the lower (fig. 7) ...

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L6910G Overcurrent protection is performed by the device comparing the drop across the high side MOS, due to the R , with the voltage across the external resistor (R DSON upper MOS. Thus the overcurrent threshold (I Where the typical ...

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The response time to a load transient is different for the application or the removal of the load: if during the ap- plication of the load the inductor is charged by a voltage equal to the difference between the input ...

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L6910G Figure 10. Compensation Network The compensation network consists in the internal error amplifier and the impedance networks Z C20) and Z (R5, C18 and C19). The compensation network has to provide a closed loop transfer function with FB the ...

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Figure 11. Asymptotic Bode Plot of Converter's Gain 5 15A DEMO BOARD DESCRIPTION The demo board shows the operation of the device in a general purpose application. This evaluation board al- lows voltage adjustability from 0. through the ...

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L6910G Table 6. Part List Reference R1 R2 10K R3 4.7K R4 1KOhm 5% 125mW R5 2.7K R6 10Ohm 5% 125mW R7 510Ohm 5% 125mW R8 R9 R10 14K R11 6.98K R12 2.61K R13 1.74K C1, C3 C9, C10 C12, ...

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Figure 13. PCB and Components Layouts Component Side Figure 14. PCB and Components Layouts Internal Power GND Layer Figure 15. Efficiency vs Output Current 100 100 Vin=Vcc=5V Vin=Vcc=5V Fsw=200KHz Fsw=200KHz 75 75 ...

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L6910G Figure 16. Efficiency vs Output Current 100 COMPONENTS SELECTION 6.1 Inductor Selection To select the right inductor value, the application conditions must be fixed. For example we ...

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APPLICATION SUGGESTIONS FOR HIGHER CURRENTS For higher output currents 20A, the following configuration can be used (with reference to the demo board schematic): Q1,Q2,Q3: STS11NF30L Q4,Q5,Q6: STS17NF3LL L: 2.5µH Magnetic 77121A7 Core 7T 2x AWG16 In these ...

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L6910G Table 9. Part List Reference Description Resistor R1 2K7 Ohm 0805 5% 125mW 1K8 Ohm 0805 5% 125mW 1K Ohm 0805 5% 125mW R2 10K 5% 125mW R3 4K7 5% 125mW R4 4K7 5% 125mW R5 2K7 5% 125mW ...

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Figure 18. PCB and Components Layouts Component Side 7.1 Compact Demo Board Performances Figures 19, 20 show the measured efficiency versus load current for different values of output voltage. The mea- sure has been done at 5V and 12V input. ...

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L6910G 8 APPLICATION IDEA 1: DDR MEMORY AND TERMINATION SUPPLY Double Data Rate (DDR) Memories require a particular Power Management Architecture. This is due to the fact that the trace between the driving chipset and the memory input must be ...

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Figure 22. Efficiency vs Output Current Source Mode Vcc=12V Vcc=12V Vout=1.25V Vout=1.25V Fsw=200KHz Fsw=200KHz ...

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L6910G 9 APPLICATION IDEA 2: POSITIVE BUCK-BOOST REGULATOR 3V TO 13.2V INPUT / 5V 2.5A OUTPUT In some applications the input voltage changes in a very wide range while the output must be regulated to a fixed value. In this ...

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Table 11. Part List Reference R1 910 Ohm 5% 125mW R2 R3 4.7K 5% 125mW R4 R5 2.7K 5% 125mW Ohm 125mW C1,C2 C13,C14 C12,C5, C10 C11 G1 L1 2.5µH (77121A7 Core, ...

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L6910G 10 APPLICATION IDEA 3: BUCK-BOOST REGULATOR 3V TO 5.5V INPUT/-5V 3A OUTPUT In applications where a negative output voltage is required, a standard Buck-Boost topology can be implement- ed. The considerations related to the maximum output current are the ...

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Table 12. Part List (continued) C9 C10 Reference C11 G1 L1 2.5µH (77121A7 Core, Double winding 7 AWG16) Q1, STPS3L25U ( STPS340U) U1 Figure 31. Efficiency vs. Output Current ...

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L6910G Figure 32. SO-16 (Narrow) Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 1.75 a1 0.1 0.25 a2 1.6 b 0.35 0.46 b1 0.19 0.25 C 0.5 c1 45° (1) 9 5.8 6.2 e ...

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Table 1. Revision History Date Revision May 2005 1 First Issue Description of Changes L6910G 25/26 ...

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... No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics ...