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Summary of Contents for DC1544

Page 1: ...ternal n channel power switch provides efficiency as high as 95 in typical boost applications with 14 4W output The LT3957 datasheet gives a complete description of the part operation and applications information The datasheet must be read in conjunction with this Quick Start Guide for demonstration circuit 1544A The LT3957 is assembled in a 36 lead plastic UHE package with two thermally enhanced ...

Page 2: ...he following positions NO SYNC 2 With power off connect the input power supply to VIN and GND NOTE Connect power to GND not SGND 3 Connect a load of 600mA or less to VOUT and GND terminals not SGND 4 Turn on the power at the input NOTE Make sure that the input voltage does not exceed 20V 5 Check for the proper output voltage 24V NOTE If there is no output temporarily disconnect the load to make su...

Page 3: ... down by tying EN UVLO to GND The EN UVLO pin is already being used as an undervoltage lockout threshold for the VIN with resistors R1 and R2 Undervoltage lock out stops the IC from switching when VIN is too low but shutdown further reduces the VIN pin quiescent current when EN UVLO is tied directly to GND It is okay to leave the EN UVLO terminal floating INTVCC is provided as a terminal to be abl...

Page 4: ...APACITORS AND RESISTORS ARE 0402 2 ALL CAPACITOR VALUES ARE IN MICROFARADS 3 ALL RESISTOR VALUES ARE IN OHMS E3 VIN 4 5V 20V E2 SGND C10 OPT R7 0 C4 4 7uF 50V C6 50V 4 7uF R3 6 8k R5 226k 0402 1 E9 SGND E7 GND E10 GND U1 LT3957EUHE FBX 31 G N D 17 G N D 14 G N D 16 SYNC 34 RT 33 G N D 15 INTVCC 28 SW 38 V IN 27 EN UVLO 25 VC 30 SS 32 SG N D 37 SW 21 G N D 13 G N D 12 SG N D 4 SG N D 23 SW 8 SENSE2...

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