Product Summary

The 3551S is a fixed frequency, current mode step-up DC/DC converter with two integrated NFETs that can be used for precision LED brightness control. The devices are capable of driving loads up to 1A from a single-cell Li-Ion battery. The 3551S is suitable for (1)White LED Camera Flash; (2)White LED Torch (Flashlight); (3)DSC (Digital Still Camera) Flash; (4)Cellular Camera Phone Flash; (5)PDA Camera Flash; (6)Camcorder Torch (Flashlight) lamp.

Parametrics

3551S absolute maximum ratings: (1)VIN pin: Voltage to GND 7.5V; (2)SW pin: Voltage to GND 21V; (3)FB pin: Voltage to GND 7V; (4)VC pin: Voltage to GND 1.26V ± 0.3V; (5)SD,T/F pins: Voltage to GND 7.5V; (6)FET-T, FET-F: Voltage to GND 6V; (7)Junction Temperature (TJ-MAX )150℃; (8)Storage Temperature Range -65 to +150℃; (9)ESD Rating: 2.0kV.

Features

3551S features: (1)Up to 1A total drive current; (2)Flash timeout protection; (3)Independent Torch/Flash/Shutdown modes; (4)LED disconnect in shutdown; (5)Programmable soft-start limits inrush current; (6)Over-voltage protection; (7)Wide voltage range 2.7 to 5.5V; (8)1.25MHz constant switching frequency; (9)Small, low profile package, non-pullback LLP14 (4mm×4mm).

Diagrams

3551S block diagram

3551-1BS
3551-1BS
Cooper Bussmann
Circuit Breakers BUSS FUSEBLOCK
Data Sheet
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355127-000
355127-000
TE Connectivity
Heat Shrink Tubing & Sleeves 202D132-4/86-0
Data Sheet
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35519-1600
35519-1600
Molex
Headers & Wire Housings 0925 HYBRID FEMALE H HYBRID FEMALE HSG16P
Data Sheet
0-1: $0.74
1-10: $0.67
10-100: $0.53
100-500: $0.44
35515-0311
35515-0311
Molex
Headers & Wire Housings SFPF FEMALE HOUSING FEMALE HOUSING 3P RH
Data Sheet
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3551-5
3551-5
Cooper Bussmann
Circuit Breakers BUSS FUSEBLOCK
Data Sheet
0-1: $69.44
1-5: $66.29
5-10: $63.13
10-25: $59.98
35513-0200
35513-0200
Molex
Automotive Connectors FSM BULB SOCKET RECP LB SOCKET RECPT 2CKT
Data Sheet
Negotiable