Description
The L6902D is a complete and simple step down switching regulator with adjustable current limit.
Based on a voltage mode structure it integrates a current error amplifier to have a constant voltage and constant current control.
By means of an on board current sense resistor and the availability of the current sense pins (both compatible to Vcc and for Cs- compatible with GND too) a current limit programming is very simple and accurate (±5%). Moreover constant current control can be used to charge NiMH and NiCd batteries.
The device can be used as a standard DC/DC converter with adjustable current limit (set by using the external sense resistor)

Features
■ Up to 1 A output current
■ Operating input voltage from 8 V to 36 V
■ Precise 3.3 V (±2%) reference voltage
■ 5 % output current accuracy
■ Output voltage adjustable from 1.235 V to 34 V
■ 250 kHz internally fixed frequency
■ Voltage feedforward
■ Zero load current operation
■ Adjustable current limit
■ Protection against feedback Disconnection
■ Thermal shutdown

Applications
■ Chargers for NiCd, NiMH batteries and preregulator for lithium-ion batteries
■ Adjustable current generator
■ Simple step-down converters with adjustable current limit
■ Battery equipped systems
■ Distributed power supply
■ Mobile PC and subnotebook