Description

A6902D

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Description

The A6902D 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.

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). The internal robust P-channel DMOS transistor with a

typical of 250 m

Ω assures high efficiency and a minimum dropout even at high output

current level. The internal limiting current (latched function) of typical value of 2.5 A protects

the device from accidental output short circuit avoiding dangerous loads damage. If the

temperature of the chip goes higher than a fixed internal threshold (150 °C with 20 °C

hysteresis), the power stage is turned off.

Other protections beside thermal shutdown complete the device for a safe and reliable

application: overvoltage protection, frequency folback overcurrent protection and protection

vs. feedback disconnection. The internal fixed switching frequency of 250 kHz, and the

SO-8 package pin allow to built an ultra compact DC/ DC converter with a minimum board

space.