February 2008

Rev 3

1/15

15

TSM1051

Constant voltage and constant current controller

for battery chargers and adaptors

Features

Description

The device is is a highly integrated solution for

SMPS applications requiring CV (constant

voltage) and CC (constant current) mode.

It integrates one voltage reference, two

operational amplifiers (with ORed outputs -

common collectors), and a current sensing circuit.

The voltage reference combined with one

operational amplifier makes it an ideal voltage

controller; the current sensing circuit and the

other operational amplifier make up the current

control loop.

The only external components are:

– A resistor divider to be connected to the

output of the power supply (adaptor, battery

charger) to set the voltage regulation by

dividing the desired output voltage to match

the internal voltage reference value.

– A sense resistor having a value and

allowable dissipation power which need to

be chosen according to the internal voltage

threshold.

– Optional compensation components (RC).

Housed in one of the smallest package available,

it is ideal for space-shrunk applications such as

adaptors and battery chargers.

Applications

SO-8

SOT23-6

Table 1.

Device summary

Order codes

Package

Packaging

TSM1051CLT

SOT23-6

Tape and reel

TSM1051CD

SO-8

Tube

TSM1051CDT

SO-8

Tape and reel

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