February 2008 Rev 3 1/15
15
TSM1051
Constant voltage and constant current controller
for battery chargers and adaptors
Features
■ Constant voltage and constant current control
■ Low voltage operation
■ Precision internal voltage reference
■ Low external component count
■ Current sink output stage
■ Easy compensation
■ Low AC mains voltage rejection
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
■ Adaptors
■ Battery chargers
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
www.st.com
Obsolete Product(s) - Obsolete Product(s)
