TSM1052_08 Datasheet, PDF (1/15 Pages) STMicroelectronics – Constant voltage and constant current controller for battery chargers and adapters

TSM1052
Constant voltage and constant current controller
for battery chargers and adapters
Features
■ Secondary-side constant voltage and constant
current control
■ Very low voltage operation
■ Very low quiescent consumption
■ High-accuracy internal reference
■ Low external component count
■ Wired-or open-drain output stage
■ Easy frequency compensation
■ SOT23-6 micro package
Applications
■ Battery chargers
■ AC DC adapters
Description
The TSM1052 is a highly integrated solution for
SMPS applications requiring a dual control loop to
perform CV (constant voltage) and CC (constant
current) regulation.
The TSM1052 integrates a voltage reference, two
op amps (with OR-ed open-drain outputs), and a
low-side current sensing circuit.
The voltage reference, along with one op amp, is
the core of the voltage control loop; the current
sensing circuit and the other op amp make up the
current control loop.
SOT23-6
The external components needed to complete the
two control loops are:
■ A resistor divider that senses the output of the
power supply (adapter, battery charger) and
fixes the voltage regulation set point at the
specified value;
■ A sense resistor that feeds the current sensing
circuit with a voltage proportional to the dc
output current; this resistor determines the
current regulation set point and must be
adequately rated in terms of power dissipation;
■ Frequency compensation components
(RC networks) for both loops.
The TSM1052, housed in one of the smallest
package available, is ideal for space-shrunk
applications such as adapters and chargers.
Table 1.
Device summary
Part number
TSM1052
Package
SOT23-6
Packaging
Tape and reel
February 2008
Rev 2
1/15
www.st.com
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