TSM101A STMicroelectronics, TSM101A Datasheet - Page 11

• Manufacturer Part Number: TSM101A
• Description: VOLTAGE AND CURRENT CONTROLLER
• Manufacturer: STMicroelectronics

TSM101 integrates in the same 8 pin DIP or SO
package
An immediate way to take advantage of the high
integration and reliability of TSM101 is to use it as
a voltage and current controller on power supplies
secondary. The application note AN896 describes
precisely how to use TSM101 in an SMPS battery
charger.
The TSM101 Evaluation Board is adaptable to any
power supply or battery charger (SMPS or linear)
as a voltage and current controller with minimal
constraints from the user.
HOW TO USE THE TSM101 EVALUATION
BOARD ?
The generic Electrical Schematic is shown on fig-
ure 1. It represents an incomplete SMPS power
supply where the primary side is simplified.
Figure 1
one 1.24V precision voltage reference
two operationnal amplifiers
two diodes which impose a NOR function on the
outputs of the operationnal amplifiers
one current source which can be activated/ inhib-
ited thanks to an external pin.
EVALUATION BOARD - TECHNICAL NOTE
The ”IN+”and ”IN-” power inputs of the evalu-
ation board should be connected directly to the
power lines of the power supply secondary.
The ”Vcc” input of the evaluation board should be
connected to the auxiliary supply line.
In the case of an SMPS power supply, the ”Reg”
output of the evaluation board should be con-
nected to the Optocoupler input to regulate the
PWM block in the primary side. In the case of a
linear power supply, the ”Reg” output should be
connected to the base of the darlington to regulate
the power output.
A diode might be needed on the output of the
evaluation board in the case of a battery charger
application to avoid the discharge of the battery
when the charger is not connected.
COMPONENTS CALCULATIONS
The voltage control is given by the choice of the
resistor bridge R6/R7 (and the trimmer P1) due to
equation 1 :
where Vref = 1.24V
Vref = R6/(R6+R7)xVout
TSM101/A
eq1
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