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TSM101 integrates in the same 8 pin DIP or SO

package

• 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/ in-

hibited thanks to an external pin.

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.

The “IN+”and “IN-” power inputs of the evalua-

tion 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 connect-

ed 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 con-

nected to the base of the darlington to regulate the

power output.

A diode might be needed on the output of the eval-

uation board in the case of a battery charger appli-

cation 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 :

• Vref = R6/(R6+R7)xVout

eq1

where Vref = 1.24V

Figure 1

EVALUATION BOARD -TECHNICAL NOTE