TDA1060N

29/10/2012

COMSET SEMICONDUCTORS

1 | 3

CONTROL CIRCUIT FOR SMPS

GENERAL DESCRIPTION

The TDA1060N is a bipolar integrated circuit intended for the control of a switched-mode

power supply.

QUICK REFERENCE DATA

Symbol

Ratings

Value

Unit

Supply voltage (voltage source)

< 18

V

Supply current (current source)

<30

mA

Output current

<40

mA

Output current

<40

mA

Operating ambiant temperature range

-25 to 85

°C

FUNCTIONAL DESCRIPTION

The TDA1060N contains the control loop for a fixed-frequency pulse-duration regulated

SMPS. The device works as follows. The output voltage Vo of the SMPS is sensed via a

feedback network and compared with an internal reference voltage Vref. Any difference

between Vo and Vref is amplified and fed to a pulse-width modulator (PWM), where it is

compared with the instantaneous level of a ramp waveform (sawtooth) from an oscillator.

The output from the PWM is a rectangular waveform synchronized with the oscillator

waveform ; its duty factor depends on the difference between Vo and Vref. This signal drives

the base of the SMPS power switching transistor so that its conduction period and hence the

amount of energy transferred from the input to the output of the SMPS is controlled, resulting

in a constant output voltage.