TSM121 Datasheet, PDF (1/12 Pages) STMicroelectronics – SINGLE CHIP PWM & HOUSEKEEPING IC FOR HALF BRIDGE SMPS

TSM121
SINGLE CHIP PWM & HOUSEKEEPING IC
FOR HALF BRIDGE SMPS
s HOUSEKEEPING CIRCUIT :
s Over voltage protection for 3.3V, 5V and 12V
without external components
s Additional Over voltage protection (-5V and/
or -12V, or Primary Over Power control) with
external components
s Under voltage protection for 3.3V, 5V and
12V without external components
s Over current protection for 3.3V, 5V and 12V
with internal threshold voltage
s Externally adjustable Inrush Current blanking
during transients
s Externally adjustable Under voltage blanking
during Power Up
s Power Good output
s Externally adjustable PG delay
s Remote input
s Externally adjustable Remote delay
s Internal Precision Voltage Reference (Vref1)
s PWM GENERATOR :
s Error Amplifier (easy compensation)
s Oscillator (adjustable frequency)
s PWM generation
s Soft Start & Dead Time Control (adjustable)
s Open collector outputs for indirect Pulse
Transformer driving
s Precision Voltage Reference (Vref2) (Uncom-
mitted with Vref1)
DESCRIPTION
The TSM121 integrated circuit incorporates all
sensing circuit to regulate and protect from over
voltage, under voltage and over current a multiple
output power supply (12V, 5V, 3.3V).
TSM121 incorporates all the necessary functions
for proper PWM generation and pulse transformer
drive to be adapted easily in the PC SMPS power
supplies, and all the Housekeeping features which
allow safe operation in all conditions, and very
high integration.
TSM121 integrates two independent Voltage Ref-
erences which are uncommitted to ensure safe
Regulation and Protection by the same chip.
APPLICATION
s Primary PWM and secondary housekeeping
in PC/Server SMPS using Half Bridge topol-
ogy
ORDER CODE
Part Temperature
Number
Range
TSM121C 0 to 85°C
N = Dual in Line Package (DIP)
Package
N
•
Marking
TSM121C
N
DIP24 shrink
(Plastic Package)
PIN CONNECTIONS (top view)
C1 1
VCC 2
FB 3
IN- 4
IN+
5
REM 6
TREM 7
TPG 8
PG 9
IS12 10
IS5 11
IS33 12
24 C2
23 SS/DTC
22 OSC
21 GND
20 VREF2
19 TSUR
18 TUV
17 PI
16 EP
15 VS12
14 VS5
13 VS33
January 2001
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