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TS3404
1-5
2003/12 rev. A
TS3404
PWM Buck Controller
Pin assignment:
1. Out
2. Vcc
3. Comp.
4. FB
5. SCP
6. SS
7. CT
8.
Gnd
Supply Voltage Range 3.6V to 27V
Output Driving Current 200mA
Oscillator Frequency up to 300KHz
General Description
The TS3404 integrates Pulse Width Modulation (PWM) control circuit into a single chip, and makes simple work out of
implementing a complete control and protection scheme for a DC-DC step-down converter. The TS3404 provides simple
feedback loop compensation, 1.25V reference output, error amplifier, adjustable oscillator, soft start, under voltage lock
out (UVLO), short circuit protection(SCP) circuitry, and push pull output circuit.
The TS3404 is design for adjustable switching frequency by trimming time capacitor (CT), during low supply voltage
situation, the under voltage lock out (UVLO) makes sure that the output are off until the internal circuit operates normally.
The TS3404 is offered in DIP-8 and SOP-8 package.
Features
PWM buck control circuit
Operating voltage can be up to 27V
Under voltage lock out (UVLO) protection
Soft start (SS) circuit
Short circuit Protection (SCP)
1.25V voltage reference Output
Variable oscillator frequency 300KHz (max)
Pin Descriptions
Name
Output
Vcc
Comp.
FB
SCP
SS
CT
Gnd
Description
PWM Output
Supply Voltage
Feedback Loop Compensation
Voltage Feedback
Short Circuit Protection
Soft Start
Timing Capacitor
Ground
Applications
LCD Monitor
xD-ROM, xDSL product
Backlight inverter
DC to DC converters in computers
Ordering Information
Part No.
Operating Temp.
(Ambient)
-20 ~ +85
o
C
Package
TS3404CS
TS3404CD
SOP-8
DIP-8
Absolute Maximum Rating
Supply Voltage
V
CC
28
V
Amplifier Input Voltage
V
I
20
V
Collector Output Voltage
V
O
Vcc~1.0V
V
Source Current
I
SOURCE
200
mA
Sink Current
I
SINK
200
mA
Operating Junction Temperature Range
T
J
-20 ~ +150
o
C
Storage Temperature Range
T
STG
-65 ~ +150
o
C
Lead Temperature 1.6mm(1/16”) from case for 10Sec.
T
LEAD
260
o
C