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)
Variable oscillator frequency 300KHz (max)
1.25V voltage reference Output
Pin Descriptions
Name
Output
Vcc
Comp.
FB
SCP
SS
CT
Gnd
PWM Output
Supply Voltage
Feedback Loop Compensation
Voltage Feedback
Short Circuit Protection
Soft Start
Timing Capacitor
Ground
Description
Applications
LCD Monitor
xD-ROM, xDSL product
DC to DC converters in computers
Backlight inverter
Ordering Information
Part No.
TS3404CS
TS3404CD
Operating Temp.
(Ambient)
-20 ~ +85 C
o
Package
SOP-8
DIP-8
Absolute Maximum Rating
Supply Voltage
Amplifier Input Voltage
Collector Output Voltage
Source Current
Sink Current
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature 1.6mm(1/16鈥? from case for 10Sec.
V
CC
V
I
V
O
I
SOURCE
I
SINK
T
J
T
STG
T
LEAD
28
20
Vcc~1.0V
200
200
-20 ~ +150
-65 ~ +150
260
V
V
V
mA
mA
o
o
o
C
C
C
TS3404
1-5
2003/12 rev. A