SM8303 Datasheet, PDF (1/11 Pages) SamHop Microelectronics Corp. – 150KHz, 3A PWM Buck Switching Regulator

SAMHOP Microelectronics Corp.
150KHz, 3A PWM Buck Switching Regulator
SM8303
General Description
The SM8303 is a monolithic integrated circuit that
provide all the active functions for a step-down
switching regulator, capable of driving a 3A load
without additional transistor component. Requiring
a minimum number of external component, the
board space can be saved easily. The external
shutdown function can be controlled by TTL logic
level and then come into standby mode. The
internal compensation makes feedback control
have good line and load regulation without external
design. Regarding protected function, thermal
shutdown is to prevent over temperature operating
from damage, and current limit is against over
current operating of the output switch. The SM8303
operates at a switching frequency of 150KHz thus
allowing smaller sized filter components than what
would be needed with lower frequency switching
regulators. Other features include a guaranteed
+4% tolerance on output voltage under specified
input voltage and output load conditions, and +15%
on the oscillator frequency. The output version
included fixed 3.3V, 5V, 12V, and an adjustable
type. The packages are available in a standard
5-lead TO-220(T) package and a 5-lead TO-263(S).
Features
- 3.3V, 5V, 12V and adjustable output versions
- Adjustable version output voltage range, 1.23V to
28V +4% max over line and load condition
- Available in TO220-5L and TO263-5L packages
- Voltage mode non-synchronous PWM control
- Thermal-shutdown and current-limit protection
- ON/OFF shutdown control input
- Input voltage range up to 32V
- Output load current: 3A
- 150KHz fixed frequency internal oscillator
- Low power standby mode
- Built-in switching transistor on chip
Applications
- Simple High-efficiency step-down(buck) regulator
- Efficient preregulator for linear regulators
- On-card switching regulators
- Positive to negative converter
- Battery Charger
Pin Assignments
( Top View )
Metal Tab GND
TO263-5L
5 SD
4 FB
3 Gnd
2 Output
1 V_IN
( Top View )
TO220-5L
5 SD
4 FB
3 Gnd
2 Output
1 V_IN
Pin Descriptions
Name
V_IN
Output
Gnd
FB
SD
Description
Operating voltage input
Switching output
Ground
Output voltage feedback control
ON/OFF Shutdown
1
V1.0 May 17 ,2007