SC1133CT is a combination switching controller and low dropout regulator by Semtech. This appears to be the adjustable version of this part.
DESCRIPTION: The SC1133 incorporates a high current low dropout linear regulator section together with a switching buck mode controller. This unique combination is well suited for high current low voltage power supply applications such as the Intel Pentium P55, AMD K6 and the Cyrix M2 processors. The SC113X was designed to reduce the number of components required to design a dual power supply for multivoltage processor applications.
Switching Controller Section: The switching control section is a voltage mode controller designed for high current, low voltage power supply applications. Key features include a temperature compensated voltage reference, triangular oscillator and an internally compensated transconductance error amplifier. The switching controller operates at a fixed frequency of 200kHz, providing an optimum compromise between size, efficiency and cost in the intended application areas.
Linear Section: The linear portion is a high performance positive voltage regulator designed for use in applications requiring "very low dropout performance" at 1.5, 3, 5 and 7.5 amps. Additionally, the linear section provides excellent regulation over variations due to changes in line, load or temperature.
PIN CONFIGURATION:
Pin/Pin Function
1 MOSFET Driver Output
2 Switching Power Ground
3 Error Amplifier Input (Switcher)
4 Signal Ground
5 +12V Input Voltage
6 Vout (Linear Section)
7 +5V Input Voltage
FEATURES:
- 85% typical efficiency for switching section
- Grounded tab
- Thermal shutdown
- Internal short circuit protection
- 7 pin TO-220 package
APPLICATIONS:
- Microprocessor supplies
- Modules supplies
- 1.3V to 3.5V power supplies
- Dual power supplies from 5V source
This part is new and unused -- from manufacturer's original packaging.

