POWER MANAGEMENT Description
The SC1101 is a versatile, low-cost, voltage-mode PWM controller designed for low output vo...
POWER MANAGEMENT Description
The SC1101 is a versatile, low-cost,
voltage-mode PWM controller designed for low output
voltage DC/DC power supply applications. A simple, fixed-
voltage buck regulator can be implemented using the SC1101 with a minimum of external components. Internal level shift and drive circuitry eliminates the need for an expensive p-channel, high-side switch. The small device footprint allows for compact circuit design.
SC1101
Asynchronous
Voltage Mode PWM Controller
Features
Low cost / small size Switch mode efficiency up to 95% 1% reference
voltage accuracy Over current protection 500mA output drive SO-8 package
SC1101 features include a temperature compensated
voltage reference, triangle wave oscillator, current limit comparator, frequency shift over-current protection, and an internally compensated error amplifier. Pulse by pulse current limiting is implemented by sensing the differential
voltage across an external resistor, or an appropriately sized PC board trace.
Applications
Pentium® P55 Core Supply Low Cost Microprocessor Supplies Peripheral Card Supplies Industrial Power Supplies High Density DC/DC Conversion
The SC1101 operates at a fixed frequency of 200kHz, providing an optimum compromise between efficiency, external component size, and cost.
Typical Application Circuit
+5V
Q1 IRLR3103
L1 R5 4uH 0.05
GND
C1 1.0
C2
C3
150/6.3V 150/6.3V
D2 MBRD1035L
+12V
R1 10
C4 0.1
R2 R3 1k 1k
U1 SC1101
C6
1 VCC
GND 8
0...
