AP1534

• Product Introduction

AP1534The buck switch regulates PWM control

description The AP1534 includes a buck switch to regulate PWM control. The devices include a reference voltage source, oscillation circuitry, error amplifier, internal PMOS. The AP1534 provides a low-ripple power supply, high efficiency, and excellent transient characteristics. The PWM control circuit is capable of changing the duty cycle linearity from 0 to 99%. The converter also contains an error amplifier circuit as well as a soft-start circuit to prevent overshoot during start-up. Built-in enable function, overcurrent protection function and short circuit protection function will reduce the operating frequency from 300kHz to 50kHz when OCP or SCP occurs. In addition, the internal compensation block is built to minimize the number of external components. With internal P-channel power MOS, coils, capacitors and external diodes, these chips can also be used as buck switching regulators. Standout features such as low current consumption offered in a small SO-8 package, coupled with their service as an ideal power supply unit for portable devices. Since the converter can accommodate input voltages up to 18V, it is also suitable for operation via an AC adapter. Features and Benefits: • Input Voltage: 3.6V to 18V • Output Voltage: 0.8V to V CC • Duty Cycle: 0% to 99% PWM Control • Oscillation Frequency: Typical at 300KHz • Current Limit, Enable Function • Thermal Shutdown Function • Built-in P-Channel MOS with Internal Switch • SO-8: In "Green" Molded Compound (Bromination-Free, Antimony-Free) • Lead-Free Finish/RoHS Compliant apply • Computer motherboards • LCD displays • Graphics cards • DVD video players • Telecommunications equipment • ADSL modems • Printers and other peripherals • Microprocessor cores for power supply