7.1 Overview

The MC33063A and MC34063A devices are easy-to-use ICs containing all the primary circuitry needed for building simple DC-DC converters. These devices primarily consist of an internal temperature-compensated reference, a comparator, an oscillator, a PWM controller with active current limiting, a driver, and a high-current output switch. Thus, the devices require minimal external components to build converters in the boost, buck, and inverting topologies.

The MC33063A device is characterized for operation from –40°C to 85°C, while the MC34063A device is characterized for operation from 0°C to 70°C.

7.2 Functional Block Diagram

7.3 Feature Description

• Wide Input Voltage Range: 3 V to 40 V
• High Output Switch Current: Up to 1.5 A
• Adjustable Output Voltage
• Oscillator Frequency Up to 100 kHz
• Precision Internal Reference: 2%
• Short-Circuit Current Limiting
• Low Standby Current

7.4 Device Functional Modes