MC34063

MC34063 DC/DC CONVERTER CONTROL CIRCUIT Description The MC34063 is a monolithic control circuit containing the primary functions required for DC/DC converters. The device consists of an internal temperature compensated reference, comparator, controlled duty cycle oscillator with an active current limit circuit, driver and high current output switch. This device is specifically designed to be incorporated in stepdown, step-up and voltage-inverting applications with a minimum number of external components. The ±2% internal reference and low quiescent current of 1.6mA are among the improvements of the device over the competition Features  3V to 30V Input Voltage Operation.  Internal 1.2A Peak Current Switch.  Internal ±2% Reference.  Low Quiescent Current at 1.6mA.  Frequency Operation from 100Hz to 100KHz.  Low Dropout Operation: 100% Duty Cycle  Current Limiting.  Standard SOP8/DIP8 Packages Applications  DC-DC Converter Module  ADSL Modems  Hub.  Battery Chargers Functional Diagram Ver1.0 1 Pin Description Symbol Pin NO. MC34063 Description SC SE TC GND FB VCC IPK DRI 1 1.2A switch collector 2 Darlington switch emitter 3 Oscillator timing capacitor 4 Power GND 5 Feedback comparator inverting input 6 Power supply input 7 Highside current sense input, VCC - VIPK=300mV 8 Drive collector Absolute Maximum Ratings Supply Voltage ……………….……………………. ………………………………… ……40V Comparator Input Voltage Range ……………………….……..………………………-0.3V~40V Switch Collector Voltage …………………...