HIGH-EFFICIENCY DC/DC CONVERTER

DESCRIPTION
The UTC 3563 is a monolithic control circuit containing the primary functions required for DC to DC converters and highside-sensed constant current source. The device consists of an internal temperature compensated reference, comparator, controlled duty cycle oscillator with an active current sense circuit, bootstrapped driver, and high current output switch. This device is specifically designed to construct a constant current source for battery chargers with a
minimum number of external components. Bootstrapped driver can drive the NPN output switch
to saturation for higher efficiency and less heat dissipation. The UTC 3563 can deliver 1.5A
continuous current without requiring a heat sink.

FEATURES
*3V to 30V input voltage operation.
*Internal 2A peak current switch.
*1.5A continuous output current.
*Bootstrapped driver.
*High side current sense capability.
*High efficiency (up to 90%)
*Internal ±2% reference.
*Low quiescent current at 1.6mA.
*Frequency operation from 100Hz to 100KHz.

APPLICATIONS
*Constant current source for battery chargers.
*Saver for cellular phones.
*Step-Down DC-DC converter module.