FEATURES
s s s s s s s s s s s s DESCRIPTIO 1.5A Switch Current High Efficiency—Low Loss 0.2Ω Switch Constant 200kHz Switching Frequency 4V to 15V Input VoltageRange Minimum Output: 1.21V Low Supply Current: 1.9mA Low Shutdown Current: 20µA Easily Synchronizable Up to 400kHz Cycle-by-Cycle Current Limit Reduced EMI Generation Low Thermal Resistance SO-8 Package Uses Small Low Value Inductors The LT ®1578 is a 200kHz monolithic buck mode switching regulator. A 1.5A switch is included on the die along with all the necessary oscillator, control and logic circuitry. The topology is current mode for fast transient response and good loop stability. It will operate over a 4V to 15V input range. In addition, the reference voltage has been lowered to allow the device to produce output voltages down to 1.2V. Quiescent current has been reduced by a factor of two. Switch on resistance has been reduced by 30%. Switch transition times have been slowed to reduce EMI generation. The oscillator frequency has been reduced to 200kHz to maintain high efficiency over a wide output current range.