TPS6735

TPS6735 FIXED NEGATIVE 5ĆV 200ĆmA INVERTING DC/DC CONVERTER D Negative 5-V 200-mA Output (VCC ≥ 4.5 V) D 4-V to 6.2-V Input Operating Range D 78% Typical Efficiency D 160-kHz Fixed-Frequency Current-Mode PWM Controller D EN Input Inhibits Operation and Reduces Supply Current to 1 µA D Soft Start D 8-Pin SOIC and DIP Packages D −40°C to 85°C Free-Air Temperature Range D Pin-for-Pin Compatible with MAX735 SLVS141A − JULY 1996 − REVISED JANUARY 1997 D OR P PACKAGE (TOP VIEW) EN 1 REF 2 SS 3 COMP 4 8 VCC 7 OUT 6 GND 5 FB description The TPS6735 is a fixed negative 5-V output inverting dc/dc converter capable of delivering 200 mA from inputs as low as 4.5 V. The only external components required are an inductor, an output filter capacitor, an input filter capacitor, a reference filter capacitor, and a Schottky rectifier. An enable input is provided to shut down the inverter when a −5-V output is not needed. The typical supply current is 1.9 mA at no-load and is further reduced to 1-µA when the enable input is low. The TPS6735 is a 160-kHz current-mode pulse-width-modulation (PWM) controller with a p-channel MOSFET power switch. The gate drive uses the −5-V output to reduce the die area needed to realize the 0.4-Ω MOSFET. Soft start is accomplished with the addition of one small capacitor at SS. A 1.22-V reference is available for external loads up to 125 µA. The TPS6735 is attractive for board-level dc/dc conversion in computer peripherals and in battery-powered equipment req...