SA58780

INTEGRATED CIRCUITS SA58780 Sense current amplifier with selectable gain Product data Supersedes data of 2002 Dec 10 2003 Nov 10 Philips Semiconductors Philips Semiconductors Product data Sense current amplifier with selectable gain SA58780 GENERAL DESCRIPTION The SA58780 is a single amplifier that allows current sensing independent of the supply voltage. The input offset voltage is typically ±500 µV with typical offset drift of ±6 µV/°C. The SA58780 supply current is typically 150 µA and it operates from 3.0 V to 24 V single supply. The input common mode range is selectable for high and low ranges. The amplifIer gain is user selected for a “High” of 100 V/V or a “Low” of 50 V/V. The SA58780 is ideal for battery charger applications in notebook computers and PDAs. FEATURES Supply voltage range: 3 V to 24 V Low supply current: 150 µA (typical) Low input offset voltage: ±500 µV (typical) Low input offset drift: ±6 µV/°C (typical) Power supply rejection ratio (1 kHz): 80 dB (typical) Common mode rejection ratio (1 kHz): 100 dB (typical) Common mode input range selection: Amplifier gain selection: 1.8 V to 24 V (ISEL HIGH); –0.3 V to VCC – 2.4 V (ISEL LOW) GSEL HIGH: GV = 100 V/V; GSEL LOW: GV = 50 V/V APPLICATIONS Notebook computers Personal digital assistants (PDA) SIMPLIFIED DEVICE DIAGRAM TO CHARGE RS ISEL 1 INPUT CONTROL HIGH IN– 2 H V/I CONVERTER IN+ 3 LOW R 200 kΩ L R 194 kΩ R 6 kΩ R 15 kΩ R 5 kΩ H R 55 kΩ L OUT TO BATTERY SA58780 GAIN CON...