SM6781BV

SM6781BV NIPPON PRECISION CIRCUITS INC. Ni-MH/Ni-Cd Battery Charger IC OVERVIEW The SM6781BV is a quick charge control IC for Nickel Metal Hydride (NiMH) and Nickel-Cadmium (NiCd) rechargeable batteries. Quick charging ends in response to negative delta voltage detection (–∆V) and maximum charging time detection functions. Also, quick charge mode is placed on hold if the battery voltage becomes abnormal, until normal conditions are restored. The SM6781BV requires few external components to realize a high-stability quick charge battery charger. FEATURES I I PINOUT (Top view) pre lim ina I I I I I I Ni-MH/Ni-Cd battery quick charge control −∆V and maximum charge time cutoffs 15min (typ) −∆V detection invalid time – 4mV (typ) −∆V detection accuracy Inhibit function Charge condition LED indicator output (on, pulsed, off) Low power dissipation standby mode (< 1µA) 8-pin VSOP package ORDERING INFORMATION Device Package SM6781BV 8-pin VSOP PACKAGE DIMENSIONS (Unit: mm) ry TIME CHGN INH NC VDD LEDN BATT VSS TBD NIPPON PRECISION CIRCUITS—1 SM6781BV BLOCK DIAGRAM VDD DC Input Current Source Reference Regulators BATT Max/Min Cell-voltage Check Battery Pack INH OSC Number 1 Name TIME lim I/O I O I – Ground – Supply – I No connection (must be open) O PIN DESCRIPTION Timer mode select input (3-level) HIGH and LOW levels applied using pull-up and pull-down, respectively. MID-level is applied using a voltage divider resistor network with voltage VDD/2. Charge sta...