Switched-Capacitor Voltage Inverter with Shutdown

The ADM8828/ADM8829 is a charge-pump voltage inverter which may be used to generate a negative supply from a positive input. Input voltages ranging from +1.5 V to +5.5 V can be inverted into a negative –1.5 V to –5.5 V output supply. This inverting scheme is ideal for generating a negative rail in single power-supply systems. Only two small external capacitors are needed for the charge pump. Output currents up to 25 mA with greater than 99% efficiency are achievable.

The ADM8828 also features a low power shutdown (SHDN) pin. This can be used to disable the device and reduce the quiescent current to 20 nA.

The ADM8828/ADM8829 is available in a 6-lead SOT-23 package.

Applications

* Handheld Instruments

* LCD Panels

* Cellular Phones

* PDAs

* Remote Data Acquisition

* Op Amp Power Supplies

* Inverts Input Supply Voltage

* 99% Voltage Conversion Efficiency

* 25 mA Output Current

* Shutdown Function

* Requires Only Two Capacitors