General Description

The ultra-small MAX1719/MAX1720/MAX1721 monolithic, CMOS charge-pump inverters accept input voltages ranging from +1.5V to +5.5V. The MAX1720 operates at 12kHz, and the MAX1719/MAX1721 operate at 125kHz. High efficiency, small external components, and logic controlled shutdown make these devices ideal for both battery-powered and board-level voltage conversion applications.

Oscillator control circuitry and four power MOSFET switches are included on-chip. A typical MAX1719/MAX1720/MAX1721 application is generating a -5V supply from a +5V logic supply to power analog circuitry. All three parts come in a 6-pin SOT23 package and can deliver a continuous 25mA output current.

Features

♦ 1nA Logic-Controlled Shutdown

♦ 6-Pin SOT23 Package

♦ 99.9 Voltage Conversion Efficiency

♦ 50µA Quiescent Current (MAX1720)

♦ +1.5V to +5.5V Input Voltage Range

♦ 25mA Output Current

♦ Requires Only Two 1µF Capacitors (MAX1719/MAX1721)

Applications

  Local Negative Supply from a Positive Supply

  Small LCD Panels

  GaAs PA Bias Supply

  Handy-Terminals, PDAs

  Battery-Operated Equipment