
Maxim Integrated
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