The MAX660ESA monolithic, charge-pump voltage inverter converts a +1.5V to +5.5V input to a corresponding-1.5V to -5.5V output. Using only two low-costcapacitors, the charge pump's 100mA output replaces switching regulators, eliminating inductors and their associated cost, size, and EMI. Greater than 90% efficiency over most of its load-current range combined with a typical operating current of only 120μA provides ideal performance for both battery-powered and board-level voltage conversion applications. The MAX660ESA can also double the output voltage of an input power supply or battery, providing +9.35V at 100mA from a +5V input. A frequency control (FC) pin selects either 10kHz typ or 80kHz typ (40kHz min) operation to optimize capacitor size and quiescent current. The oscillator frequency can also be adjusted with an external capacitor ordriven with an external clock. The MAX660ESA is a pin-compatible, high-current upgrade of the ICL7660. The MAX660ESA is available in both 8-pin DIP and small-outline packages in commercial, extended, and military temperature ranges. For 50mA applications, consider the MAX860/MAX861 pin-compatible devices (also available in ultra-small μMAX packages).
Feature
- Small Capacitors
- 0.65V Typ Loss at 100mA Load
- Low 120μA Operating Current
- 6.5Ω Typ Output Impedance
- Guaranteed ROUT < 15Ω for C1 = C2 = 10μF
- Pin-Compatible High-Current ICL7660 Upgrade
- Inverts or Doubles Input Supply Voltage
- Selectable Oscillator Frequency: 10kHz/80kHz
- 88% Typ Conversion Efficiency at 100mA (IL to GND)
Applications
- Handheld Instruments (PDAs, Palmtops)
- Interface Power Supplies
- Laptop Computers
- Medical Instruments
- Operational Amplifier Power Supplies