The LM2660 CMOS charge-pump voltage converter is a versatile unregulated switched capacitor inverter or doubler. Operating from a wide 1.5-V to 5.5-V supply voltage, the LM2660 uses two low-cost capacitors to provide 100 mA of output current without the cost, size and EMI related to inductor-based converters. With an operating current of only 120 µA and operating efficiency greater than 90% at most loads, the LM2660 provides ideal performance for battery-powered systems. LM2660 devices can be operated directly in parallel to lower output impedance, thus providing more current at a given voltage.
The FC (frequency control) pin selects between a nominal 10-kHz or 80-kHz oscillator frequency. The oscillator frequency can be lowered by adding an external capacitor to the OSC pin. Also, the OSC pin may be used to drive the LM2660 with an external clock up to 150 kHz. Through these methods, output ripple frequency and harmonics may be controlled.
Additionally, the LM2660 may be configured to divide a positive input voltage precisely in half. In this mode, input voltages as high as 11 V may be used.