The LM2660/LM2661 CMOS charge-pump voltage converter inverts a positive voltage in the range of 1.5V to 5.5V to the corresponding negative voltage. The LM2660/LM2661 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 A and operating efficiency greater than 90% at most loads, the LM2660/LM2661 provides ideal performance for battery powered systems. The LM2660/LM2661 may also be used as a positive voltage doubler. 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/LM2661 with an external clock. For LM2660, a frequency control (FC) pin selects the oscillator frequency of 10 kHz or 80 kHz. For LM2661, an external shutdown (SD) pin replaces the FC pin. The SD pin can be used to disable the device and reduce the quiescent current to 0.5 A. The oscillator frequency for the LM2661 is 80 kHz.