ADM8660 CMOS Switched-Capacitor Voltage Converter w/ Low Power Shutdown Pin

The ADM660/ADM8660 is a charge-pump voltage converter that can be used to either invert the input supply voltage giving VOUT = -VIN or double it (ADM660 only) giving VOUT = 2 x VIN. Input voltages ranging from +1.5 V to +7 V can be inverted into a negative -1.5 V to -7 V output supply. This inverting scheme is ideal for generating a negative rail in single power supply systems. Only two small external capacitors are needed for the charge pump. Output currents up to 50 mA with greater than 90% efficiency are achievable, while 100 mA achieves greater than 80% efficiency.

A Frequency Control (FC) input pin is used to select either 25 kHz or 120 kHz charge-pump operation. This is used to optimize capacitor size and quiescent current. With 25 kHz selected, a 10 µF external capacitor is suitable, while with 120 kHz the capacitor may be reduced to 2.2 µF. The oscillator frequency on the ADM660 can also be controlled with an external capacitor connected to the OSC input or by driving this input with an external clock. In applications where a higher supply voltage is desired it is possible to use the ADM660 to double the input voltage. With input voltages from 2.5 V to 7 V, output voltages from 5 V to 14 V are achievable with up to 100 mA output current.

The ADM8660 features a low power shutdown (SD) pin instead of the external oscillator (OSC) pin. This can be used to disable the device and reduce the quiescent current to 300 nA.

Features and Benefits
  • ADM660: Inverts or Doubles Input Supply Voltage
  • ADM8660: Inverts Input Supply Voltage
  • 100 mA Output Current
  • Shutdown Function (ADM8660)
  • 2.2 µF or 10 µF Capacitors
  • 0.3 V Drop at 30 mA Load
  • +1.5 V to +7 V Supply
  • Low Power CMOS: 600 µA Quiescent Current
  • Selectable Charge Pump Frequency (25 kHz/120 kHz)
  • Pin Compatible Upgrade for MAX660, MAX665, ICL7660
  • Available in 16-Lead TSSOP Package
Power Management
Data Sheets
Documentnote
ADM660/ADM8660: CMOS Switched-Capacitor Voltage Converters Data Sheet (Rev. C)PDF 282 kB
Order Information
Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
ADM8660ANZ Production8 ld PDIPOTH 50-40 to 85C2.021.92Y
ADM8660ARZ Production8 ld SOICOTH 98-40 to 85C2.021.92Y
Reference Materials
ADM660/ADM8660: CMOS Switched-Capacitor Voltage Converters Data Sheet (Rev. C) adm660
Charge Pumps Products (March 2003) adm660