FEATURES
Charge Pump in 5-Pin SOT-23A Package
>95% Voltage Conversion Efficiency
Voltage Inversion and/or Doubling
Low 50µA (TCM828) Quiescent Current
Operates from +1.5V to +5.5V
Up to 25mA Output Current
Only Two External Capacitors Required
APPLICATIONS
LCD Panel Bias
Cellular Phones
Pagers
PDAs, Portable Dataloggers
Battery-Powered Devices
GENERAL DESCRIPTION
The TCM828/829 are CMOS “charge-pump” voltage
converters in ultra-small 5-Pin SOT-23A packages. They
invert and/or double an input voltage which can range from
+1.5V to +5.5V. Conversion efficiency is typically >95%.
Switching frequency is 12kHz for the TCM828 and 35kHz for
the TCM829.
External component requirement is only two capacitors
(3.3µF nominal) for standard voltage inverter applications.
With a few additional components a positive doubler can
also be built. All other circuitry, including control, oscillator,
power MOSFETs are integrated on-chip. Supply current
is 50µA (TCM828) and 115µA (TCM829).
The TCM828 and TCM829 are available in a 5-Pin
SOT-23A surface mount package.
