ZXCP330 Datasheet, PDF (1/9 Pages) Zetex Semiconductors – SWITCHED CAPACITOR DC-DC CONVERTER

SWITCHED CAPACITOR DC-DC CONVERTER
ZXCP330
DEVICE DESCRIPTION
The ZXCP330 is the first in a series of switched capacitor DC to DC converters,
converting an input voltage from between 2 volts and 4.4 volts to a regulated
output voltage of 3.3V with a maximum load current of 40mA. The device
operates with one flying capacitor and two small bypass capacitors at input
and output making for a very small solution. Very low quiescent current
makes these devices ideal for low power and battery powered applications.
Regulation is achieved by sensing the output and enabling the device charge pump when it falls below the sense
threshold. This technique leads to high efficiency conversion. The method is also efficient for low current loads.
Here the duty cycle will be low and the quiescent current drawn whilst the charge pump is disabled is very small.
The device includes a pin for logic controlled shutdown of the output, and also features thermal shutdown, which
protects against short circuit damage as well as excessive temperatures. The device is supplied in a 6 lead SOT-23
package.
Contact Zetex marketing for availability of other voltage options.
FEATURES
· Very low power: IQ = 20µA
APPLICATIONS
· Battery backup supplies
· Regulated output voltage: 3.3V, ± 4%
· Smart card readers
· Output current: 20mA at VIN = 2V
· Li-Ion battery backup supplies
· Output current: 40mA at VIN = 2.5V
· SIM interface supplies for cellular phones
· No inductors required
· Hand held computers
· Very low shutdown current: <1µA
· Short circuit and over-temp protected
· Very small package: SOT23-6 pin
APPLICATIONS DIAGRAM
PROVISIONAL ISSUE A - DECEMBER 2001
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