SP682
Corporation
Micro Power Inverting Charge Pump
■
Low Power Voltage Conversion
■
+2.4V to +5.5V Input Range
■
99% Voltage Conversion Efficiency
■
Typical 60µA Supply Current
■
Requires Only Three External Capacitors
■
Includes Low Power Shutdown Option
■
Ideal in Portable Applications Such As
Handheld Instruments
Cellular Phones
Personal Digital Assistants
Laptops and Notebooks
■
Pin Compatible Upgrade to Microchip's
TC682
C1-
1
C2+
2
C2-
3
VOUT
4
8
SD
SP682
8 Pin MSOP
7
C1+
6
VCC
5
GND
APPLICATIONS
■
LCD Display
■
Negative bias supply for op amps
■
Serial interface protocol circuits
DESCRIPTION
The
SP682
is a monolithic charge pump voltage converter that produces a doubled, negative
voltage from a single positive supply. The
SP682
charge pump outputs a –10V voltage from
a +5V input. Three external charge pump capacitors are required to support the voltage
conversion and voltage doubling process. An internal oscillator generates a 12kHz clock
which cycles the internal switching that charges the storage and transfer capacitors. The
charge pump architecture is fabricated using a low power BiCMOS process technology.
The
SP682
charge pump is ideal for low power applications requiring a typical +3V battery
source such as a lithium cell. Typical applications are handheld instruments, notebook and
laptop computers, cellular phones, and data acquisition or GP systems. The
SP682
is
packaged in either 8-pin NSOIC, 8-pin MSOP for surface mount applications, and 8 Pin PDIP.
TYPICAL APPLICATION CIRCUIT
+2.4V to +5V
1µF
+
6
7
C1
1
2
C1–
C2+
C1+
V
CC
V
OUT
4
-
V
OUT
C
OUT
SP682
SD
GND
5
8
C2
3
C2–
Date: 5/20/04
SP682 Micro Power Inverting Charge Pump
© Copyright 2004 Sipex Corporation
1
SIPEX [ SIPEX CORPORATION ]
