
TC1225/6/7-1
3/24/00
TC1225
TC1226
TC1227
2001 Microchip Technology Inc.
DS21369A
Inverting Dual (–VIN, –2VIN) Charge Pump Voltage Converters
FEATURES
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Small 8-Pin MSOP Package
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Operates from 1.8V to 5.5V
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Up to 5mA Output Current at –VIN Pin
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Up to 1mA Output Current at –2VIN Pin
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–VIN and –2VIN Outputs Available
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Low Supply Current
.......................................... 120
A (MAX) for TC1225
.......................................... 360
A (MAX) for TC1226
.......................................... 1.5mA (MAX) for TC1227
TYPICAL APPLICATIONS
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LCD Panel Bias
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Cellular Phones PA Bias
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Pagers
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PDAs, Portable Data loggers
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Battery Powered Devices
GENERAL DESCRIPTION
The TC1225/1226/1227 are CMOS dual inverting charge
pump voltage converters in 8-Pin MSOP packages. An on-
board oscillator provides the clock, and only four external
capacitors are required for full circuit implementation. Switch-
ing frequencies are 12kHz for the TC1225, 35kHz for the
TC1226, and 125kHz for the TC1227.
These devices provide both a negative voltage inversion
(available at the –VIN output) and a negative doubling
voltage inversion (available at the –2 VIN output), with a low
output impedance capable of providing output currents up to
5mA for the –VIN output and 1mA for the –2VIN output. The
input voltage can range from +1.8V to +5.5V.
ORDERING INFORMATION
Part No.
Package Osc Freq (kHz) Temp Range
TC1225EUA
8-Pin MSOP
12
–40
°C to +85°C
TC1226EUA
8-Pin MSOP
35
–40
°C to +85°C
TC1227EUA
8-Pin MSOP
125
–40
°C to +85°C
TYPICAL OPERATING CIRCUIT
C1+
C2+
VIN
–VIN
C1–
C2
C2–
C1
TC1225
TC1226
TC1227
COUT1
–2 VIN
+
–
+
– COUT2
OUTPUT 1
OUTPUT 2
INPUT
GND
PIN CONFIGURATION
1
2
3
4
8
7
6
5
TC1225
TC1226
TC1227
–2VIN
–VIN
VIN
C2–
GND
C1–
C1+
C2+
8-Pin MSOP
Notes:
1) C1 and COUT1 must have a voltage rating greater
than or equal to VIN
2) C2 and COUT2 must have a voltage rating greater
than or equal to 2VIN