TC1225 Datasheet, PDF (1/10 Pages) Microchip Technology – Inverting Dual (-VIN, -2VIN) Charge Pump Voltage Converters

TC1225
TC1226
TC1227
Inverting Dual (–V_IN, –2V_IN) Charge Pump Voltage Converters
FEATURES
s Small 8-Pin MSOP Package
s Operates from 1.8V to 5.5V
s Up to 5mA Output Current at –V_IN Pin
s Up to 1mA Output Current at –2V_IN Pin
s –V_IN and –2V_IN Outputs Available
s Low Supply Current
.......................................... 120µA (MAX) for TC1225
.......................................... 360µA (MAX) for TC1226
.......................................... 1.5mA (MAX) for TC1227
TYPICAL APPLICATIONS
s LCD Panel Bias
s Cellular Phones PA Bias
s Pagers
s PDAs, Portable Data loggers
s Battery Powered Devices
TYPICAL OPERATING CIRCUIT
+
C1+
C1
V_IN
INPUT
C1–
–V_IN
OUTPUT 1
C2+
– _COUT1
+
TC1225
+
C2
TC1226
C2– _TC1227
GND
–2 V_IN
OUTPUT 2
– _COUT2
+
Notes:
1) C1 and C_OUT1 must have a voltage rating greater
than or equal to V_IN
2) C2 and C_OUT2 must have a voltage rating greater
than or equal to 2V_IN
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 –V_IN output) and a negative doubling
voltage inversion (available at the –2 V_IN output), with a low
output impedance capable of providing output currents up to
5mA for the –V_IN output and 1mA for the –2V_IN 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
TC1226EUA 8-Pin MSOP
35
TC1227EUA 8-Pin MSOP
125
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
PIN CONFIGURATION
8-Pin MSOP
C1– 1
C2+ ²
C2– 3
–2V_{IN 4}
TC1225
TC1226
TC1227
8 ^–VIN
7 ^C1+
6 ^V_IN
5 GND
© 2001 Microchip Technology Inc. DS21369A
TC1225/6/7-1 3/24/00