TC2682 Datasheet, PDF (1/10 Pages) Microchip Technology – Inverting Charge Pump Voltage Doublers

M ^{TC2682/TC2683/TC2684}
Inverting Charge Pump Voltage Doublers
Features
• Small 8-Pin MSOP Package
• Operates from 1.8V to 5.5V
• 120 Ohms (typ) Output Resistance
• 99% Voltage Conversion Efficiency
• Only 3 External Capacitors Required
• Power-Saving Shutdown Mode
• Low Active Supply Current
- 95µA (typ) for TC2682
- 225µA (typ) for TC2683
- 700µA (typ) for TC2684
Applications
• LCD Panel Bias
• Cellular Phones PA Bias
• Pagers
• PDAs, Portable Data Loggers
• Battery-Powered Devices
Device Selection Table
Part
Number
Package
Osc.
Freq.
(kHz)
Operating
Temp.
Range
TC2682EUA 8-Pin MSOP 12 -40°C to +85°C
TC2683EUA 8-Pin MSOP 35 -40°C to +85°C
TC2684EUA 8-Pin MSOP 125 -40°C to +85°C
Package Type
8-Pin MSOP
C1– 1
C2+ 2
C2– 3
V_{OUT 4}
TC2682
TC2683
TC2684
8 NC
7 C1+
6 V_IN
5 GND
General Description
The TC2682/TC2683/TC2684 are CMOS charge pump
converters that provide an inverted doubled output
from a single positive supply. An on-board oscillator
provides the clock and only three external capacitors
are required for full circuit implementation. Switching
frequencies are 12kHz for the TC2682, 35kHz for the
TC2683, and 125kHz for the TC2684.
Low output source impedance (typically 120Ω),
provides output current up to 10mA. The TC2682/
TC2683/TC2684 feature a 1.8V to 5.5V operating
voltage range and high efficiency, which make them an
ideal choice for a wide variety of applications requiring
a negative doubled voltage derived from a single
positive supply (for example: generation of -7.2V from
a +3.6V lithium cell or -10V generated from a +5V logic
supply).
The minimum external part count and small physical
size make this family of products useful for a wide
variety of negative bias power supply applications.
Functional Block Diagram
+
C1+
C1
C1–
V_IN
Input
C2+ TC2682
+
TC2683
C2
C2– ^TC2684
GND
V_OUT
V_OUT = -(2 x V_IN)
– _COUT
+
C1 must have a voltage rating ≥ VIN
C2 and C_OUT must have a voltage rating ≥ 2V_IN
 2002 Microchip Technology Inc.
DS21548B-page 1