TC3682/TC3683/TC3684
M
Inverting Charge Pump Voltage Doublers with Active Low Shutdown
Features
General Description
• 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
The TC3682/TC3683/TC3684 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 TC3682, 35kHz for the
TC3683, and 125kHz for the TC3684. When the SHDN
pin is held at a logic low, the device goes into a very low
power mode of operation consuming less than 1µA
(typ) of supply current.
- 95µA (typ) for TC3682
- 225µA (typ) for TC3683
Low output source impedance (typically 120Ω), pro-
vides output current up to 10mA. The TC3682/TC3683/
TC3684 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).
- 700µA (typ) for TC3684
• Fully Compatible with 1.8V Logic Systems
Applications
• LCD Panel Bias
• Cellular Phones PA Bias
• Pagers
The minimum external part count, small physical size
and shutdown mode feature make this family of prod-
ucts useful for a wide variety of negative bias power
supply applications.
• PDAs, Portable Data Loggers
• Battery-Powered Devices
Device Selection Table
Functional Block Diagram
Osc.
Freq.
(kHz)
Operating
Temp.
Range
Part
Number
Package
C1+
V
+
IN
Input
ON
C1
TC3682EUA 8-Pin MSOP
TC3683EUA 8-Pin MSOP
12
35
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
C1–
SHDN
OFF
C2+ TC3682
TC3684EUA 8-Pin MSOP 125
+
C2
TC3683
TC3684
C2–
Package Type
V
= -(2 x V )
IN
OUT
GND
8-Pin MSOP
V
OUT
–
C
OUT
1
2
3
4
8
7
6
5
SHDN
+
C2+
OUT
C1+
TC3682
TC3683
TC3684
C1 must have a voltage rating ≥ V
IN
V
IN
C2 and C
must have a voltage rating ≥ 2V
OUT
IN
V
GND
2002 Microchip Technology Inc.
DS21556B-page 1