TC3682_05 Datasheet, PDF (1/10 Pages) Microchip Technology – Inverting Charge Pump Voltage Doublers with Active Low Shutdown

Obsolete Device
TC3682/TC3683/TC3684
Inverting Charge Pump Voltage Doublers with Active Low Shutdown
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 TC3682
- 225μA (typ) for TC3683
- 700μA (typ) for TC3684
• Fully Compatible with 1.8V Logic Systems
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
TC3682EUA 8-Pin MSOP 12 -40°C to +85°C
TC3683EUA 8-Pin MSOP 35 -40°C to +85°C
TC3684EUA 8-Pin MSOP 125 -40°C to +85°C
Package Type
8-Pin MSOP
C1– 1
C2+ 2
C2– 3
V_{OUT 4}
TC3682
TC3683
TC3684
8 SHDN
7 C1+
6 V_IN
5 GND
General Description
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.
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).
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.
Functional Block Diagram
+
C1+
V_IN
C1
C1–
SHDN
C2+ TC3682
+
TC3683
C2
C2– ^TC3684
Input
ON
OFF
GND
V_OUT
V_OUT = -(2 x V_IN)
– _COUT
+
C1 must have a voltage rating ≥ V_IN
C2 and C_OUT must have a voltage rating ≥ 2V_IN
© 2005 Microchip Technology Inc.
DS21556C-page 1