Obsolete Device
TCM680
+5V To ±10V Voltage Converter
Features
• 99% Voltage Conversion Efficiency
• 85% Power Conversion Efficiency
• Input Voltage Range:
- +2.0V to +5.5V
• Only 4 External Capacitors Required
• 8-Pin SOIC Package
General Description
The TCM680 is a dual charge pump, voltage converter
that produces output voltages of +2V
IN
and -2V
IN
from
a single input voltage of +2.0V to +5.5V. Common
applications include ±10V from a single +5V logic
supply and ±6V from a +3V lithium battery.
The TCM680 is packaged in 8-pin SOIC and PDIP
packages and requires only four inexpensive, external
capacitors. The charge pumps are clocked by an on-
board 8 kHz oscillator. Low output source impedances
(typically 140
Ω)
provide maximum output currents of
10 mA for each output. Typical power conversion effi-
ciency is 85%.
High efficiency, small size and low cost make the
TCM680 suitable for a wide variety of applications that
need both positive and negative power supplies
derived from a single input voltage.
Applications
•
•
•
•
•
•
•
±10V From +5V Logic Supply
±6V From a 3V Lithium Cell
Handheld Instruments
Portable Cellular Phones
LCD Display Bias Generator
Panel Meters
Operational Amplifier Power Supplies
Package Type
PDIP
Typical Operating Circuit
+5V
C
1
+
4.7 µF
C
1+
C
1-
C
2+
C
2-
GND
V
OUT-
GND
V
OUT-
= -(2 x V
IN
)
C
3
4.7 µF
+
V
IN
V
OUT+
C
4
+ 4.7 µF
V
OUT+
= (2 x V
IN
)
C
1 -
C
2+
C
2 -
V
OUT-
1
2
8 V
OUT+
7 C
1 +
TCM680CPA
3
TCM680EPA
6 V
IN
4
5 GND
TCM680
C
2
+
4.7 µF
SOIC
GND
C
1 -
C
2+
C
2 -
V
OUT-
1
2
8 V
OUT+
7 C
1 +
TCM680COA
3
TCM680EOA
6 V
IN
4
5 GND
©
2005 Microchip Technology Inc.
DS21486C-page 1
MICROCHIP [ MICROCHIP TECHNOLOGY ]
