Document
ME 7660
ME7660 Charge Pump DC-DC Voltage Converter
Introduction Me7660 is a charge pump dc-to-dc voltage converter using AL-gate CMOS
technology and optimization design. It converters a +1.5V to +10V input to a corresponding -1.5V to -10V output using only two external capacitors, eliminating inductors and their associated cost, size and EMI. The on-board oscillator operates at a nominal frequency of 10KHZ. Operation below 10 KHZ (for lower supply current applications) is possible by connecting an external capacitor from OSC to ground. Features: ! Converts +5V Logic supply to + 5V ! Wide input voltage range: 1.5V~10V ! Efficient voltage conversion: 99.9% ! Good power efficiency: 98% ! Low power supply: 50uA @5Vin ! Easy to use: only two external capacitors required ! 8-pin DIP and 8-pin small outline packages are available ! Compatible with RS232 negative power supply standard ! High ESD protection: up to 3kV ! No Dx diode needed for high voltage operation Pin Configuration
Packages: 8-pin DIP and 8-pin SOIC
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ME 7660
Pin Description Pin No. Symbol
1 NC 2 CAP+ 3 GND 4 CAP5 Vout 6 Low Voltage 7 OSC 8 V+
Description No connection Connecting external capacitor (+) pin
Ground Pin Connecting external capacitor (-) pin
Voltage output pin Low voltage selection pin Connecting oscillation capacitor pin
Power supply pin
Functional Block Diagram
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Absolute Maximum Rating ! Supply Voltage: +10.5V ! LV and OSC Inputs Voltage: -0.3V (V++0.3V) for V+<5.5V
(V+-5.5V) (V++0.3V) for V+>5.5V
! Current Into LV: 20µA V+>3.5V
! Output Short Duration (Vsupply 5.5V):
! Power Dissipation TA 75
Plastic DIP
730mV
SOIC
470mV
ME 7660
Electrical Characteristics:(V+=5V,COSC=0) Test circuit is at page 5
Symbol Item Conditions Min Typ Max Unit
I+ V+H V+L ROUT
FOSC PEFF VOUTEFF
Supply Current Supply Voltage,
High Supply Voltage, Low Output Resistance
Oscillator Frequency
Power Efficiency
Voltage Conversion Efficiency
RL= LV Open
LV to GND
IOUT=20mA TA=25 IOUT=3mA V+=2V TA=25 Pin 7 open
RL=5k
RL=
— 60 3—
1.5 —
110 220
— 10 90 98 98 99 9
120 10 4
— — —
µA V V
kHz % %
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Typical Performance Characteristics
10000
Output Resistance vs.Supply Voltage
ME 7660
Output Resistance(Ohm)
1000
100
Output Load(Ohm)
10 0
1
130 120 110 100
90 80
0
234567 Supply Voltage(V)
Output Load vs. Load Current+(V+=+5V)
5 10 15 20 Load Current(mA)
8 25
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Output Voltage(V)
ME 7660
Output Voltage vs. Output Current (V+=+5V)
1
0
-1
-2
-3
-4
-5 0
5 10 15 20 25 30 Output Current (mA)
Power Conversion Efficiency vs.Load Current (V+=+5V)
100 90 80 70 60 50 40 30 20 10 0 5
10 15 20 Load Current (mA)
25
30
Power Conversion Efficiency(%)
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Testing Circuit
ME 7660
Detailed Description
ME7660 together with two external capacitors C1 C2 complement a voltage Inverter. Capacitor C1 is charged to a voltage V+, for the first half cycle when switches S1 and S3 are closed ( while switches S2 and S4 are open during this half cycle); During the second.