GS7660 Datasheet, PDF (1/9 Pages) Vishay Siliconix – Switched-Capacitor Voltage Converter

GS7660
New Product
Vishay
formerly General Semiconductor
Switched-Capacitor Voltage Converter
8 Pin Dip
SO-8
Features
• Low output impedance ( typical 35Ω at VIN = 5V )
• Low quiescent current ( typical 36µA at VIN = 5V)
• High power conversion efficiency ( typical 98% )
• Simple and accurate voltage conversion from
positive to negative polarities
• Improved latch-up protection
• No external diodes required
Applications
• – 5V supply from + 5V logic supply
• EIA/TIA – 232E and EIA/TIA – 562 power supplies
• Portable telephones
• Data acquisition systems
• Personal communications equipment
• Panel meters
• Handheld instruments
Description
The GS7660 is a monolithic CMOS switched capacitor
voltage converter, designed to be an improved direct
replacement of the popular ICL7660, MAX1044 and
LTC1044. They perform supply voltage conversions from
positive to negative for an input voltage range of +1.5V to
+6.0V to their negative complements of –1.5V to –6.0V.
The input voltage can also be doubled (VOUT = 2VIN),
halved (VOUT = VIN/2), or multiplied (VOUT = ± n.VIN).
Contained on the chip are a series Power Supply regula-
tor, Oscillator, control Circuitry and four Power MOS
Switches. The oscillator, when unloaded, oscillates at a
nominal frequency of 10 kHz, with an Input voltage of 5.0V.
This frequency can be lowered by the addition of an external
capacitor to the “Osc” terminal or overdriven by an external
frequency source.
An Oscillator “boost” function is available to increase the
oscillator frequency which will optimize performance of
certain parameters. The Lv input can be connected to
ground to improve low voltage operation (VIN ≤ 3V), or left
open for input voltages greater than 3V to reduce power
dissipation.
The GS7660 provides superior performance over earlier
designs by combining low output impedance and low qui-
escent current with high efficiency and by eliminating diode
voltage drop losses. The only external components
required are two low cost electrolytic capacitors.
Typical Application Circuit
VIN (1.5V to 6V)
10µF ⁺
C1
1
5
2
6
GS7660
3
7
Required for
VIN 3V
4
8
VOUT = --VIN
10µF
+ C2
Negative Voltage Converter
Document Number 74819
24-May-02
www.vishay.com
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