TC7660
Switched-capacitor voltage converter that inverts or doubles input voltage, converting +5V to -5V or +10V with few external components.
Product Overview
Description
The TC7660 is a charge pump voltage converter that can invert or double an input voltage using only two external capacitors. It converts a positive voltage in the +1.5V to +10V range to its negative equivalent (-1.5V to -10V).
The device operates by switching capacitors between series and parallel configurations, eliminating the need for inductors. This provides a compact, low-EMI solution for generating negative supply voltages.
With output currents up to 40mA and conversion efficiency of 99%, the TC7660 is ideal for generating negative rails for op amps, ADCs, and interface circuits in single-supply systems.
Product Series
TC
Primary Application
Negative supply generation
Key Features
- Voltage inversion or doubling
- No inductors is needed
- Low EMI
- High efficiency 99%
- Simple 2-capacitor design
- Low output resistance
Specifications
| Input Voltage | +1.5V to +10V |
|---|---|
| Output Voltage | -1.5V to -10V (inverted) |
| Output Current | 40mA max |
| Efficiency | 99% typical |
| Switching Frequency | 10kHz typical |
| External Components | 2 capacitors |
| Package | PDIP-8, SOIC-8 |
| Temperature Range | -40°C to +85°C |
| Architecture | Charge Pump |
Applications
Negative supply generation
Electronic system design
RS-232 interfaces
Communication and interface
Op amp power supplies
Electronic system design
ADC reference circuits
Data acquisition and conversion
Data acquisition systems
Data acquisition and conversion
FAE Expert Insights
"The TC7660 is the classic charge pump solution for generating negative voltages. When you need a simple -5V supply for op amps in a single-supply system, this is the easiest solution. No inductors means no EMI headaches and simple PCB layout. The efficiency is excellent for light loads. I use it regularly for RS-232 level shifters and bipolar op amp supplies."
Simple 2-capacitor solution for negative voltage generation without inductors
— Robert Kim, BeiLuo
Frequently Asked Questions
What capacitor values should I use with TC7660?
The TC7660 requires two capacitors: a pump capacitor (C1) between pins 2 and 4, and a reservoir capacitor (C2) at the output. Use 10μF electrolytic or ceramic capacitors for most applications. For higher output current, increase C2 to 47μF or 100μF. Use low-ESR capacitors for best performance. The capacitors should be rated for the full input/output voltage.
Use 10μF for standard applications; increase to 47-100μF for higher current.