© 2005 Microchip Technology Inc.

DS21537C-page 1

TC1682/TC1683/TC1684

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

-95

μA (typ) for TC1682

-225

μA (typ) for TC1683

-700

μA (typ) for TC1684

• 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

Package Type

General Description

The TC1682/TC1683/TC1684 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 TC1682, 35kHz for the

TC1683, and 125kHz for the TC1684. When the SHDN

pin is held at a logic high, the device goes into a very

low power mode of operation consuming less than 1

μA

(typ) of supply current.

Low output source impedance (typically

120

Ω),

provides output current up to 10mA. The TC1682/

TC1683/TC1684 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

products useful for a wide variety of negative bias

power supply applications.

Functional Block Diagram

Part

Number

Package

Osc.

Freq.

(kHz)

Operating

Temp.

Range

TC1682EUA

8-Pin MSOP

12

-40°C to +85°C

TC1683EUA

8-Pin MSOP

35

-40°C to +85°C

TC1684EUA

8-Pin MSOP

125

-40°C to +85°C

1

2

3

4

8

7

6

5

TC1682

TC1683

TC1684

SHDN

C2–

GND

C1–

C1+

C2+

8-Pin MSOP

C1+

C2+

C1–

C2

C2–

C1

TC1682

TC1683

TC1684

+

+

+

– C

OUT

Input

GND

C1 must have a voltage rating

SHDN

ON

OFF

Inverting Charge Pump Voltage Doublers with Active High Shutdown

Obsolete Device