________________General Description

The MAX680/MAX681 are monolithic, CMOS, dual

charge-pump voltage converters that provide ±10V out-

puts from a +5V input voltage. The MAX680/MAX681 pro-

vide both a positive step-up charge pump to develop

+10V from +5V input and an inverting charge pump to

generate the -10V output. Both parts have an on-chip,

8kHz oscillator. The MAX681 has the capacitors internal to

the package, and the MAX680 requires four external

capacitors to produce both positive and negative voltages

from a single supply.

The output source impedances are typically 150

Ω, pro-

viding useful output currents up to 10mA. The low quies-

cent current and high efficiency make this device suitable

for a variety of applications that need both positive and

negative voltages generated from a single supply.

The MAX864/MAX865 are also recommended for new

designs. The MAX864 operates at up to 200kHz and uses

smaller capacitors. The MAX865 comes in the smaller

µMAX package.

________________________Applications

The MAX680/MAX681 can be used wherever a single

positive supply is available and where positive and nega-

tive voltages are required. Common applications include

generating ±6V from a 3V battery and generating ±10V

from the standard +5V logic supply (for use with analog

circuitry). Typical applications include:

____________________________Features

o 95% Voltage-Conversion Efficiency

o 85% Power-Conversion Efficiency

o +2V to +6V Voltage Range

o Only Four External Capacitors Required (MAX680)

o No Capacitors Required (MAX681)

o 500µA Supply Current

o Monolithic CMOS Design

+5V to ±10V Voltage Converters

________________________________________________________________

Maxim Integrated Products

1

C2-

GND

V-

1

2

8

7

V+

C1+

C2+

C1-

MAX680

DIP/SO

TOP VIEW

3

4

6

5

14

13

12

11

10

9

8

1

2

3

4

5

6

7

C2+

C1-

C1-

V+

MAX681

V+

GND

GND

V-

C2-

C2-

DIP

_________Typical Operating Circuits

MAX680

+10V

4.7

µF

4.7

µF

4.7

µF

4.7

µF

-10V

GND

+10V

-10V

GND

FOUR PINS REQUIRED

(MAX681 ONLY)

+5V

GND

GND

+5V

C1-

C1+

V-

V+

C2-

GND

+5V to ±10V CONVERTER

MAX681

V-

V+

GND

C1+

_________________Pin Configurations

19-0896; Rev 1; 7/96

PART

MAX680CPA

MAX680CSA

MAX680C/D

0°C to +70°C

0°C to +70°C

0°C to +70°C

TEMP. RANGE

PIN-PACKAGE

8 Plastic DIP

8 Narrow SO

Dice

_______________Ordering Information

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800

MAX680EPA

MAX680ESA

-40°C to +85°C

-40°C to +85°C

8 Plastic DIP

8 Narrow SO

MAX680MJA

-55°C to +125°C

8 CERDIP

MAX681CPD

MAX681EPD

-40°C to +85°C

0°C to +70°C

14 Plastic DIP

14 Plastic DIP

±6V from 3V Lithium Cell

Hand-Held Instruments

Data-Acquisition Systems

Panel Meters

±10V from +5V Logic

Supply

Battery-Operated

Equipment

Operational Amplifier

Power Supplies