General Description

The ultra-small MAX828/MAX829 monolithic, CMOS

charge-pump inverters accept input voltages ranging

from +1.5V to +5.5V. The MAX828 operates at 12kHz,

and the MAX829 operates at 35kHz. Their high efficiency

(greater than 90% over most of the load-current range)

and low operating current (60µA for the MAX828) make

these devices ideal for both battery-powered and board-

level voltage-conversion applications.

The MAX828/MAX829 combine low quiescent current

and high efficiency. Oscillator control circuitry and four

power MOSFET switches are included on-chip.

Applications include generating a -5V supply from a +5V

logic supply to power analog circuitry. Both parts come

in a 5-pin SOT23-5 package and can deliver 25mA with

a voltage drop of 500mV.

For a similar device with logic-controlled shutdown,

refer to the MAX1719/MAX1720/MAX1721. For applica-

tions requiring more power, the MAX860 delivers up to

50mA with a voltage drop of 600mV, in a space-saving

µMAX package.

Applications

Small LCD Panels

Cell Phones

Medical Instruments

Handy-Terminals, PDAs

Battery-Operated Equipment

Features

o 5-Pin SOT23-5 Package

o 95% Voltage Conversion Efficiency

o Inverts Input Supply Voltage

o 60µA Quiescent Current (MAX828)

o +1.5V to +5.5V Input Voltage Range

o Requires Only Two Capacitors

o 25mA Output Current

Switched-Capacitor Voltage Inverters

________________________________________________________________ Maxim Integrated Products

1

TOP VIEW

IN

GND

C1-

C1+

OUT

SOT23-5

1

5

MAX828

MAX829

2

3

4

Pin Configuration

NEGATIVE VOLTAGE CONVERTER

C1+

C1-

IN

OUT

GND

INPUT

SUPPLY

VOLTAGE

NEGATIVE

OUTPUT

VOLTAGE

MAX828

MAX829

4

3

52

1

Typical Operating Circuit

19-0495; Rev 3; 9/99

PART

MAX828EUK

-40°C to +85°C

TEMP. RANGE

PIN-

PACKAGE

5 SOT23-5

Ordering Information

MAX829EUK

-40°C to +85°C

5 SOT23-5

SOT

TOP MARK

AABI

AABJ

For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.