_______________General Description

The MAX764/MAX765/MAX766 inverting switching regu-

lators are highly efficient over a wide range of load cur-

rents, delivering up to 1.5W. A unique, current-limited,

pulse-frequency-modulated (PFM) control scheme com-

bines the benefits of traditional PFM converters with the

benefits of pulse-width-modulated (PWM) converters.

Like PWM converters, the MAX764/MAX765/MAX766 are

highly efficient at heavy loads. Yet because they are PFM

devices, they use less than 120µA of supply current (vs.

2mA to 10mA for a PWM device).

The input voltage range is 3V to 16V. The output volt-

age is preset at -5V (MAX764), -12V (MAX765), or -15V

(MAX766); it can also be adjusted from -1V to -16V

These devices use miniature external components; their

high switching frequencies (up to 300kHz) allow for less

than 5mm diameter surface-mount magnetics. A stan-

dard 47µH inductor is ideal for most applications, so no

magnetics design is necessary.

An internal power MOSFET makes the MAX764/MAX765/

MAX766 ideal for minimum component count, low- and

medium-power applications. For increased output drive

capability or higher output voltages, use the

MAX774/MAX775/MAX776 or MAX1774, which drive an

external power P-channel MOSFET for loads up to 5W.

________________________Applications

LCD-Bias Generators

Portable Instruments

LAN Adapters

Remote Data-Acquisition Systems

Battery-Powered Applications

____________________________Features

o High Efficiency for a Wide Range of Load Currents

o 250mA Output Current

o 120µA Max Supply Current

o 5µA Max Shutdown Current

o 3V to 16V Input Voltage Range

o -5V (MAX764), -12V (MAX765), -15V (MAX766),

or Adjustable Output from -1V to -16V

o Current-Limited PFM Control Scheme

o 300kHz Switching Frequency

o Internal, P-Channel Power MOSFET

______________Ordering Information

Ordering Information continued on last page.

**Contact factory for availability and processing to MIL-STD-883.

-5V/-12V/-15V or Adjustable,

________________________________________________________________

Maxim Integrated Products

1

1

2

3

4

8

7

6

5

LX

V+

V+

GND

REF

SHDN

FB

OUT

MAX764

MAX765

MAX766

DIP/SO

TOP VIEW

__________________Pin Configuration

GND

MAX764

SHDN

LX

OUT

ON/OFF

REF

47µH

OUTPUT

-5V

INPUT

3V TO 15V

V+

FB

__________Typical Operating Circuit

Call toll free 1-800-998-8800 for free samples or literature.

19-0176; Rev 0; 6/94

PART

MAX764CPA

MAX764CSA

MAX764C/D

0°C to +70°C

0°C to +70°C

0°C to +70°C

TEMP. RANGE

PIN-PACKAGE

8 Plastic DIP

8 SO

Dice*

MAX764EPA

MAX764ESA

-40°C to +85°C

-40°C to +85°C

8 Plastic DIP

8 SO

MAX764MJA

-55°C to +125°C

8 CERDIP**

MAX765CPA

MAX765CSA

MAX765C/D

0°C to +70°C

0°C to +70°C

0°C to +70°C

8 Plastic DIP

8 SO

Dice*

MAX765EPA

MAX765ESA

-40°C to +85°C

-40°C to +85°C

8 Plastic DIP

8 SO

MAX765MJA

-55°C to +125°C

8 CERDIP**

Evaluation

Kit

Available