19-0176; Rev 0; 6/94
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-5V/-12V/-15V or Adjustable,
High-Efficiency, Low IQ DC-DC Inverters
____________________________Features
o High Efficiency for a Wide Range of Load Currents
________________________Applications
LCD-Bias Generators
Portable Instruments
LAN Adapters
Remote Data-Acquisition Systems
Battery-Powered Applications
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
PART
TEMP. RANGE
PIN-PACKAGE
MAX764CPA
0°C to +70°C
8 Plastic DIP
MAX764CSA
MAX764C/D
MAX764EPA
MAX764ESA
MAX764MJA
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
8 SO
Dice*
8 Plastic DIP
8 SO
8 CERDIP**
MAX765CPA
0°C to +70°C
8 Plastic DIP
MAX765CSA
MAX765C/D
MAX765EPA
MAX765ESA
MAX765MJA
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
8 SO
Dice*
8 Plastic DIP
8 SO
8 CERDIP**
Ordering Information continued on last page.
* Dice are tested at TA = +25°C, DC parameters only.
**Contact factory for availability and processing to MIL-STD-883.
__________Typical Operating Circuit
INPUT
3V TO 15V
__________________Pin Configuration
TOP VIEW
V+
OUTPUT
-5V
LX
ON/OFF
47µH
SHDN
OUT
1
8
LX
FB
MAX764
2
7
V+
6
V+
5
GND
SHDN 3
REF 4
MAX764
MAX765
MAX766
OUT
REF
FB
GND
DIP/SO
________________________________________________________________ Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
1
MAX764/MAX765/MAX766
_______________General Description
The MAX764/MAX765/MAX766 inverting switching regulators are highly efficient over a wide range of load currents, delivering up to 1.5W. A unique, current-limited,
pulse-frequency-modulated (PFM) control scheme combines 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 voltage is preset at -5V (MAX764), -12V (MAX765), or -15V
(MAX766); it can also be adjusted from -1V to -16V
using two external resistors (Dual ModeTM). The maximum operating VIN - VOUT differential is 20V.
These devices use miniature external components; their
high switching frequencies (up to 300kHz) allow for less
than 5mm diameter surface-mount magnetics. A standard 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.