_______________General Description
The MAX761/MAX762 step-up switching regulators
provide high efficiency over a wide range of load currents,
delivering up to 150mA. A unique, current-limited
pulse-frequency-modulated (PFM) control scheme gives
the devices the benefits of pulse-width-modulated (PWM)
converters (high efficiency with heavy loads), while using
less than 110µA of supply current (vs. 2mA to 10mA for
PWM converters). The result is high efficiency over a wide
range of loads.
The MAX761/MAX762 input voltage range is 2V to 16.5V.
Output voltages are preset to 12V (MAX761) and 15V
(MAX762), or they can be set with two external resistors.
With a 5V input, the MAX761 guarantees a 12V, 150mA
output. Its high efficiency, low supply current, fast start-up
time, SHDN controlling capability, and small size make the
MAX761 ideal for powering flash memory.
The MAX761/MAX762 have an internal 1A power MOS-
FET, making them ideal for minimum-component, low- and
medium-power applications. These devices use tiny exter-
nal components, and their high switching frequencies (up
to 300kHz) allow for small surface-mount magnetics.
For increased output drive capability or higher output volt-
ages, use the MAX770–MAX773, which are similar in
design to the MAX761/MAX762, but drive external power
MOSFETs. For stepping up to 5V, see the MAX756/
MAX757 and MAX856-MAX859 data sheets.
_________________________Applications
Flash Memory Programming
PCMCIA Cards
Battery-Powered Applications
High-Efficiency DC-DC Converters
____________________________Features
♦ High Efficiency for a Wide Range of Load Currents
♦ 12V/150mA Flash Memory Programming Supply
♦ 110µA Max Supply Current
♦ 5µA Max Shutdown Supply Current
♦ 2V to 16.5V Input Voltage Range
♦ 12V (MAX761), 15V (MAX762) or Adjustable Output
♦ Current-Limited PFM Control Scheme
♦ 300kHz Switching Frequency
♦ Internal, 1A, N-Channel Power FET
♦ LBI/LBO Low-Battery Comparator
______________Ordering Information
MAX761/MAX762
12V/15V or Adjustable, High-Efficiency,
Low I
Q
, Step-Up DC-DC Converters
________________________________________________________________
Maxim Integrated Products
1
1
2
3
4
8
7
6
5
V+
LX
GND
REF
SHDN
FB
LBI
LBO
MAX761
MAX762
DIP/SO
TOP VIEW
__________________Pin Configuration
MAX761
LBI
SHDN
V+
FB
REF
LX
OUTPUT
12V
150mA
LOW-BATTERY
DETECTOR OUTPUT
LOW-BATTERY
DETECTOR INPUT
INPUT
4.75V
TO 12V
ON/OFF
GND
LBO
33µF
33µF
18µH
__________Typical Operating Circuit
Call toll free 1-800-998-8800 for free samples or literature.
19-0201; Rev 0; 11/93
PART TEMP. RANGE PIN-PACKAGE
MAX761CPA
0°C to +70°C 8 Plastic DIP
MAX761CSA 0°C to +70°C 8 SO
MAX761C/D 0°C to +70°C Dice*
MAX761ESA -40°C to +85°C 8 SO
MAX761EPA -40°C to +85°C 8 Plastic DIP
MAX761MJA -55°C to +125°C 8 CERDIP**
MAX762CPA
0°C to +70°C 8 Plastic DIP
MAX762CSA 0°C to +70°C 8 SO
MAX762C/D 0°C to +70°C Dice*
MAX762EPA -40°C to +85°C 8 Plastic DIP
MAX762ESA -40°C to +85°C 8 SO
MAX762MJA -55°C to +125°C 8 CERDIP**
* Contact factory for dice specifications.
** Contact factory for availability and processing to MIL-STD-883.
Evaluation Kit
Available