19-0202; Rev 2; 11/96
5 V/1 2 V/1 5 V o r Ad ju s t a b le , High-Effic ie nc y,
Low I , Ste p-Up DC-DC Controlle rs
Q
0–MAX73
_______________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
♦ 90% Efficiency for 10mA to 1A Load Currents
♦ Up to 15W Output Power
The MAX770–MAX773 step-up switching controllers pro-
vid e 90% e ffic ie nc y ove r a 10mA to 1A loa d . A
unique current-limited pulse-frequency-modulation (PFM)
control scheme gives these devices the benefits of
pulse-width-modulation (PWM) converters (high efficiency
at heavy loads), while using less than 110µA of supply
current (vs. 2mA to 10mA for PWM converters).
♦ 110µA Max Supply Current
♦ 5µA Max Shutdown Current
♦ 2V to 16.5V Input Range
These ICs use tiny external components. Their high
switching frequencies (up to 300kHz) allow surface-
mount magnetics of 5mm height and 9mm diameter.
(MAX770/MAX771/MAX772)
♦ Internal Shunt Regulator for High Input Voltages
(MAX773)
The MAX770/MAX771/MAX772 accept input voltages
from 2V to 16.5V. Output voltages are preset at 5V,
(MAX770), 12V (MAX771), and 15V (MAX772); they can
also be adjusted using two resistors.
♦ Preset or Adjustable Output Voltages
MAX770: 5V or Adjustable
MAX771: 12V or Adjustable
The MAX773 accepts inputs from 3V to 16.5V. For a wider
input range, it features an internal shunt regulator that
allows unlimited higher input voltages. The MAX773’s out-
put can be set to 5V, 12V, or 15V, or it can be adjusted
with two resistors.
MAX772: 15V or Adjustable
MAX773: 5V, 12V, 15V, or Adjustable
♦ Current-Limited PFM Control Scheme
♦ 300kHz Switching Frequency
The MAX770–MAX773 drive external N-channel MOSFET
switches, allowing them to power loads up to 15W. If less
p owe r is re q uire d , us e the MAX756/MAX757 or
MAX761/MAX762 step-up switching regulators with on-
board MOSFETs.
______________Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
PIN-PACKAGE
Plastic DIP
8 SO
MAX770CPA
MAX770CSA
MAX770C/D
MAX770EPA
MAX770ESA
MAX770MJA
0°C to +70°C
________________________Ap p lic a t io n s
0°C to +70°C
Dice*
Palmtops/Handy-Terminals
High-Efficiency DC-DC Converters
Battery-Powered Applications
Positive LCD-Bias Generators
Portable Communicators
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
8 Plastic DIP
8 SO
8 CERDIP**
Ordering Information continued at end of data sheet.
*Contact factory for dice specifications.
**Contact factory for availability and processing to MIL-STD-883B.
Flash Memory Programmers
_________________P in Co n fig u ra t io n s
__________Typ ic a l Op e ra t in g Circ u it
TOP VIEW
INPUT
2V TO V
OUT
1
2
3
4
8
7
6
5
EXT
V+
CS
OUTPUT
12V
GND
AGND
MAX770
MAX771
MAX772
N
EXT
CS
MAX771
SHDN
FB
ON/OFF
REF
SHDN
REF
DIP/SO
V+
FB AGND GND
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.