19-0195; Rev 0; 10/93
Adjustable, Step-Down,
Current-Mode PWM Regulators
________________________Applications
Cellular Phones & Radios
Portable Communications Equipment
Portable Instruments
____________________________Features
o
o
o
o
o
o
o
o
o
o
Up to 750mA Load Currents
160kHz High-Frequency, Current-Mode PWM
85% to 96% Efficiencies
33µH or 100µH Pre-Selected Inductor Value,
No Component Design Required
1.7mA Quiescent Supply Current
6µA Shutdown Supply Current
Adjustable Output Voltage
Overcurrent, Soft-Start, and Undervoltage
Lockout Protection
Cycle-by-Cycle Current Limiting
8-Pin DIP/SO Packages (MAX750A)
______________Ordering Information
PART
TEMP. RANGE
MAX750ACPA
0°C to +70°C
8 Plastic DIP
PIN-PACKAGE
MAX750ACSA
MAX750AC/D
MAX750AEPA
MAX750AESA
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
8 SO
Dice*
8 Plastic DIP
8 SO
MAX750AMJA
-55°C to +125°C
8 CERDIP**
Ordering Information continued on last page.
* Contact factory for dice specifications.
**Contact factory for availability and processing to MIL-STD-883.
Computer Peripherals
_________________Pin Configurations
__________Typical Operating Circuit
INPUT
4V TO 16V
TOP VIEW
SHDN
1
8
V+
REF
2
7
LX
6
GND
5
OUTPUT ADJ.
FROM
VREF TO V+
I.C.
SS 3
MAX750A
MAX758A
CC 4
V+
MAX750A
MAX758A
DIP
ON/OFF
SHDN
REF
8
MAX750A
CC 4
LX
6
I.C.
CC
GND
5
2
SS 3
SHDN
V+
7
1
33µH
LX
REF
SS
GND
SO
Pin Configurations continued on last page.
________________________________________________________________ Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
1
MAX750A/MAX758A
_______________General Description
The MAX750A/MAX758A are adjustable-output, CMOS,
step-down, DC-DC switching regulators. The
MAX758A accepts inputs from 4V to 16V and delivers
750mA, while the MAX750A accepts inputs from 4V to
11V and delivers 450mA. Typical efficiencies are 85%
to 90%. Typical quiescent current is 1.7mA, or only
6µA in shutdown mode. The output does not exhibit
any ripple at subharmonics of the switching frequency
over its specified range.
Pulse-width-modulation (PWM) current-mode control
provides precise output regulation and excellent transient responses. Output voltage accuracy is guaranteed to be ±4.5% plus feedback-resistor tolerance over
line, load, and temperature variations. Fixed-frequency
switching and absence of subharmonic ripple allows
easy filtering of output ripple and noise, as well as the
use of small external components. These regulators
require only a single inductor value to work in most
applications, so no inductor design is necessary.
