MAX738ACWE Datasheet Download

Part No.:
MAX738ACWE
Download:
Download Datasheet
Description:
[5V, Step-Down, Current-Mode PWM DC-DC Converters]
File Size:
230 K
Page:
16 Pages
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Manufacturer:
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
PCB Prototype
 MAX738ACWE Datasheet Page:2MAX738ACWE Datasheet Page:3MAX738ACWE Datasheet Page:4MAX738ACWE Datasheet Page:5MAX738ACWE Datasheet Page:6MAX738ACWE Datasheet Page:7MAX738ACWE Datasheet Page:8MAX738ACWE Datasheet Page:9 
19-0165; Rev 2; 1/96
5V, Step-Down,
Current-Mode PWM DC-DC Converters
__________________General Description
The MAX730A/MAX738A/MAX744A are 5V-output
CMOS, step-down switching regulators. The MAX738A/
MAX744A accept inputs from 6V to 16V and deliver
750mA. The MAX744A guarantees 500mA load capa-
bility for inputs above 6V and has tighter oscillator fre-
quency limits for low-noise (radio) applications. The
MAX730A accepts inputs between 5.2V and 11V and
delivers 450mA for inputs above 6V. Typical efficien-
cies are 85% to 96%. Quiescent supply current is
1.7mA and only 6µA in shutdown.
Pulse-width modulation (PWM) current-mode control
provides precise output regulation and excellent tran-
sient responses. Output voltage accuracy is guaran-
teed to be ±5% over line, load, and temperature varia-
tions. Fixed-frequency switching 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.
The MAX730A/MAX738A/MAX744A also feature cycle-
by-cycle current limiting, overcurrent limiting, undervolt-
age lockout, and programmable soft-start protection.
________________________________Features
o
750mA Load Currents (MAX738A/MAX744A)
o
High-Frequency, Current-Mode PWM
o
159kHz to 212.5kHz Guaranteed Oscillator
Frequency Limits (MAX744A)
o
85% to 96% Efficiencies
o
1.7mA Quiescent Current
o
6µA Shutdown Supply Current
o
Single Preselected Inductor Value,
No Component Design Required
o
Overcurrent, Soft-Start, and Undervoltage
Lockout Protection
o
Cycle-by-Cycle Current Limiting
o
8-Pin DIP/SO Packages (MAX730A)
MAX730A/MAX738A/MAX744A
_________________Ordering Information
PART
MAX730ACPA
MAX730ACSA
MAX730AC/D
MAX730AEPA
MAX730AESA
MAX730AMJA
TEMP. RANGE
0°C to +70°C
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
PIN-PACKAGE
8 Plastic DIP
8 SO
Dice*
8 Plastic DIP
8 SO
8 CERDIP
___________________________Applications
Portable Instruments
Cellular Phones and Radios
Personal Communicators
Distributed Power Systems
Computer Peripherals
Ordering Information continued at end of data sheet.
*Contact factory for dice specifications.
__________Typical Operating Circuit
INPUT
6V TO 16V
V+
33µH
LX
OUTPUT
5V
_________________Pin Configurations
TOP VIEW
68µF
SHDN
1
MAX738A
MAX744A
ON/OFF
SHDN
OUT
8
7
V+
LX
GND
OUT
100µF
REF
2
SS
3
CC
4
MAX730A
MAX738A
MAX744A
DIP
6
5
REF
SS
GND
CC
Pin Configurations continued on last page.
________________________________________________________________
Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800