19-0102; Rev 3; 9/95
5A/2A Step-Down, PWM,
Switch-Mode DC-DC Regulators
_______________General Description
The MXL1074/MXL1076 are monolithic, bipolar, pulse-
width modulation (PWM), switch-mode DC-DC regulators
optimized for step-down applications. The MXL1074 is
rated at 5A, while the MXL1076 is rated at 2A. Few exter-
nal components are needed for standard operation
because the power switch, oscillator, and control circuitry
are all on-chip. Employing a classic buck topology, these
regulators perform high-current step-down functions, but
can also be configured as an inverter, a negative boost
converter, or a flyback converter.
The regulators have excellent dynamic and transient-
response characteristics, while featuring cycle-by-cycle
current limiting to protect against overcurrent faults and
short-circuit output faults. The MXL1074/MXL1076 also
have a wide 8V to 40V input range in the step-down
configuration. In inverting and step-up configurations,
the input can be as low as 5V.
The MXL1074/MXL1076 are available in a 5-pin TO-220
package. The devices have a preset 100kHz oscillator
frequency and a preset current limit of 6.5A for the
MXL1074, and 2.6A for the MXL1076. The MXL1074/
MXL1076 are pin compatible with the LT1074/LT1076.
____________________________Features
o
Input Range:
Up to 40V
o
5A On-Chip Power Switch (MXL1074)
2A On-Chip Power Switch (MXL1076)
o
Adjustable Output:
2.5V to 35V
o
100kHz Switching Frequency
o
Excellent Dynamic Characteristics
o
Few External Components
o
8.5mA Quiescent Current
o
TO-220 Package
MXL1074/MXL1076
______________Ordering Information
PART
MXL1074CT
MXL1074ET
MXL1076CT
MXL1076ET
TEMP. RANGE
0擄C to +70擄C
-40擄C to +85擄C
0擄C to +70擄C
-40擄C to +85擄C
PIN-PACKAGE
5 TO-220
5 TO-220
5 TO-220
5 TO-220
___________________Pin Configuration
FRONT VIEW
5
4
3
2
1
V
IN
V
SW
GND
V
C
FB
________________________Applications
Distributed Power from High-Voltage Buses
High-Current, High-Voltage Step-Down Applications
High-Current Inverter
Negative Step-Up Converter
Multiple-Output Step-Down Converter
Isolated DC-DC Conversion
MXL1074
MXL1076
5-PIN TO-220
CASE IS CONNECTED TO GROUND. STANDARD PACKAGE HAS
STAGGERED LEADS. CONTACT FACTORY FOR STRAIGHT LEADS.
__________________________________________________Typical Operating Circuits
INPUT
8V TO 40V
V
IN
220碌F
V
C
2.7k
0.01碌F
V
SW
50碌H
OUTPUT
5V AT 5A
INPUT
8V TO 40V
V
IN
MBR745
FB
2.21k
GND
0.01碌F
220碌F
2.8k
470碌F
2.7k
V
C
V
SW
100碌H
OUTPUT
5V AT 2A
MXL1074
MXL1076
FB
MBR745
2.8k
470碌F
2.21k
GND
5A STEP-DOWN CONVERTER
2A STEP-DOWN CONVERTER
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________________________________________________________________
Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
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