Original Creation Date: 08/29/95
Last Update Date: 09/29/95
Last Major Revision Date: 08/29/95
MNLM1575-X-12 REV 0B0 MILITARY DATA SHEET
SIMPLE SWITCHER(TM) 1A STEP-DOWN VOLTAGE REGULATOR
General Description
The LM1575 regulator is a monolithic integrated circuit that provides all the active
functions from a step-down (buck) switching regulator, capable of driving a 1A load with
excellent line and load regulation.
Requiring a minimum number of external components, this regulator is simple to use and
includes internal frequency compensation and a fixed-frequency oscillator.
The LM1575 offers a high-efficiency replacement for popular three-terminal linear
regulators. It substantially reduces the size of the heat sink, and in many cases no heat
sink is required.
A standard series of inductors optimized for use with the LM1575 are available from
several different manufacturers. This feature greatly simplifies the design of switch-mode
power supplies.
Other features include a guaranteed +4% tolerance on output voltage within specified input
voltage and output load conditions, and +10% on the oscillator frequency. External
shutdown is included, featuring 50uA (typical) standby current. The output switch includes
cycle-by-cycle current limiting, as well as thermal shutdown for full protection under
fault conditions.
NS Part Numbers
LM1575J-12-QML
LM1575K-12-QML
Industry Part Number
LM1575-12
Prime Die
LM1575-12
Controlling Document
5962-9167301QEA, QXA
Processing
MIL-STD-883, Method 5004
Quality Conformance Inspection
MIL-STD-883, Method 5005
Subgrp Description Temp ( C)
o
1 Static tests at +25
2 Static tests at +125
3 Static tests at -55
4 Dynamic tests at +25
5 Dynamic tests at +125
6 Dynamic tests at -55
7 Functional tests at +25
8A Functional tests at +125
8B Functional tests at -55
9 Switching tests at +25
10 Switching tests at +125
11 Switching tests at -55
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MILITARY DATA SHEET
MNLM1575-X-12 REV 0B0
Features
- Adjustable version output voltage range, 1.23V to 37V +4% max over line
and load conditions
- Guaranteed 1A output current
- Requires only 4 external components
- 52KHz fixed frequency internal oscillator
- TTL shutdown capability, low power standby mode
- High efficiency
- Uses readily available standard inductors
- Thermal shutdown and current limit protection
Applications
- Simple high-efficiency step-down (buck) regulator
- Efficient pre-regulator for linear regulators
- On-card switching regulators
- Positive to negative converted (Buck-Boost)
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MILITARY DATA SHEET
MNLM1575-X-12 REV 0B0
(Absolute Maximum Ratings)
(Note 1)
Maximum Supply Voltage 45V
ON/OFF Pin Input Voltage -0.3V <V< +Vin
Output Voltage to Ground -1V(Steady State)
Power Dissipation Internally Limited
Storage Temperature Range -65 C to +150 C
Minimum ESD Rating 3KV(C = 100pF, R = 1.5K Ohms)
Lead Temperature
(Soldering, 10 Sec.) 260 C CERDIP 300 C TO3
Maximum Junction Temperature 150 C
Thermal Resistance
ThetaJA 45 C/W Metal Can (Still Air) 10 C/W Metal Can (500LF/Min Air flow) 70 C/W CERDIP (Still Air) 33 C/W CERDIP (500LF/Min Air flow)
ThetaJC 3.3 C/W Metal Can 2.0 C/W CERDIP
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.
Operating Ratings indicate conditions for which the device is intended to be
functional, but do not guarantee specific performance limits. For guaranteed
specifications and test conditions, see the Electrical Characteristics.
Recommended Operating Conditions
Temperature Range -55 C < TA < +125 C
Supply Voltage 40V
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MNLM1575-X-12 REV 0B0 MILITARY DATA SHEET
Electrical Characteristics
ELECTRICAL CHARACTERISTICS: SYSTEM PARAMETERS
(The following conditions apply to all the following parameters, unless otherwise specified.)
DC: Vin = 25V, and Iload = 200mA.
SYMBOL PARAMETER CONDITIONS NOTES PIN-
NAME MIN MAX UNIT SUB-
GROUPS
Vout Output Voltage 1 11.88 12.12 V 1
0.2A < Iload < 1A, 15V < Vin < 40V 1 11.64 12.36 V 1
0.2A < Iload < 1A, 15V < Vin < 40V 1 11.52 12.48 V 2, 3
ELECTRICAL CHARACTERISTICS: DEVICE PARAMETERS
(The following conditions apply to all the following parameters, unless otherwise specified.)
DC: Vin = 25V, and Iload = 200mA.
Vsat Saturation
Voltage Iout = 1A 2 1.2 V 1
2 1.4 V 2, 3
Icl Current Limit Peak Current, tON < 3uS 2 1.7 3.0 A 1
Peak Current, tON < 3uS 2 1.3 3.2 A 2, 3
Il Output Leakage
Current Vin = 35V, Output = 0V 4 2 mA 1
Vin = 35V, Output = -1V 4 30 mA 1
Iq Quiescent Current 4 10 mA 1
4 12 mA 2, 3
Istby Standby Quiescent
Current ON/OFF Pin = 5V (OFF) 200 uA 1
ON/OFF Pin = 5V (OFF) 500 uA 2, 3
AC ELECTRICAL CHARACTERISTICS: DEVICE PARAMETERS
(The following conditions apply to all the following parameters, unless otherwise specified.)
AC: Vin = 25V, and Iload = 200mA.
fo Oscillator
Frequency 47 58 KHz 4
43 62 KHz 5, 6
Dc Max Duty Cycle
(ON) 393 %9
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MNLM1575-X-12 REV 0B0 MILITARY DATA SHEET
Electrical Characteristics
ELECTRICAL CHARACTERISTICS: ON/OFF CONTROL
(The following conditions apply to all the following parameters, unless otherwise specified.)
DC: Vin = 25V, and Iload = 200mA.
SYMBOL PARAMETER CONDITIONS NOTES PIN-
NAME MIN MAX UNIT SUB-
GROUPS
Vih ON/OFF Pin Logic
Input Level Vout = 0V 2.2 V 1
Vih ON/OFF Pin Logic
Input Level Vout = 0V 2.4 V 2, 3
Vil ON/OFF Pin Logic
Input Level Vout = 12V 1.0 V 1
Vil ON/OFF Pin Logic
Input Level Vout = 12V .8 V 2, 3
Iih ON/OFF Pin Input
Current ON/OFF Pin = 5V (OFF) 30 uA 1
Iil ON/OFF Pin Input
Current ON/OFF Pin = 0V (ON) 10 uA 1
Note 1: External components such as the catch diode, inductor, input and output capacitors
can affect switching regulator system performance.
Note 2: Output sourcing current. No diode, inductor or capacitor connected to output.
Note 3: Feedback removed from output and connected to 0V.
Note 4: Feedback removed from output and connected to 25V to force the output transistor OFF.
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MILITARY DATA SHEET
MNLM1575-X-12 REV 0B0
Graphics and Diagrams
GRAPHICS# DESCRIPTION
J16ARL CERDIP (J), 16 LEAD (P/P DWG)
KA04BRA METAL CAN, TO-3, 4 LEAD, LOW PROFILE (P/P DWG)
See attached graphics following this page.
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