LM3411_15 Datasheet, PDF (1/24 Pages) Texas Instruments – LM3411 Precision Secondary Regulator/Driver

LM3411
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SNVS113E – DECEMBER 1999 – REVISED APRIL 2013
LM3411 Precision Secondary Regulator/Driver
Check for Samples: LM3411
FEATURES
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•2 Fixed Voltages of 3.3V and 5.0V with Initial
Tolerance of ±1% for Standard Grade and
±0.5% for A Grade
• Custom Voltages Available (3V–17V)
• Wide Output Current Range, 20 μA–15 mA
• Low Temperature Coefficient
• Available in 5-Lead SOT23-5 Surface Mount
Package (Tape and Reel)
APPLICATIONS
• Secondary Controller for Isolated DC/DC PWM
Switching Regulators Systems
• Use with LDO Regulator for High-Precision
Fixed Output Regulators
• Precision Monitoring Applications
• Use with many Types of Regulators to
Increase Precision and Improve Performance
DESCRIPTION
The LM3411 is a low power fixed-voltage (3.3V or
5.0V) precision shunt regulator designed specifically
for driving an optoisolator to provide feedback
isolation in a switching regulator.
The LM3411 circuitry includes an internally
compensated op amp, a bandgap reference, NPN
output transistor, and voltage setting resistors.
A trimmed precision bandgap reference with
temperature drift curvature correction, provides a
ensured 1% precision over the operating temperature
range (A grade version). The amplifier's inverting
input is externally accessible for loop frequency
compensation when used as part of a larger servo
system. The output is an open-emitter NPN transistor
capable of driving up to 15 mA of load current.
Because of its small die size, the LM3411 has been
made available in the sub-miniature 5-lead SOT23-5
surface mount package. This package is ideal for use
in space critical applications.
Although its main application is to provide a precision
output voltage (no trimming required) and maintain
very good regulation in isolated DC/DC converters, it
can also be used with other types of voltage
regulators or power semiconductors to provide a
precision output voltage without precision resistors or
trimming.
Typical Application and Functional Diagram
Figure 1. Basic Isolated DC/DC Converter
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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