LND317 Datasheet, PDF (1/4 Pages) Linear Dimensions Semiconductor – 3-Terminal Adjustable Regulators

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DATA SHEET
GENERAL DESCRIPTION
The LND317 is an adjustable 3-terminal positive-
voltage regulator capable of supplying 1.5A over a
differential voltage range of 3V to 40V. It is
exceptionally easy to use and requires only two
external resistors to set the output voltage. Both
input and output regulation is better than standard
fixed regulators.
In addition to higher performance than fixed
regulators, the LND317 has full overload
protection available only in integrated circuits.
Included on the chip are current limit, thermal
overload protection, and safe-area protection. All
overload protection circuitry remains fully
functional even if the adjustment terminal is
disconnected. Normally, no capacitors are
needed unless the device is situated far from the
input filter capacitors in which case an input
bypass is needed. An optional output capacitor
can be added to improve transient response.
The primary applications of this device is that of a
programmable output regulator, but by connecting
a fixed resistor between adjustment terminal and
the output terminal, the device can be used as a
precision current regulator. Even though the
regulator is floating and sees only the input-to -
output differential voltage, use of these devices to
regulate output voltages that would cause the
maximum-rated differential voltage to be
exceeded if the output became shorted to ground
is not recommended.
LND317
3-Terminal Adjustable Regulators
FEATURES
• Output Voltage Range Adjustable
from 1.2V to 37V
• Output Current Capability of 1.5A Max
• Input Regulation Typically 0.01% per
Input-Volt Change
• Output Regulation Typically 0.1%
• Peak Output Current Constant Over
Temperature Range of Regulator
• Popular 3-Lead TO-220 Package
• Ripple Rejection Typically 80 dB
• Direct Replacement for National
LM317
TO-220
(Top View)
INPUT
OUTPUT
ADJUST
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel [phone] • fax [phone] • www.lineardimensions.com •