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LM317LCDR

LM317LCDR – Texas Instruments Adjustable Positive Regulator

MPNLM317LCDR
Active

Texas Instruments LM317LCDR, adjustable positive voltage regulator, 100 mA output, 8-SOIC surface-mount package, active lifecycle.

$0.4900Ref. price · indicative, final on quote
Packaging8-SOIC (0.154", 3.90mm Width)
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

LM317LCDR specifications
ParameterValue
Output typeAdjustable
MountingSurface Mount
Voltage - input38V
Voltage - output32V
Voltage - output (Min (Fixed))1.2V
Output current100mA
Current - quiescent2.5 mA
Operating temperature0°C~125°C
PSRR80dB ~ 65dB (120Hz)
PackageTape & Reel (TR); Cut Tape (CT)
Case8-SOIC (0.154\", 3.90mm Width)
Protection featuresOver Current, Over Temperature, Short Circuit
Number of regulators1
Output configurationPositive

Product details

It accepts an input voltage up to 38 V and produces an adjustable output from 1.2 V to 32 V. The single-regulator design suits point-of-load or post-regulation stages where a fixed-output part would force a second supply rail.

PSRR and noise rejection for sensitive loads

Power-supply rejection ratio is specified at 80 dB to 65 dB at 120 Hz. The 80 dB floor at line frequency means the regulator attenuates 120 Hz ripple by a factor of 10,000; the roll-off to 65 dB at higher frequencies is typical for a three-terminal adjustable regulator. For a 5 V rail with 100 mVpp of 120 Hz ripple, the output ripple sits below 10 µVpp — adequate for most analog front-ends that do not require a post-LDO filter.

Protection features and quiescent current

Built-in protection includes over-current, over-temperature, and short-circuit shutdown. The quiescent current is 2.5 mA, which sets the minimum load requirement for regulation — the output must sink at least 2.5 mA to maintain the reference voltage. For very light loads, a preload resistor may be needed.

Frequently asked questions

What package does the LM317LCDR come in?

It is offered in Tape & Reel (TR) and Cut Tape (CT) options.