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STMicroelectronics LD1117AS12TR — Power Management (PMIC / Gate Driver)

STMicroelectronics LD1117AS12TR LDO Regulator, 1.2V Fixed

MPNLD1117AS12TR
Active

STMicroelectronics LD1117AS12TR, positive fixed LDO regulator, 1.2V output, 1A output current, 80dB PSRR at 120Hz, dropout 1.3V max at 1A, SOT-223 package, 0°C to 125°C operating temperature.

$0.8600Ref. price · indicative, final on quote
PackagingTO-261-4, TO-261AA
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

LD1117AS12TR specifications
ParameterValue
Output typeFixed
MountingSurface Mount
Voltage - input15V
Voltage dropout1.3V @ 1A
Voltage - output (Min (Fixed))1.2V
Output current1A
Current - quiescent10 mA
Operating temperature0°C~125°C
PSRR80dB (120Hz)
PackageTape & Reel (TR); Cut Tape (CT)
CaseTO-261-4, TO-261AA
Protection featuresOver Current, Over Temperature
Number of regulators1
Output configurationPositive

Product details

1.2 V fixed rail for noise-sensitive loads

Operating temperature covers 0°C to 125°C, which suits indoor industrial enclosures, telecom racks, and commercial equipment. The 0°C floor excludes unheated outdoor or cold-storage environments. Protection features include over-current and over-temperature shutdown, reducing the need for external supervisory components in fault-prone auxiliary supplies.

SOT-223 footprint and supply posture

The part is housed in an SOT-223 surface-mount package (supplier device package SOT-223, also listed as TO-261-4). The SOT-223 footprint is common in reflow assembly; the tab is the output (Vout) and carries the bulk of the thermal dissipation. For 1 A continuous load, ensure adequate copper area on the PCB. No last-time-buy or obsolescence risk on the current BOM.

Frequently asked questions

Is LD1117AS12TR equivalent to AMS1117-1.2?

Both are 1.2 V fixed LDO regulators in SOT-223 with 1 A output and similar dropout. Pinout and footprint are compatible, but verify the AMS1117-1.2's PSRR and quiescent current against your noise budget — the LD1117AS12TR's 80 dB at 120 Hz is a strong spec for analog rails.

What is the PSRR of LD1117AS12TR?

The LD1117AS12TR provides 80 dB of power-supply rejection at 120 Hz, making it well-suited for filtering mains ripple in analog supply rails.