Skip to main content
Log in
STMicroelectronics LD1117ADT-TR — Analog & Data Acquisition

LD1117ADT-TR STMicroelectronics Adjustable LDO 1A DPAK

MPNLD1117ADT-TR
Active

STMicroelectronics LD1117ADT-TR, adjustable positive LDO regulator, 1A output, 80dB PSRR at 120Hz, 1.3V dropout max at 1A, DPAK (TO-252-3) surface-mount package.

$0.7500Ref. price · indicative, final on quote
STMicroelectronics LD1117ADT-TR datasheet (PDF)
PackagingTO-252-3, DPak (2 Leads + Tab), SC-63
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

LD1117ADT-TR specifications
ParameterValue
Output typeAdjustable
MountingSurface Mount
Voltage - input15V
Voltage dropout1.3V @ 1A
Voltage - output15V
Voltage - output (Min (Fixed))1.25V
Output current1A
Current - quiescent5 mA
Operating temperature0°C~125°C
PSRR80dB (120Hz)
PackageTape & Reel (TR); Cut Tape (CT)
CaseTO-252-3, DPak (2 Leads + Tab), SC-63
Protection featuresOver Current, Over Temperature
Number of regulators1
Output configurationPositive

Product details

Adjustable LDO for post-switcher rails

The LD1117ADT-TR is a 1A adjustable positive LDO regulator from STMicroelectronics, in a DPAK (TO-252-3) surface-mount package.

Dropout headroom and output range

Maximum dropout is 1.3V at the full 1A load — so a 5V rail needs at least 6.3V input to stay in regulation at peak current. The adjustable output spans 1.25V up to 15V, set by a resistive divider on the ADJ pin.

Active production, DPAK footprint

Protection and quiescent current

Built-in over-current and over-temperature protection cover the common fault cases — shorted output or excessive ambient. Quiescent current is 5 mA typical, which sets the light-load efficiency floor.

Frequently asked questions

Is LD1117ADT-TR equivalent to the fixed-output LD1117 variants?

The LD1117ADT-TR is the adjustable-output version (1.25V to 15V range). Fixed-output siblings like LD1117DT33 (3.3V) or LD1117DT50 (5.0V) share the same pinout and DPAK package, but the adjust version requires two external resistors to set Vout. They are not drop-in replacements without a board change.

Can I get 3.3V out from the LD1117ADT-TR?

Yes — use a resistor divider from Vout to ADJ. The formula is Vout = 1.25V × (1 + R2/R1). For 3.3V, a typical pair is R1=124Ω, R2=205Ω. The 1.25V reference is stable across the full 1A load and temperature range.