STMicroelectronics

LD1117ADT33TR - 3.3V Fixed 800mA LDO Regulator | STMicroelectronics

부품 번호: LD1117ADT33TR ✓ 활성
재고 있음 영업일 기준 1~3일 내 발송
3.3 V Vdss 800 mA Id 50 °C/W Rds(on) DPAK (TO-252) Package
시작가 $0.19 USD / 개
MOQ: 1 |
가격 업데이트: 2026-08-11
볼륨 가격
수량 단가 합계
1 $0.45 $0.45
10 $0.38 $3.80
100 $0.29 $29.00
500 $0.24 $120.00
1,000 $0.19 $190.00
ℹ️ 모든 가격은 USD 기준입니다

LD1117ADT33TR 개요

The STMicroelectronics LD1117ADT33TR is a low-dropout (LDO) linear voltage regulator providing a fixed 3.3V output with a maximum output current of 800mA. It is housed in a DPAK (TO-252) surface-mount package, designed for a wide range of consumer, industrial, and computing applications. The device operates with an input voltage range from 4.75V to 15V, making it suitable for 5V and 12V rails.

An LDO (Low-Dropout) linear regulator is a type of voltage regulator that maintains a stable output voltage even when the input voltage is very close to the output voltage. Unlike standard linear regulators, LDOs use a pass transistor operating in the saturation region, allowing a low dropout voltage. In the system hierarchy, an LDO is a linear regulator, which is a type of voltage regulator, which falls under power management ICs, which are semiconductors. This hierarchy is essential for understanding where the LD1117ADT33TR fits in power management design.

Key features of the LD1117ADT33TR include a dropout voltage of typically 1.1V at 800mA load, a quiescent current of 5mA, and a line regulation of 0.2% (typical). It also offers thermal shutdown and internal current limiting, providing robust protection for the load. The fixed 3.3V output eliminates the need for external resistor dividers, simplifying design and reducing component count.

The LD1117ADT33TR is built on a bipolar process, offering low noise and fast transient response. The DPAK package provides a thermal resistance of 50°C/W (junction-to-ambient), allowing moderate power dissipation without a heatsink. The device is RoHS compliant and lead-free, meeting modern environmental standards.

Typical applications include powering microcontrollers, FPGAs, and digital logic in embedded systems, as well as providing a clean 3.3V rail for sensors and interface circuits. It is also used in set-top boxes, routers, and other consumer electronics where a stable 3.3V supply is required.

When designing with the LD1117ADT33TR, ensure adequate input-output voltage headroom to maintain regulation. A minimum input voltage of 4.75V is required for 3.3V output. Use a 10µF output capacitor for stability, and place it close to the output pin. The thermal pad should be connected to a large copper area for heat dissipation.

드롭인 대체품: LD1117ADT33TR — 동일 패키지, 핀 호환. PCB 재작업이 필요한 다른 패키지 부품은 제외됩니다.

빠른 비교 도구 — 나란히 비교할 대체 부품을 선택하십시오:

LD1117ADT33TR

✅ 드롭인
STMicroelectronics
📦 DPAK (TO-252)
Fixed · 3.3 V · 800 mA · 4.75 V to 15 V · 1.1 V (typical at 800 mA) · 5 mA · 0.2% (typical) · 0.4% (typical)

✓ 재고 있음

$0.19 / 개

데이터시트 보기 →

AMS1117-3.3

✅ 드롭인 ⚠️ 사양 미검증
📦 DPAK (TO-252)
Higher output current (1A vs 800mA), same pinout

📋 참조 대체품 (카탈로그에 없음)

AP1117-33

✅ 드롭인 ⚠️ 사양 미검증
📦 DPAK (TO-252)
Similar specs, 1A output, same pinout

📋 참조 대체품 (카탈로그에 없음)

ℹ️ 2 교차 패키지 부품은 숨겨졌습니다 — 다른 패키지는 PCB 재작업이 필요하며 진정한 드롭인 대체품이 아닙니다. 문의하기 교차 패키지 제안이 필요하면 다음을 참조하십시오.

LD1117ADT33TR 최대 정격 & 전기적 특성

출력 유형 Fixed
출력 전압 3.3 V
최대 출력 전류 800 mA
입력 전압 범위 4.75 V to 15 V
드롭아웃 전압 1.1 V (typical at 800 mA)
대기 전류 5 mA
Line Regulation 0.2% (typical)
Load Regulation 0.4% (typical)
열 저항, 접합-주변 50 °C/W
동작 온도 범위 -40°C to +125°C
패키지 DPAK (TO-252)
실장 유형 Surface Mount
MSL 레벨 1 (unlimited)
RoHS 상태 Compliant
Lead-Free Yes

LD1117ADT33TR 핀 구성

DPAK (TO-252) Package Pinout Diagram DPAK TO-252 3-pin SMD power, JEDEC TO-252. Thermal tab. 1 2 3 DPAK (TO-252)
핀 1 GND — Ground
핀 2 VOUT — Regulated 3.3V output
핀 3 VIN — Input voltage (4.75V to 15V)
핀 Tab VOUT — Exposed pad connected to VOUT

일반적인 애플리케이션

LD1117ADT33TR 적합 용도: 6 애플리케이션s: Microcontroller Power Supply, FPGA Core Voltage, Sensor Interface, Set-Top Box, Router and Networking Equipment, Industrial Control.

🔧

Microcontroller Power Supply

The LD1117ADT33TR provides a stable 3.3V rail for microcontrollers, ensuring reliable operation. Its 800mA output current is sufficient for most MCUs and peripheral circuits. The low dropout voltage allows operation from 5V rails with minimal power loss. The fixed output simplifies design, and the thermal shutdown protects the MCU from overheating. In a typical application, the LDO is placed between the 5V supply and the MCU's VDD pin, with a 10µF capacitor on the output for stability. The low quiescent current of 5mA is acceptable for non-battery-powered systems. Compared to switching regulators, the LDO provides a cleaner output with no switching noise, which is critical for analog peripherals. However, power dissipation is higher; for a 5V-to-3.3V conversion at 500mA, power dissipation is 0.85W, requiring adequate PCB copper for heat sinking.

🔧

FPGA Core Voltage

The LD1117ADT33TR can power the core logic of small FPGAs that require 3.3V. Its 800mA output current is suitable for low-power FPGAs like the ICE40 series. The low dropout voltage ensures regulation even with a 5V input. The thermal shutdown protects the FPGA from thermal damage. In a typical design, the LDO is placed close to the FPGA's VCCINT pins, with multiple decoupling capacitors. The fixed 3.3V output eliminates the need for external resistors. The LDO's fast transient response helps maintain stable voltage during FPGA switching activity. However, for larger FPGAs with higher current demands, a switching regulator may be more efficient. The LD1117ADT33TR is best for small, low-power FPGAs in cost-sensitive applications.

🧩

Sensor Interface

The LD1117ADT33TR provides a clean 3.3V supply for sensors and analog front-ends. Its low noise and stable output are essential for accurate sensor readings. The 800mA output current can power multiple sensors. The thermal shutdown protects the sensors from over-temperature. In a typical application, the LDO is used to power a temperature sensor and an ADC, with a 10µF capacitor on the output. The fixed 3.3V output simplifies the design. The LDO's line regulation of 0.2% ensures stable output even with input voltage variations. Compared to switching regulators, the LDO eliminates switching noise that could corrupt sensor measurements. However, the LDO's quiescent current of 5mA may be a concern for battery-powered sensor nodes, where a low-quiescent LDO would be preferred.

📺

Set-Top Box

The LD1117ADT33TR is used in set-top boxes to provide a stable 3.3V rail for the main processor and tuner. Its 800mA output current is sufficient for these components. The low dropout voltage allows operation from a 5V rail. The thermal shutdown protects the device in case of overload. In a typical set-top box, the LDO is placed on the main board, with a heat sink or copper area for dissipation. The fixed 3.3V output simplifies the power supply design. The LDO's low noise is important for the tuner's RF performance. Compared to switching regulators, the LDO provides a cleaner output, but at the cost of efficiency. For a 12V-to-3.3V conversion at 500mA, power dissipation is 4.35W, requiring a heatsink. The LD1117ADT33TR is a cost-effective solution for set-top boxes.

🌐

Router and Networking Equipment

The LD1117ADT33TR provides a stable 3.3V supply for networking processors and PHY chips. Its 800mA output current is adequate for these components. The low dropout voltage allows operation from a 5V rail. The thermal shutdown protects the equipment from overheating. In a typical router, the LDO is used to power the main SoC and Ethernet PHY, with a 10µF capacitor on the output. The fixed 3.3V output simplifies the design. The LDO's low noise is important for the PHY's signal integrity. Compared to switching regulators, the LDO provides a cleaner output, but with lower efficiency. For a 5V-to-3.3V conversion at 500mA, power dissipation is 0.85W, which is manageable with proper PCB layout. The LD1117ADT33TR is a reliable choice for networking equipment.

🏭

Industrial Control

The LD1117ADT33TR is used in industrial control systems to provide a stable 3.3V supply for PLCs and sensors. Its 800mA output current is sufficient for these applications. The wide input voltage range (up to 15V) allows operation from 24V industrial rails with a pre-regulator. The thermal shutdown protects the device in harsh environments. In a typical industrial application, the LDO is used to power a microcontroller and fieldbus interface, with a 10µF capacitor on the output. The fixed 3.3V output simplifies the design. The LDO's operating temperature range of -40°C to +125°C makes it suitable for industrial environments. Compared to switching regulators, the LDO provides a cleaner output, but with higher power dissipation. For a 24V-to-3.3V conversion at 500mA, power dissipation is 10.35W, requiring a heatsink or a pre-regulator. The LD1117ADT33TR is a robust choice for industrial control.

추천 제품 요약

STM32F103C8T6 STMicroelectronics 사용처: Microcontroller Power Supply, Microcontroller Power Supply ATmega328P Microcontroller requiring 3.3V supply 사용처: Microcontroller Power Supply ICE40LP384 Low-power FPGA requiring 3.3V core 사용처: FPGA Core Voltage Cyclone 10 LP FPGA requiring 3.3V core 사용처: FPGA Core Voltage TMP117 Texas Instruments 사용처: Sensor Interface ADS1115 ADC requiring 3.3V supply 사용처: Sensor Interface BCM7230 Set-top box SoC requiring 3.3V supply 사용처: Set-Top Box Si2168 Tuner requiring 3.3V supply 사용처: Set-Top Box MT7628 Router SoC requiring 3.3V supply 사용처: Router and Networking Equipment RTL8211F Realtek 사용처: Router and Networking Equipment STM32F407 Industrial microcontroller requiring 3.3V supply 사용처: Industrial Control ISO1050 CAN transceiver requiring 3.3V supply 사용처: Industrial Control
What is the output voltage of LD1117ADT33TR?
The LD1117ADT33TR provides a fixed output voltage of 3.3V. According to the STMicroelectronics LD1117A datasheet, the output is fixed at 3.3V with an accuracy of ±1% at room temperature.
What is the maximum output current of LD1117ADT33TR?
The LD1117ADT33TR can deliver a maximum output current of 800mA. This is specified in the STMicroelectronics datasheet, making it suitable for powering moderate loads such as microcontrollers and small FPGAs.
What is the input voltage range of LD1117ADT33TR?
The LD1117ADT33TR operates with an input voltage range from 4.75V to 15V. This allows it to be powered from standard 5V or 12V rails, as stated in the STMicroelectronics datasheet.
What is the dropout voltage of LD1117ADT33TR?
The dropout voltage of the LD1117ADT33TR is typically 1.1V at 800mA load. This means the input voltage must be at least 1.1V above the output voltage to maintain regulation, as per the datasheet.
Is LD1117ADT33TR suitable for battery-powered applications?
The LD1117ADT33TR is not ideal for battery-powered applications due to its relatively high quiescent current of 5mA. For battery-powered designs, consider low-quiescent-current LDOs like the TPS7A02 or LP5907, which offer microamp-level quiescent current.
What is the difference between LD1117ADT33TR and LD1117DT33TR?
The LD1117ADT33TR and LD1117DT33TR are both 3.3V LDOs from STMicroelectronics, but they differ in package: the ADT33TR is in DPAK (TO-252), while the DT33TR is in SOT-223. They are not pin-compatible due to different package footprints, so they are not drop-in replacements for each other.
Can LD1117ADT33TR be used for audio applications?
The LD1117ADT33TR is not specifically designed for audio applications, as it has higher noise compared to dedicated audio LDOs. For audio, consider ultra-low-noise LDOs like the TPS7A4701 or LT3045, which offer noise levels below 5µVrms.
What is the thermal resistance of LD1117ADT33TR?
The LD1117ADT33TR has a junction-to-ambient thermal resistance of 50°C/W. This means at 1W power dissipation, the junction temperature rises 50°C above ambient. Adequate PCB copper area is required for heat dissipation.
What is the quiescent current of LD1117ADT33TR?
The quiescent current of the LD1117ADT33TR is 5mA typical. This is the current consumed by the regulator itself when supplying a load, and it should be considered in power budget calculations.
Is LD1117ADT33TR RoHS compliant?
Yes, the LD1117ADT33TR is RoHS compliant and lead-free. This is confirmed in the STMicroelectronics datasheet and product page, making it suitable for use in products sold in regions with RoHS regulations.
What is the lead time for LD1117ADT33TR?
The lead time for LD1117ADT33TR is typically 8-12 weeks from major distributors like DigiKey and Mouser, depending on stock levels. As of 2026-08-07, it is generally in stock at major distributors.
Where can I buy LD1117ADT33TR online?
LD1117ADT33TR can be purchased from authorized distributors such as DigiKey, Mouser, and Farnell. As of 2026-08-07, it is available in stock at these distributors, with pricing starting at $0.45 for single units.
What is the price of LD1117ADT33TR?
As of 2026-08-07, the price of LD1117ADT33TR is approximately $0.45 for 1 unit, $0.38 for 10 units, $0.29 for 100 units, $0.24 for 500 units, and $0.19 for 1000 units, based on distributor pricing from DigiKey and Mouser.
What is the best drop-in replacement for LD1117ADT33TR?
The best drop-in replacement for LD1117ADT33TR is the AMS1117-3.3 from Advanced Monolithic Systems, which shares the same DPAK (TO-252) package and pinout, and offers a similar 3.3V fixed output with 1A current capability. Other drop-in options include the NCP1117ST33T3G from onsemi and the AP1117-33 from Diodes Incorporated.
Can LD1117ADT33TR be replaced by AMS1117-3.3?
Yes, the AMS1117-3.3 is a drop-in replacement for LD1117ADT33TR. Both are 3.3V fixed LDOs in DPAK (TO-252) package with pin-to-pin compatibility. The AMS1117-3.3 offers a higher output current of 1A, making it a suitable alternative.
What is the difference between LD1117ADT33TR and AMS1117-3.3?
The LD1117ADT33TR and AMS1117-3.3 are both 3.3V LDOs in DPAK package, but the AMS1117-3.3 has a higher maximum output current of 1A compared to 800mA for the LD1117ADT33TR. The dropout voltage is similar, around 1.1V at full load.
Where can I download the LD1117ADT33TR datasheet PDF?
The LD1117ADT33TR datasheet PDF can be downloaded from the STMicroelectronics website at https://www.st.com/resource/en/datasheet/ld1117a.pdf. It is also available on distributor websites like DigiKey and Mouser.
Where can I find the LD1117ADT33TR pinout?
The LD1117ADT33TR pinout is available in the datasheet on page 3. The DPAK package has three pins: Pin 1 (GND), Pin 2 (VOUT), and Pin 3 (VIN), with the tab connected to VOUT. This is detailed in the STMicroelectronics datasheet.
What are the key specifications of LD1117ADT33TR that engineers should know?
The LD1117ADT33TR is a fixed 3.3V LDO with 800mA output current, input range 4.75V to 15V, dropout voltage 1.1V typical, quiescent current 5mA, and thermal resistance 50°C/W. It is in DPAK package, RoHS compliant, and operates from -40°C to +125°C. These specs are critical for power supply design.
Is LD1117ADT33TR the same as AMS1117-3.3?
No, LD1117ADT33TR and AMS1117-3.3 are not the same part, but they are functionally equivalent and pin-compatible. Both are 3.3V LDOs in DPAK package, but the AMS1117-3.3 has a higher output current rating of 1A.

엔지니어링 참조 데이터: LD1117ADT33TR — 비교, 설계 지침 및 규정 준수 정보.

선택 가이드

Choose the LD1117ADT33TR when you need a reliable, fixed 3.3V LDO with 800mA output current and a wide input voltage range up to 15V. It is ideal for industrial and consumer applications where a clean, stable 3.3V rail is required. If you need a higher output current of 1A, consider the AMS1117-3.3 or AP1117-33, which are drop-in compatible in DPAK package. If you prefer a smaller SOT-223 package, the LD1117DT33TR or NCP1117ST33T3G are options, but they are not pin-compatible with the DPAK footprint. For battery-powered applications, look for low-quiescent-current LDOs like the TPS7A02. The LD1117ADT33TR is a cost-effective choice for most non-battery-powered designs.

대체품과의 비교

파라미터 이 제품 LD1117DT33TR AMS1117-3.3 NCP1117ST33T3G AP1117-33
Package DPAK (TO-252) SOT-223 DPAK (TO-252) SOT-223 DPAK (TO-252)
Brand STMicroelectronics STMicroelectronics Advanced Monolithic Systems onsemi Diodes Incorporated
Output Voltage 3.3V 3.3V 3.3V 3.3V 3.3V
Maximum Output Current 800mA 800mA 1A 1A 1A
Input Voltage Range 4.75V to 15V 4.75V to 15V 4.75V to 12V 4.75V to 18V 4.75V to 18V
Dropout Voltage 1.1V typical 1.1V typical 1.1V typical 1.1V typical 1.1V typical
Quiescent Current 5mA 5mA 5mA 5mA 5mA
Operating Temperature Range -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C

주요 차별점

  • Wide input voltage range up to 15V (vs AMS1117-3.3)
  • Lower quiescent current than some alternatives (vs NCP1117ST33T3G)
  • Proven STMicroelectronics quality (vs AP1117-33)

설계 노트

The LD1117ADT33TR has a junction-to-ambient thermal resistance of 50°C/W. At 5V input and 3.3V output with 800mA load, power dissipation is (5-3.3)*0.8 = 1.36W, causing a temperature rise of 68°C. Ensure adequate PCB copper area (at least 1 square inch) connected to the thermal pad to keep junction temperature below 125°C. For higher input voltages, consider a heatsink or a pre-regulator.

Place a 10µF ceramic capacitor on the output and a 10µF capacitor on the input, as close to the pins as possible. The output capacitor is required for stability. Use a 0.1µF capacitor in parallel for high-frequency decoupling. The thermal pad should be soldered to a large copper area for heat dissipation.

Do not exceed the maximum input voltage of 15V. Ensure the input voltage is at least 4.75V to maintain regulation. The LD1117ADT33TR is a fixed output device; do not attempt to adjust the output voltage. Use a proper heat sink for high power dissipation. Avoid reverse polarity on the input.

규정 준수 정보

RoHS
Compliant
REACH
Compliant
AEC-Q100
Not Applicable
무연
Yes
무할로겐
Unknown
분쟁 광물
Compliant

RoHS compliant and lead-free per STMicroelectronics datasheet. Not AEC-Q100 qualified. Halogen-free status not specified in the provided data.

데이터 검증일: 2026-10-16 — XAIPART 부품 엔지니어링 팀이 검증하고 관리한 데이터

관련 검색

LD1117ADT33TR LD1117ADT33TR datasheet STMicroelectronics LD1117ADT33TR 3.3V LDO regulator 800mA DPAK LDO regulator LD1117ADT33TR microcontroller power supply LD1117ADT33TR vs AMS1117-3.3 LD1117ADT33TR drop-in replacement LD1117ADT33TR buy price what is the output voltage of LD1117ADT33TR LD1117ADT33TR pinout DPAK low dropout regulator 3.3V fixed

관련 부품 & 용어

STMicroelectronics LD1117ADT33TR LD1117DT33TR AMS1117-3.3 NCP1117ST33T3G AP1117-33 LDO linear regulator voltage regulator power management IC DPAK TO-252 SOT-223 RoHS lead-free thermal shutdown current limiting dropout voltage quiescent current microcontroller FPGA set-top box router industrial control
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