Overview
The LD1117S33CTR is a fixed low drop positive voltage regulator produced by STMicroelectronics. This regulator is part of the LD1117 series, known for its high efficiency and low dropout voltage. The LD1117S33CTR is specifically designed to provide a fixed output voltage of 3.3V and can supply up to 800 mA of output current. It is packaged in a SOT-223 (TO-261-4, SC-73) surface mount package, which optimizes thermal characteristics and offers a space-saving design. The regulator features an NPN pass transistor, which ensures high efficiency by allowing the quiescent current to flow mostly into the load.
Key Specifications
| Attribute | Value |
|---|---|
| Input Voltage - Max | 15V |
| Output Voltage Fixed | 3.3V |
| Dropout Voltage - Max | 1.3V |
| Output Current - Max | 800mA |
| Tolerance (%) | ±1% |
| Operating Temp Range | -40°C to +125°C |
| Regulator Topology | Fixed |
| Quiescent Current | 5mA |
| No. of Outputs | Single |
| Output Noise | 100µV |
| Load Regulation | 1mV |
| Line Regulation | 1mV |
| Package Style | SOT-223 (TO-261-4, SC-73) |
| Mounting Method | Surface Mount |
Key Features
- Low dropout voltage (1 V typical)
- Output current up to 800 mA
- Fixed output voltage of 3.3V, with other fixed versions available (1.2V, 1.8V, 2.5V, 3.0V, 5.0V)
- Adjustable version availability (VREF = 1.25 V)
- Internal current and thermal limit
- Output voltage tolerance within ±1% at 25°C and 2% in full temperature range
- Supply voltage rejection: 75 dB (typical)
- High efficiency assured by NPN pass transistor
- Requires only a 10 µF minimum capacitor for stability
Applications
- Power regulation for low noise circuits
- Power regulation for microcontrollers and other 3.3V devices
- Portable devices requiring LDO regulators and power conservation
- Replacement for non-RoHS 1117 alternatives
- SCSI-2 active termination (for the 2.85V version)
Q & A
- What is the LD1117S33CTR?
The LD1117S33CTR is a fixed low drop positive voltage regulator with a fixed output voltage of 3.3V and a maximum output current of 800 mA.
- What is the package type of the LD1117S33CTR?
The LD1117S33CTR is packaged in a SOT-223 (TO-261-4, SC-73) surface mount package.
- What is the dropout voltage of the LD1117S33CTR?
The dropout voltage of the LD1117S33CTR is 1.3V maximum.
- What is the operating temperature range of the LD1117S33CTR?
The operating temperature range is -40°C to +125°C.
- What is the quiescent current of the LD1117S33CTR?
The quiescent current is 5 mA.
- What type of transistor is used in the LD1117S33CTR?
The LD1117S33CTR uses an NPN pass transistor.
- What is the output noise of the LD1117S33CTR?
The output noise is 100 µV.
- What is the load regulation of the LD1117S33CTR?
The load regulation is 1 mV.
- What is the line regulation of the LD1117S33CTR?
The line regulation is 1 mV.
- What capacitor is required for stability?
A minimum 10 µF capacitor is required for stability.
