Overview
The LD1117STR, produced by STMicroelectronics, is a low drop voltage regulator that offers high efficiency and reliability in a variety of applications. This regulator is available in both fixed and adjustable output voltage versions, making it versatile for different use cases. The fixed output versions provide voltages of 1.2 V, 1.8 V, 2.5 V, 3.3 V, and 5.0 V, while the adjustable version allows for customization based on the reference voltage (VREF = 1.25 V).
Key Specifications
| Parameter | Test Condition | Min. | Max. | Unit | |
|---|---|---|---|---|---|
| Output Current (IO) | Vin = 6.8 V, TJ = 25 °C | 800 | 950 | 1300 | mA |
| Dropout Voltage (Vd) | IO = 100 mA | 1 | 1.1 | 1.1 | V |
| Dropout Voltage (Vd) | IO = 500 mA | 1.05 | 1.15 | 1.15 | V |
| Dropout Voltage (Vd) | IO = 800 mA | 1.10 | 1.2 | 1.2 | V |
| Line Regulation (∆VO) | Vin - VO = 1.5 to 13.75 V, IO = 10 mA | 0.035 | 0.2 | 0.2 | % |
| Load Regulation (∆VO) | Vin - VO = 3 V, IO = 10 to 800 mA | 0.1 | 0.4 | 0.4 | % |
| Temperature Stability (∆VO) | TJ = 0 to 125 °C | 0.5 | % | ||
| Supply Voltage Rejection (SVR) | IO = 40 mA, f = 120 Hz, TJ = 25 °C | 60 | 75 | dB | |
| Quiescent Current (Id) | Vin ≤ 8 V | 5 | 10 | mA | |
| Output Noise Voltage (eN) | B = 10 Hz to 10 kHz, TJ = 25 °C | 100 | µV |
Key Features
- Low Dropout Voltage: Typically 1 V, ensuring high efficiency in applications where voltage supply is critical.
- High Output Current: Up to 800 mA, making it suitable for a wide range of applications.
- Fixed and Adjustable Output Voltages: Fixed versions offer 1.2 V, 1.8 V, 2.5 V, 3.3 V, and 5.0 V, while the adjustable version uses a reference voltage (VREF = 1.25 V).
- NPN Pass Transistor: Ensures high efficiency as the quiescent current flows mostly into the load.
- Tight Output Voltage Tolerance: Within ± 1% at 25 °C due to on-chip trimming.
- Stability with Minimal Capacitance: Stability is easily achieved with a common 10 µF capacitor.
- Internal Current and Thermal Limit: Provides protection against overcurrent and overheating.
- High Supply Voltage Rejection: Up to 75 dB, ensuring minimal noise impact from the input voltage.
Applications
The LD1117STR is versatile and can be used in a variety of applications, including:
- Power Supplies: For providing stable output voltages in power supply units.
- Embedded Systems: In microcontroller-based systems where stable voltage is crucial.
- Automotive Electronics: Due to its robust performance over a wide temperature range.
- Industrial Control Systems: Where reliable voltage regulation is essential.
- Consumer Electronics: In devices requiring stable and efficient voltage regulation.
Q & A
- What is the maximum output current of the LD1117STR?
The LD1117STR can provide up to 800 mA of output current.
- What are the available fixed output voltages for the LD1117STR?
The fixed output voltages available are 1.2 V, 1.8 V, 2.5 V, 3.3 V, and 5.0 V.
- What is the typical dropout voltage of the LD1117STR?
The typical dropout voltage is 1 V.
- What type of transistor is used in the LD1117STR?
The LD1117STR uses an NPN pass transistor, which ensures high efficiency.
- What is the minimum capacitance required for stability?
A minimum of 10 µF capacitor is required for stability.
- What is the output voltage tolerance at 25 °C?
The output voltage tolerance is within ± 1% at 25 °C.
- What is the supply voltage rejection of the LD1117STR?
The supply voltage rejection is up to 75 dB.
- What are the package options for the LD1117STR?
The LD1117STR is available in SOT-223, DPAK, SO-8, and TO-220 packages.
- What is the operating input voltage range for the LD1117STR?
The operating input voltage range is up to 15 V.
- What is the quiescent current of the LD1117STR?
The quiescent current is typically 5 to 10 mA.
