Overview
The LM317EMPX/EMSN is part of the LM317-N series of adjustable 3-pin positive voltage regulators produced by Texas Instruments (originally developed by National Semiconductor). These regulators are known for their ease of use and robust performance, capable of supplying up to 1.5 A of output current over a wide output voltage range of 1.25 V to 37 V.
The LM317EMPX/EMSN is particularly versatile, requiring only two external resistors to set the desired output voltage. It offers excellent line and load regulation, making it superior to standard fixed regulators. The device also features full overload protection, including current limit, thermal overload protection, and safe area protection, ensuring reliable operation even under adverse conditions.
Key Specifications
| Parameter | Value |
|---|---|
| Output Voltage Range | 1.25 V to 37 V |
| Output Current | Up to 1.5 A |
| Input Voltage - Min | 4.2 V |
| Output Type | Adjustable |
| Operating Temperature Range | 0°C to 125°C |
| Package Type | SOT-223 (DCY) |
| Number of Pins | 4 |
| Polarity | Positive |
Key Features
- Typical 0.1% load regulation and 0.01%/V line regulation.
- Adjustable output voltage down to 1.25 V.
- Current limit constant with temperature.
- 80-dB ripple rejection.
- Short-circuit protected output.
- No external capacitors needed unless the device is more than 6 inches from the input filter capacitors.
- Optional output capacitor for improved transient response.
- Adjustment terminal can be bypassed for high ripple rejection ratios.
- Can be used as a precision current regulator by connecting a fixed resistor between the adjustment pin and output.
Applications
The LM317EMPX/EMSN is suitable for a wide range of applications requiring adjustable voltage regulation, including:
- Power supplies for electronic equipment.
- Battery chargers and power management systems.
- Industrial control systems.
- Aerospace and defense electronics.
- Automotive electronics.
Q & A
- What is the output voltage range of the LM317EMPX/EMSN?
The output voltage range is from 1.25 V to 37 V.
- What is the maximum output current of the LM317EMPX/EMSN?
The maximum output current is up to 1.5 A.
- What is the minimum input voltage required for the LM317EMPX/EMSN?
The minimum input voltage is 4.2 V.
- Does the LM317EMPX/EMSN require external capacitors?
No external capacitors are needed unless the device is more than 6 inches from the input filter capacitors.
- What is the operating temperature range of the LM317EMPX/EMSN?
The operating temperature range is from 0°C to 125°C.
- Can the LM317EMPX/EMSN be used as a current regulator?
Yes, it can be used as a precision current regulator by connecting a fixed resistor between the adjustment pin and output.
- What kind of overload protection does the LM317EMPX/EMSN offer?
The device offers full overload protection, including current limit, thermal overload protection, and safe area protection.
- How can I improve the ripple rejection of the LM317EMPX/EMSN?
The ripple rejection can be improved by bypassing the adjustment terminal.
- What package type is the LM317EMPX/EMSN available in?
The device is available in the SOT-223 (DCY) package.
- What are some common applications of the LM317EMPX/EMSN?
Common applications include power supplies, battery chargers, industrial control systems, aerospace and defense electronics, and automotive electronics.
