Overview
The LM217D2T, part of the LM217 and LM317 series, is a monolithic integrated circuit designed by STMicroelectronics. It is a positive adjustable voltage regulator available in various packages, including the D²PAK package for the LM217D2T. This regulator is capable of supplying more than 1.5 A of load current with an output voltage adjustable over a range of 1.2 to 37 V. The device is known for its ease of use, high accuracy, and comprehensive protection features such as current limiting, thermal shutdown, and Safe Operating Area (SOA) control.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Output Voltage Range | 1.2 to 37 | V |
| Output Current | Internally limited, up to 1.5 A | A |
| Line Regulation | 0.01 to 0.05 %/V | %/V |
| Load Regulation | 5 to 50 mV (VO ≤ 5 V), 0.1 to 1% (VO ≥ 5 V) | mV, % |
| Adjustment Pin Current | 50 to 100 µA | µA |
| Reference Voltage | 1.2 to 1.3 V | V |
| Minimum Load Current | 3.5 to 10 mA | mA |
| Maximum Load Current | 1.5 to 2.2 A | A |
| Operating Junction Temperature | -25 to 150 °C | °C |
| Thermal Resistance Junction-Ambient | 62.5 °C/W (D²PAK) | °C/W |
Key Features
- Adjustable Output Voltage: The output voltage can be adjusted over a range of 1.2 to 37 V using an external resistive divider.
- High Current Capability: Capable of supplying more than 1.5 A of load current.
- Precision Regulation: Offers 0.1% line and load regulation, ensuring stable output voltage.
- Comprehensive Protection: Includes current limiting, thermal shutdown, and SOA control for enhanced reliability.
- Floating Operation: Can regulate high voltage supplies relative to ground as long as the maximum input-to-output differential is not exceeded.
- Low Noise and Ripple Rejection: Features low output noise voltage and high supply voltage rejection.
Applications
- Power Supplies: Ideal for use in adjustable power supplies where high current and precision voltage regulation are required.
- Current Regulation: Can be used as a precision current regulator by connecting a fixed resistor between the adjustment and output pins.
- Battery Chargers: Suitable for battery charging applications with adjustable output voltage and current limiting.
- Electronic Shutdown Regulators: Can be configured for electronic shutdown applications with precise voltage control.
- High Voltage Regulation: Useful in systems requiring regulation of high voltage supplies relative to ground.
Q & A
- What is the output voltage range of the LM217D2T?
The output voltage range is adjustable from 1.2 to 37 V.
- What is the maximum output current of the LM217D2T?
The maximum output current is internally limited, up to 1.5 A.
- What are the key protection features of the LM217D2T?
The device includes current limiting, thermal shutdown, and Safe Operating Area (SOA) control.
- How is the output voltage adjusted in the LM217D2T?
The output voltage is adjusted using an external resistive divider connected to the adjustment pin.
- What is the typical adjustment pin current of the LM217D2T?
The typical adjustment pin current is 50 to 100 µA.
- What is the reference voltage of the LM217D2T?
The reference voltage is between 1.2 and 1.3 V.
- What are the recommended external capacitors for the LM217D2T?
Recommended capacitors include an input bypass capacitor of 0.1 µF, an adjustment terminal to ground 10 µF capacitor, and an output capacitor of 1 µF tantalum or 25 µF aluminum electrolytic.
- Can the LM217D2T be used as a current regulator?
Yes, it can be used as a precision current regulator by connecting a fixed resistor between the adjustment and output pins.
- What are the thermal considerations for the LM217D2T?
The thermal resistance junction-ambient for the D²PAK package is 62.5 °C/W.
- What is the operating junction temperature range for the LM217D2T?
The operating junction temperature range is -25 to 150 °C.
