Overview
The LM317MDCYRG3 is an adjustable 3-terminal positive voltage regulator produced by Texas Instruments. This device is capable of supplying more than 500 mA over an output voltage range of 1.25 V to 37 V. It is exceptionally easy to use and requires only two external resistors to set the output voltage. The LM317MDCYRG3 features internal current limiting, thermal-overload protection, and safe-area compensation, making it highly reliable and robust. The regulator is designed to operate from an input voltage supply range between 2.5 V and 40 V greater than the output voltage, with a minimum headroom of 2.5 V required for proper operation.
Key Specifications
| Parameter | Minimum | Maximum | Unit |
|---|---|---|---|
| Output Voltage Range | 1.25 | 37 | V |
| Output Current | 0.01 | 0.5 | A |
| Input-to-Output Differential Voltage | 2.5 | 40 | V |
| Operating Junction Temperature | -40 | 125 | °C |
| Storage Temperature Range | -65 | 150 | °C |
| Ripple Rejection (VO = 10 V, f = 120 Hz) | 65 | 80 | dB |
| Long-term Stability (TJ = 25°C) | 0.3 | 1.0 | %/1k hrs |
| Thermal Shutdown | - | 180 | °C |
Key Features
- Adjustable output voltage range from 1.25 V to 37 V.
- Output current greater than 500 mA.
- Internal short-circuit current limiting and thermal-overload protection.
- Safe-area compensation for reliable operation.
- High line and load regulation performance.
- No ground terminal; quiescent current flows to the load instead of ground.
- Optional use as a floating current source controlled by a single resistor.
- High ripple-rejection ratios achievable with an adjustment terminal capacitor.
Applications
- Electronic point-of-sale systems.
- Medical and health/fitness applications.
- Printers and appliances/white goods.
- TV and set-top box applications.
- Local, on-card regulation in various electronic systems.
- Adjustable switching regulators and programmable output regulators.
- Precision current regulators by connecting a fixed resistor between the adjustment and output terminals.
Q & A
- What is the output voltage range of the LM317MDCYRG3?
The output voltage range is adjustable from 1.25 V to 37 V.
- What is the maximum output current of the LM317MDCYRG3?
The maximum output current is greater than 500 mA.
- What are the key protection features of the LM317MDCYRG3?
The device features internal short-circuit current limiting, thermal-overload protection, and safe-area compensation.
- How do you set the output voltage of the LM317MDCYRG3?
The output voltage is set using two external resistors according to the formula Vout = Vref × (1 + R2/R1) + Iadj × R2.
- What is the minimum headroom required for the LM317MDCYRG3 to operate?
A minimum headroom of 2.5 V is required between the input and output voltages.
- Can the LM317MDCYRG3 be used as a current source?
Yes, it can be used as a floating current source controlled by a single resistor.
- What is the thermal shutdown temperature of the LM317MDCYRG3?
The thermal shutdown temperature is approximately 180°C.
- How does the LM317MDCYRG3 improve ripple rejection?
Ripple rejection can be improved by using an adjustment terminal capacitor.
- What are some common applications of the LM317MDCYRG3?
Common applications include electronic point-of-sale systems, medical and health/fitness applications, printers, appliances, and TV/set-top box applications.
- What is the storage temperature range for the LM317MDCYRG3?
The storage temperature range is from -65°C to 150°C.
