Overview
The TL431QPK is a three-pin adjustable precision shunt regulator produced by Texas Instruments. It is designed to offer specified thermal stability over a wide range of temperatures, making it suitable for automotive, commercial, and military applications. The device allows for adjustable output voltage settings between approximately 2.5 V and 36 V using two external resistors. This flexibility, combined with its low output impedance and sharp turn-on characteristic, makes the TL431QPK an excellent replacement for Zener diodes in various power supply and regulation applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Reference Voltage (VREF) | 2.44 | 2.495 | 2.55 | V |
| Output Voltage Range | 2.5 | - | 36 | V |
| Reference Voltage Tolerance at 25°C | - | 0.5% (B Grade), 1% (A Grade), 2% (Standard Grade) | - | % |
| Typical Temperature Drift | - | 14 mV (Q Temp) | - | mV |
| Output Impedance | - | 0.2 Ω | - | Ω |
| Sink-Current Capability | 1 mA | - | 100 mA | mA |
| Operating Temperature Range | -40°C | - | 125°C | °C |
| Cathode to Anode Voltage (VKA) | - | - | 37 V | V |
| Reference Input Current (IREF) | -0.05 | 2-4 | 10 | mA |
Key Features
- Adjustable output voltage from approximately 2.5 V to 36 V using two external resistors.
- Specified thermal stability over a wide temperature range (-40°C to 125°C), making it suitable for automotive, commercial, and military applications.
- Low output impedance of 0.2 Ω.
- Sink-current capability from 1 mA to 100 mA.
- Sharp turn-on characteristic, making it an excellent replacement for Zener diodes.
- Low output noise.
- Available in various package types, including SOT-23, SOIC, PDIP, and others.
- Reference voltage tolerance options: 0.5% (B Grade), 1% (A Grade), and 2% (Standard Grade) at 25°C.
Applications
- On-board voltage regulation.
- Adjustable power supplies.
- Switching power supplies.
- Comparator circuits.
- Temperature sensors.
- Voltage clamps.
- Error amplifiers.
- Switch Mode Power Supplies (SMPS).
Q & A
- What is the adjustable output voltage range of the TL431QPK?
The output voltage can be set to any value between approximately 2.5 V and 36 V using two external resistors.
- What are the reference voltage tolerance options for the TL431QPK?
The reference voltage tolerance options are 0.5% (B Grade), 1% (A Grade), and 2% (Standard Grade) at 25°C.
- What is the typical output impedance of the TL431QPK?
The typical output impedance is 0.2 Ω.
- What is the sink-current capability of the TL431QPK?
The sink-current capability ranges from 1 mA to 100 mA.
- What is the operating temperature range of the TL431QPK?
The operating temperature range is from -40°C to 125°C.
- Can the TL431QPK replace Zener diodes in some applications?
- What are some common applications of the TL431QPK?
- What are the different package types available for the TL431QPK?
- Does the TL431QPK have low output noise?
- Is the TL431QPK suitable for automotive applications?
