Overview
The TLV431BIDBZRG4 is a low-voltage adjustable precision shunt regulator produced by Texas Instruments. This device is part of the TLV431 series, known for its low-voltage operation and adjustable output voltage. The TLV431BIDBZRG4 operates with a reference voltage (VREF) of 1.24V and can be adjusted to output voltages between 1.24V and 6V using two external resistors. It is particularly useful in applications requiring low-voltage adjustability and high precision, such as in industrial, automotive, telecommunications, and computing systems.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Reference Voltage (VREF) | 1.234 | 1.24 | 1.246 | V |
| Reference Voltage Deviation (VREF(dev)) | 4 | - | 12 | mV |
| Minimum Cathode Current (IK(min)) | 55 | - | 100 | µA |
| Off-State Cathode Current (IK(off)) | 0.001 | - | 0.1 | µA |
| Dynamic Impedance (|zKA|) | 0.25 | - | 0.4 | Ω |
| Operating Temperature Range | -40°C to 85°C | - | - | - |
| Package Type | SOT-23-3 | - | - | - |
Key Features
- Low-voltage operation with a reference voltage (VREF) of 1.24V
- Adjustable output voltage from VREF to 6V using two external resistors
- High precision with reference voltage tolerances of 0.5% at 25°C for the TLV431B version
- Low minimum cathode current (IK(min)) of 55µA to 100µA
- Low dynamic impedance of 0.25Ω to 0.4Ω
- Operates over a wide temperature range: -40°C to 85°C for the TLV431BI version
- Compact SOT-23-3 package suitable for power and space-sensitive applications
- Internal amplifier and reference, allowing it to function as a shunt regulator, error amplifier, or comparator with integrated reference
Applications
- Secondary side regulation in flyback switching-mode power supplies (SMPS)
- Zener diode replacement in many applications, including on-board regulation and adjustable power supplies
- Voltage monitoring and regulation in industrial, automotive, telecommunications, and computing systems
- Isolated feedback circuits for 3V to 3.3V switching-mode power supplies when used with an optocoupler
- Comparator applications requiring a precise reference voltage
Q & A
- What is the reference voltage (VREF) of the TLV431BIDBZRG4?
The reference voltage (VREF) is 1.24V.
- What is the adjustable output voltage range of the TLV431BIDBZRG4?
The output voltage can be adjusted from 1.24V to 6V using two external resistors.
- What is the minimum cathode current required for regulation?
The minimum cathode current (IK(min)) is 55µA to 100µA.
- What is the dynamic impedance of the TLV431BIDBZRG4?
The dynamic impedance is 0.25Ω to 0.4Ω.
- What are the typical applications of the TLV431BIDBZRG4?
Typical applications include secondary side regulation in SMPS, Zener diode replacement, voltage monitoring, and comparator applications.
- What is the operating temperature range of the TLV431BI version?
The operating temperature range is -40°C to 85°C.
- What package type is the TLV431BIDBZRG4 available in?
The device is available in a SOT-23-3 package.
- Can the TLV431BIDBZRG4 be used as a comparator?
Yes, it can be used as a comparator with integrated reference.
- How does the TLV431BIDBZRG4 behave in closed-loop operation?
In closed-loop operation, the device behaves as an error amplifier, regulating the output voltage to match the internal reference voltage.
- What is the significance of the reference pin in the TLV431BIDBZRG4?
The reference pin requires a minimum current (Iref ≥ 0.5µA) and cannot be left floating; it is driven into an NPN transistor requiring a base current to operate properly.
