TL431A 36V 100mA Adjustable Precision Shunt Regulator TO-92

TL431A 36V 100mA Adjustable Precision Shunt Regulator TO-92 is a programmable voltage reference used in precision regulation, voltage monitoring, and power management circuits. It acts like a low-voltage adjustable Zener diode with a sharp turn-on characteristic and is ideal for linear regulators, switching power supplies, and error amplifiers.

Key Features:

• Adjustable Output: Programmable from 2.5V to 36V with two external resistors
• High Stability: Precise 2.495V reference with ±1% initial accuracy
• Low Dynamic Impedance: Improves regulation performance across load variations
• Wide Operating Current: Supports 1mA to 100mA cathode current
• Low Temperature Drift: Excellent thermal stability for sensitive applications

Technical Specifications:

• Reference Voltage: 2.495V ±1%
• Adjustable Range: 2.5V to 36V
• Cathode Current: 1mA to 100mA
• Output Impedance: Typically 0.2Ω
• Temperature Coefficient: 50ppm/°C typical
• Output Voltage Tolerance: ±1% (TL431A grade)

Mechanical Specifications:

• Package Type: TO-92 (Through-hole)
• Material: Epoxy molded plastic
• Pin Count: 3
• Mounting Type: Through-hole vertical mount

Dimensions:

• Body Width: ~4.5mm
• Body Height: ~4.2mm
• Lead Pitch: 1.27mm (standard TO-92 spacing)
• Lead Length: ~12mm

Pinout and Wiring:

• Pin 1 (Reference): Connect to resistor divider for adjustable voltage
• Pin 2 (Anode): Ground terminal or return path
• Pin 3 (Cathode): Output regulated voltage or connected to load
• Basic Configuration: Acts like a programmable Zener with two resistors

Datasheet Reference:

• Search online for “TL431A datasheet by Texas Instruments or ON Semiconductor”

Applications:

• Switching Power Supplies: Used for output feedback and voltage sensing
• Battery Chargers: Acts as precision reference for regulation
• Precision Regulators: Voltage control in analog designs
• Microcontroller Circuits: Reference source or voltage monitor
• Adjustable Voltage References: Custom reference generation with resistor divider

Equivalent Models:

• LM431: Functionally equivalent adjustable shunt regulator
• KA431: Similar 3-terminal programmable precision regulator
• AS431: Accurate shunt reference with same pinout
• TL431ACZ: Tighter tolerance version in TO-92 package

Package Includes:

• 1 x TL431A Adjustable Precision Shunt Regulator TO-92