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Contents

README

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TL431BQPK

Texas Instruments · Voltage Reference · SOT-89-3

TL431BQPK from Texas Instruments, in a SOT-89-3. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 REF input Reference input pin; establishes the threshold voltage for the internal 2.5V reference and receives feedback for voltage programming.
2 ANODE power_in Anode or common pin; typically connected to ground or return path; internally attached to substrate.
3 CATHODE bidirectional Cathode output pin; serves as the shunt regulator output terminal and sinks cathode current from 1 mA to 100 mA.

Key specifications

Parameter Value
Manufacturer Texas Instruments
Package SOT-89-3
Category Power Management (PMIC)
Pins 3

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
基准电压 (Reference voltage), TL431BQ Vref 2483 2495 2507 mV VKA = Vref,IKA = 10mA 15
整个温度范围内的基准输入电压偏差 (Reference input voltage deviation over temperature range) VI(dev) 14 34 mV VKA = Vref,IKA = 10mA 15
基准电压变化与阴极电压变化之比 (Change in Vref to change in VKA ratio) ΔVref / ΔVKA -1.4 -2.7 mV/V IKA = 10mA,ΔVKA = 10V - Vref 15
基准电压变化与阴极电压变化之比 (Change in Vref to change in VKA ratio) ΔVref / ΔVKA -1 -2 mV/V IKA = 10mA,ΔVKA = 36V - 10V 15
基准输入电流 (Reference input current) Iref 2 4 µA IKA = 10mA,R1 = 10kΩ,R2 = ∞ 15
整个温度范围内的基准输入电流偏差 (Reference input current deviation over temperature range) II(dev) 0.8 2.5 µA IKA = 10mA,R1 = 10kΩ,R2 = ∞ 15
调节的最小阴极电流 (Minimum cathode current for regulation) Imin 0.4 0.7 mA VKA = Vref 15
关闭状态阴极电流 (Off-state cathode current) Ioff 0.1 0.5 µA VKA = 36V,Vref = 0 15
动态阻抗 (Dynamic impedance) /ZKA/ 0.2 0.5 Ω VKA = Vref,f ≤ 1kHz,IKA = 1mA 至 100mA 15
阴极电压 (Cathode voltage) VKA 36 V Minimum printed as Vref (symbol, no numeric value given) 6
连续阴极电流范围 (Continuous cathode current range) IKA 1 100 mA 6
自然通风条件下的工作温度范围 (Operating free-air temperature range) TA -40 125 °C TL43xxQ 6
阴极电压 (Cathode voltage) VKA 37 V 6
连续阴极电流范围 (Continuous cathode current range) IKA -100 150 mA 6
基准输入电流 (Reference input current) II(ref) -0.05 10 mA 6
工作结温范围 (Operating virtual junction temperature range) TJ 150 °C 6
贮存温度范围 (Storage temperature range) Tstg -65 150 °C 6
结至环境热阻 (Junction-to-ambient thermal resistance) RθJA 52 °C/W PK package column 6
结至外壳(顶部)热阻 (Junction-to-case (top) thermal resistance) RθJC(top) 9 °C/W PK package column 6

CAD (KiCad official)

  • Symbol: TL431BQPK
  • Footprint: Package_TO_SOT_SMD:SOT-89-3
  • 3D model: SOT-89-3 (KiCad packages3D, STEP)
  • 3D model files: tl431bqpk-etched.step / tl431bqpk-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); tl431bqpk.step / tl431bqpk.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (86 pp, sha256 313277b9351e61ed, retrieved 2026-09-22, tier: lcsc)
  • Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
  • Extractor: parts-factory 2.0.0 / extract_pins 0.2, primary claude-haiku-4-5-20251001 (text), consensus claude-sonnet-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF