1 Features

• Reference voltage tolerance at 25°C

– 0.5 (B grade)

– 1 (A grade)

– 2 (Standard grade)

• Adjustable output voltage: Vref to 36 V

• Operation from −40°C to 125°C

• Typical temperature drift (TL43xB)

– 6 mV (C temp)

– 14 mV (I temp, Q temp)

• Low Output Noise

• 0.2-Ω Typical output impedance

• Sink-current capability: 1 mA to 100 mA

2 Applications

• Adjustable voltage and current referencing

• Secondary side regulation in flyback SMPSs

• Zener replacement

• Voltage monitoring

• Comparator with integrated reference

3 Description

The TL431LI / TL432LI are pin-to-pin alternatives

to TL431 / TL432. TL43xLI offers better stability,

lower temperature drift (VI(dev)), and lower

reference current (Iref) for improved system

accuracy.

The TL431 and TL432 devices are three-terminal

adjustable shunt regulators, with specified thermal

stability over applicable automotive, commercial, and

military temperature ranges. The output voltage can

be set to any value between Vref (approximately

2.5 V) and 36 V, with two external resistors.

These devices have a typical output impedance

of 0.2 Ω. Active output circuitry provides a very

sharp turn-on characteristic, making these devices

excellent replacements for Zener diodes in many

applications, such as onboard regulation, adjustable

power supplies, and switching power supplies. The

TL432 device has exactly the same functionality and

electrical specifications as the TL431 device, but has

different pinouts for the DBV, DBZ, and PK packages.

Both the TL431 and TL432 devices are offered in

three grades, with initial tolerances (at 25°C) of

0.5, 1, and 2, for the B, A, and standard

grade, respectively. In addition, low output drift versus

temperature ensures good stability over the entire

temperature range.

The TL43xxC devices are characterized for operation

from 0°C to 70°C, the TL43xxI devices are

characterized for operation from –40°C to 85°C, and

the TL43xxQ devices are characterized for operation

from –40°C to 125°C.

TL431IPKG3属于集成电路（IC） > 电压基准。美国德州仪器公司制造生产的TL431IPKG3电压基准产品属于基准电压源系列，可通过相对较不稳定的电源提供稳定的电势，电压值始终保持恒定，以便在测量、控制和类似应用中用作比较的标准。其功能行为可能与用于大功率调节的线性稳压器相似，但基准电压源器件却不适合用于此类用途。用作比较标准时，若输出电流容量或实际负载电流增大，其性能通常会降低。