The TL431LI device is a three-terminal adjustable shunt regulator, with specified thermal
stability over applicable automotive, commercial, and military temperature ranges. The output
voltage can be set to any value between Vref (approximately 2.495 V) and 36
V, with two external resistors. These devices have a typical output impedance of 0.3 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. This device is a pin-to-pin alternative to the industry
standard TL431, with optimized Iref and IIdev
performance. The lower Iref and IIdev values enable
designers to achieve higher system accuracy and lower leakage current. The TL432LI device has
exactly the same functionality and electrical specifications as the TL431LI device, but has a
different pinout for the DBZ package.
The TL431LI device is offered in two grades, with initial tolerances (at 25°C) of 0.5%
and 1%, for the B and A grade, respectively. In addition, low output drift versus temperature
ensures good stability over the entire temperature range.
The TL43xLIxQ devices are characterized for operation from –40°C to 125°C.