The TL1431-EP device is a precision-programmable reference with specified thermal stability over the military temperature range. The output voltage can be set to any value from VI(ref) (approximately 2.5 V) to 36 V with two external resistors (see ). This device has a typical output impedance of 0.2 Ω. Active output circuitry provides a very sharp turnon characteristic, making the device an excellent replacement for Zener diodes and other types of references in applications such as onboard regulation, adjustable power supplies, and switching power supplies.