Транзисторы - программируемый однопереходный

Programmable unijunction transistors (PUTs) are a relative of Silicon Controlled Rectifier (SCR) devices, having a characteristic behavior somewhat like a unidirectional DIAC with a user-configurable threshold voltage. While useful for creating low frequency oscillator and timing functions, SCR triggering applications, and others, alternative techniques for addressing such needs have gained greater favor.