MAX807 watchdog for microcontroller systems

Microcontrollers are used in ever-increasing numbers, not only in technical and engineering applications, but also in domestic products and motor vehicles. This proliferation makes increased demands on the operational safety of microcontroller systems. After all, their failure may damage or even destroy the equipment they are used in. Even worse, such failure may create a danger to the health or the life of the operator.Two examples serve to illustrate the risks ensuing in an equipment against which the microcontroller must be protected.Semiconductor producers guarantee error-free operation of their microcontrollers when the supply voltage is 5 V ±10%. Overvoltages are readily negated by the use of appropriate regulation of the supply lines. When, however, for whatever reason the supply voltage drops below 4.5 V, the reaction of the microcontroller cannot be foreseen.