Statistics: Posted by Sergey89 — Sun Jan 05, 2014 5:33 pm
Statistics: Posted by AndreyB — Sun Jan 05, 2014 5:30 pm
Statistics: Posted by acab — Tue Dec 24, 2013 5:13 pm
Statistics: Posted by XDA — Tue Dec 24, 2013 5:11 pm
The PNP power transistor used as the pass element in the LP2985-N has an inherent diode connected between
the regulator output and input. During normal operation (where the input voltage is higher than the output) this
diode is reverse-biased).
However, if the output is pulled above the input, this diode will turn ON and current will flow into the regulator
output. In such cases, a parasitic SCR can latch which will allow a high current to flow into VIN (and out the
ground pin), which can damage the part.
Statistics: Posted by Sergey89 — Mon Dec 16, 2013 3:44 pm
Statistics: Posted by frig — Mon Dec 16, 2013 3:38 pm
В LP2985 паразитного диода нет. Там же не ключ, а регулирующий элемент в виде PNP транзистора. Как и в большинстве LDO стабилизаторов.Для LP2985 дана рекомендация по установке внешнего диода шоттки как раз для защиты этого паразитного диода и хотя для LM2674 такой рекомендации нет я не думаю, что выполнение её будем лишним.
Statistics: Posted by Mister Kotleta — Mon Dec 16, 2013 3:32 pm