DIY SR Latch Out of Transistors

An SR latch is a kind of circuit that is called “bistable.” Bistable circuits have two stable states, hence the name BI-stable. One of the simpler versions of this kind of circuit is the SR latch, which stands for “Set/Reset Latch.” The SR latch is most notably used for memory, because after you select a value, it is ‘latched’ so if there is no change in input, or the inputs turn off, the outputs stay the same.”

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