NAND-gate Latch
The time sequence at right shows the conditions under which the set and reset inputs cause a state change, and when they don't. The concept of a "latch" circuit is important to creating memory devices. The function of such a circuit is to "latch" the value created by the input signal to the device and hold that value until some other signal changes it. | 
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| Set-reset Flip-flop | NOR-gate Latch |
| To Clocked Version | NAND Gate |
| Application in D Flip-flop |
Electronics concepts
Digital circuits
| HyperPhysics*****Electricity and magnetism | R Nave |
which does not switch the flip-flop, so it ignores further input. 