Solve SR Latch Problem: Draw NAND Gates, Derive Table, Show Timing

[snoggerT]

-NOTE: I figured the problem out. Please ignore.

Draw a similar latch using NAND gates (from one using NOR gates). Derive its characteristic table and show its timing diagram, given the R and S inputs.

S R Qa Qb
------------
0 0 0/1 1/0 (no change)
0 1 0 1
1 0 1 0
1 1 0 0

The Attempt at a Solution

I just replaced the NOR gates with NAND gates and did the characteristic diagram. Though the solution in the book complements the S and R inputs and switches the Qa and Qb outputs. I'm not sure why they do this, but can only assume by "similar" they mean to draw using NAND gates and have the same outputs as the NOR gate latch. So is there is a reason why you would complement the inputs and switch the outputs? If I need to scan in the circuit drawing, please let me know.

 

[LightHero]

The NAND gate latch looks like this: S | R | Qa | Qb------0 | 0 | 1/0 | 0/1 (no change)0 | 1 | 1 | 01 | 0 | 0 | 11 | 1 | 1 | 1

 

[piercas]

it is important to understand the reasoning behind any changes or modifications made to a circuit design. In this case, it is likely that the reason for complementing the inputs and switching the outputs is to maintain the same functionality as the original NOR gate latch.

By complementing the inputs, the NAND gate latch will behave in the same way as the NOR gate latch, with a logic 0 input causing the output to be a logic 1 and vice versa. This ensures that the latch will still function as a memory element, storing the previous state until a new input is received.

Switching the outputs may also be necessary to maintain the same functionality. Since the NAND gate is an inverted version of the NOR gate, the outputs will also be inverted. By switching the outputs, the NAND gate latch will have the same output as the NOR gate latch, ensuring that the overall circuit behaves in the same way.

In summary, complementing the inputs and switching the outputs in the NAND gate latch is likely done to maintain the same functionality as the NOR gate latch. This ensures that the circuit operates as intended and any changes made do not affect the overall behavior of the latch.