时序逻辑电路
# CMOS
- complementary metal oxide semiconductor
- CMOS technology is used for constructing integrated circuit (IC) chips, including microprocessors, microcontrollers, memory chips (including CMOS BIOS), and other digital logic circuits.
# SR Latch
- S = set
- R = reset
- (S, R) = (0, 0) -> hold(store)
- (S, R) = (0, 1) -> Q = 0
- (S, R) = (1, 0) -> Q = 1
- (S, R) = (1, 1) -> error state
- (S, R) : (1, 0) <=> (0, 0) <=> (0, 1)
- init: R=1, S=0, Q=0, Q’=1
# D Latch
- CLK 表示是否要改变 Q 的值
- D 表示把 Q 设成什么值
- 但因为 not 导致的延迟, 会出现抖动
# D Flip-Flop
- 通过组合两个 D Latch, 确保不会出现 Q 与 D 不符
# Register
- n 个 D flip-flop 组成的结构可以表示 $2^n-1$ 的数字
# Synchronous sequential circuit 同步时序电路
- 对多个 D flip-flop 结构输入同步的 CLK
