Noise Elimination Operation Example - NEC PD789488 User Manual

CHAPTER 15 REMOTE CONTROLLER RECEIVER (
Clock
RIN (ideal)
L
Noise
RIN
Synchronization
samp1
samp2
L
Internal RIN
L
Delayed by 2 to 3 clocks
Remark Internal RIN is a signal after synchronization and sampling are performed twice, and is therefore later
than the actual signal input from the outside to the RIN pin by two to three clocks.
Clock
Clock RIN (ideal)
L
Noise
RIN
Synchronization
samp1
samp2
samp3
L
Internal RIN
L
Remark Internal RIN is a signal after synchronization and sampling are performed three times, and is therefore
later than the actual signal input from the outside to the RIN pin by 3 to 4 clocks.
288
Figure 15-8. Noise Elimination Operation Example (1/2)
(a) 1-clock noise elimination (PRSEN = 0, NCW = 0)
L
H
(b) 2-clock noise elimination (PRSEN = 0, NCW = 1)
H
L
H
H
Delayed by 3 to 4 clocks
User's Manual U15331EJ4V1UD
µ
PD789489, 78F9489 ONLY)
Since synchronized signal = samp1 = H is not satisfied, samp1 is not latched.
Since synchronized signal = samp1 = H, samp1 is latched from this
point and later.
Since synchronized signal = samp2 = H is not satisfied, samp2 is
not latched.