2/24/2008 9T6WP
BCM7405
Preliminary Hardware Data Module
Timing and AC Characteristics
06/29/07
Bro a d c o m C o rp o r a ti o n
Page 1-166
ITU656 Output Timing
Document
7405-1HDM00-R
ITU656 O
UTPUT
T
IMING
Figure 1-51: ITU656 Output Timing Diagram
The clock signal is a 27-MHz square wave. The positive transition of the clock signal occurs midway between data
transitions.
•
Clock period: T = 37 ns
•
Clock pulse width: t = 18.5 ns
•
Data timing – sending end: t
d
= 18.5 ± 3 ns, based on the ITU-R_BT656-4 specification.
T
IMING
F
OR
ITU656 O
UTPUT
AT
VO
_656 P
INS
Table 1-36: Timing for ITU656 Output at vo_656 Pins
Pin
Timing (td) Min
Timing (td) Max
vo_656_0
18.118 ns
18.826 ns
vo_656_1
18.162 ns
19.118 ns
vo_656_2
18.186 ns
18.863 ns
vo_656_3
18.111 ns
19.210 ns
vo_656_4
18.160 ns
18.812 ns
vo_656_5
18.148 ns
18.975 ns
vo_656_6
18.078 ns
18.994 ns
vo_656_7
18.200 ns
19.054 ns