Cirrus Logic CRD4202-1 - Manual (Page 15)

CRD4202-1
DS549RD1A1 15
U7
TC7SZ125FU
5
1
2 4
3
U8
TC7SZ126FU
5 1
2 4
3
C70
0.1uF
X7R
C71
0.1uF
X7R
R54
1K
+3.3VD
DGND
DGND
+3.3VD
PRIM_DN#
ASDIN1
ASDIN0 ASDIN
R54 = 1K forces
motherboard codec(s)
to be held in RESET
DO NOT use this circuit for motherboard designs. This circuit is strictly for CNR cards.
Replace R54 with 100K for automatic demotion
when used with primary motherboard codec(s).
For motherboard designs:
connect ASDIN to ASDIN0 if primary codec,
connect ASDIN to ASDIN1 if secondary codec.
Figure 9. Auto Demotion and Serial Buffers