User manual

Kontron Compact Computers AG SMX945 Detailed Manual V1.1
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The module's transmit and receive insertion-loss budgets are different due to the presence of the coupling
caps in the module transmit path. The module transmit path insertion-loss budget shall be 4.65 dB (3.46 dB
+ 1.19 dB). The module receive-path insertion-loss budget shall be 3.46 dB. COM Express™ connector loss
is accounted for separately.
The carrier board's transmit and receive insertion-loss budgets are different due to the presence of the
coupling caps in the carrier board transmit path. The carrier board transmit path insertion-loss budget shall
be 9.49 dB (8.30 dB + 1.19 dB). The carrier board receive path insertion-loss shall be 8.30 dB. COM
Express™ connector loss is accounted for separately.
Signal Description I/O Termination Remarks
AC_RST# CODEC Reset O 3.3V
AC_SYN Serial Bus Synchronization O 3.3V AC_SYNC is a boot strap
AC_SYNC is a boot strap
AC_BIT_CLK 12.228MHz Serial Bit Clock
from CODEC
O 3.3V
AC_SDOUT Audio Serial Data Output to
CODEC
O 3.3V AC_SDOUT is a boot strap signal
(see note below)
AC_SDIN[0-2] Audio Serial Data Input from
CODEC0-CODEC2
I 3.3V Only AC_SDIN2 is PD 10k
Note...
Not available: CODECDISABLE Disable onboard Audio Codec I 3.3V PD 10k