Si4734/35-C40
28 Rev. 1.0
Table 15. Selected Si473x Properties
Prop Name Description Default
0x1100 FM_DEEMPHASIS Sets de-emphasis time constant. Default is 75 µs. 0x0002
0x1105
FM_BLEND_STEREO_
THRESHOLD
Sets RSSI threshold for stereo blend (full stereo above
threshold, blend below threshold). To force stereo set this to 0.
To force mono set this to 127. Default value is 49 dBµV.
0x0031
0x1106
FM_BLEND_MONO_
THRESHOLD
Sets RSSI threshold for mono blend (full mono below threshold,
blend above threshold). To force stereo, set this to 0. To force
mono, set this to 127. Default value is 30 dBµV.
0x001E
0x1200
FM_RSQ_INT_
SOURCE
Configures interrupt related to RSQ metrics. 0x0000
0x1300 FM_SOFT_MUTE_RATE
Sets the attack and decay rates when entering and leaving soft
mute.
0x0040
0x1302
FM_SOFT_MUTE_
MAX_ATTENUATION
Sets maximum attenuation during soft mute (dB). Set to 0 to
disable soft mute. Default is 16 dB.
0x0010
0x1303
FM_SOFT_MUTE_
SNR_THRESHOLD
Sets SNR threshold to engage soft mute. Default is 4 dB. 0x0004
0x1400
FM_SEEK_BAND_
BOTTOM
Sets the bottom of the FM band for seek. Default is 8750. 0x222E
0x1401 FM_SEEK_BAND_TOP Sets the top of the FM band for seek. Default is 10790. 0x2A26
0x1402
FM_SEEK_FREQ_
SPACING
Selects frequency spacing for FM seek. 0x000A
0x1403
FM_SEEK_TUNE_
SNR_THRESHOLD
Sets the SNR threshold for a valid FM Seek/Tune. Default value
is 3 dB.
0x0003
0x1404
FM_SEEK_TUNE_
RSSI_TRESHOLD
Sets the RSSI threshold for a valid FM Seek/Tune. Default
value is 20 dBuV.
0x0014
0x1500 RDS_INT_SOURCE Configures RDS interrupt behavior. 0x0000
0x1501 RDS_INT_FIFO_COUNT
Sets the minimum number of RDS groups stored in the receive
RDS FIFO required before RDS RECV is set.
0x0000
0x1502 RDS_CONFIG Configures RDS setting. 0x0000
0x3100 AM_DEEMPHASIS
Sets de-emphasis time constant. Can be set to 50 us. De-
emphasis is disabled by default.
0x0000
0x3102 AM_CHANNEL_FILTER
Selects the bandwidth of the channel filter for AM/SW/LW recep-
tion. The choices are 6, 4, 3, 2.5, 2, 1.8, or 1 kHz. In addition, a
power line rejection filter can be applied. The default is the
2 kHz bandwidth filter without power line rejection.
0x0003
0x3103
AM_AUTOMATIC_VOLUME_
CONTROL_MAX_GAIN
Selects the maximum gain for automatic volume control. 0x1543
0x3200 AM_RSQ_INTERRUPTS
Configures interrupt related to RSQ metrics. All interrupts are
disabled by default.
0x0000
0x3300 AM_SOFT_MUTE_RATE
Sets the rate of attack when entering or leaving soft mute. The
default is 278 dB/s.
0x0040
0x3302
AM_SOFT_MUTE_MAX_
ATTENUATION
Sets maximum attenuation during soft mute (dB). 0x0008
0x3303
AM_SOFT_MUTE_SNR_
THRESHOLD
Se
ts SNR threshold to engage soft mute. Default is 0 dB, which
disables soft mute.
0x0008
0x3400
AM_SEEK_BAND_
BOTTOM
Sets the bottom of the AM/SW/LW band for seek. Default is 520. 0x0208
