SI4736-B20 Datasheet, PDF (26/38 Pages) Silicon Laboratories – BROADCAST WEATHER BAND RADIO RECEIVER

Si4736/37/38/39-B20
Table 15. Si473x Property Summary
Prop
Name
Description
Default
0x0001
GPO_IEN
Enables interrupt sources.
0x0000
0x0102 DIGITAL_OUTPUT_FORMAT Configures the digital output format (Si4737/39 only).
0x0000
0x0104
DIGITAL_OUTPUT_
SAMPLE_RATE
Configures the digital output sample rate in 100 Hz steps. The
digital output sample rate is disabled by default (Si4737/39
only).
0x0000
0x0201
REFCLK_FREQ
Sets frequency of reference clock in Hz. The range is 31130 to
34406 Hz, or 0 to disable the AFC. Default is 32768 Hz.
0x8000
0x0202 REFCLK_PRESCALE Sets the prescaler value for RCLK input.
0x0001
0x1100
FM_DEEMPHASIS
Sets de-emphasis time constant. Default is 75 us.
0x0002
0x1105
FM_BLEND_STEREO_
THRESHOLD
Sets RSSI threshold for stereo blend (Full stereo above thresh-
old, blend below threshold). To force stereo set this to 0. To
0x0031
force mono set this to 127. Default value is 49 dBuV.
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 0x001E
mono set this to 127. Default value is 30 dBuV.
0x1108
FM_MAX_TUNE_
ERROR
Sets the maximum freq error allowed before setting the AFC rail
(AFCRL) indicator. Default value is 30 kHz.
0x001E
0x1200
FM_RSQ_INT_
SOURCE
Configures interrupt related to RSQ metrics.
0x0000
0x1201
FM_RSQ_SNR_HI_
THRESHOLD
Sets high threshold for SNR interrupt.
0x007F
0x1202
FM_RSQ_SNR_LO_
THRESHOLD
Sets low threshold for SNR interrupt.
0x0000
0x1203
FM_RSQ_RSSI_HI_
THRESHOLD
Sets high threshold for RSSI interrupt.
0x007F
0x1204
FM_RSQ_RSSI_LO_
THRESHOLD
Sets low threshold for RSSI interrupt.
0x0000
0x1207
FM_RSQ_BLEND_
THRESHOLD
Sets the blend threshold for blend interrupt when boundary is
crossed.
0x0081
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 dis-
able 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
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Rev. 1.0