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AN332
Confidential Rev. 0.2
53
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 deemphasis time constant. Default is 75 µs. (Not applicable
for Si4749.)
0x0002
0x1102
FM_CHANNEL_FILTER
Sets state of the channel filter for demodulator (Si4706/49 only).
0x0000
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. (Not applicable for
Si4740/41/49.)
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. (Not applicable for
Si4740/41/49.)
0x001E
0x1107
FM_ANTENNA_INPUT
Selects the antenna type and the pin to which it is connected.
(Si4704/05/06/20/21 only).
0x0000
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 Received Signal Quality 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
0x1205
FM_RSQ_MULTIPATH_HI_
THRESHOLD
Sets high threshold for multipath interrupt (Si4706/40/41/49 only)
0x007F
0x1206
FM_RSQ_MULTIPATH_
LO_THRESHOLD
Sets low threshold for multipath interrupt (Si4706/40/41/49 only)
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. (Not applicable for Si4749.)
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. (Not applicable for Si4749.)
0x0010
0x1303
FM_SOFT_MUTE_
SNR_THRESHOLD
Sets SNR threshold to engage soft mute. Default is 4 dB.
(Not applicable for Si4749.)
0x0004
Table 9. FM/RDS Receiver Property Summary (Continued)
Prop
Name
Description
Default
Notes:
1.
Digital Audio Output feature (property DIGITAL_OUTPUT_FORMAT and DIGITAL_OUTPUT_SAMPLE_RATE) is
supported in FMRX component 2.0 or higher. Digital Audio Output featured is not supported on Si4741 FMRX component
2A.7.
2.
RDS feature (command FM_RDS_STATUS and property RDS_INT_SOURCE, RDS_INT_FIFO_COUNT, and
RDS_CONFIG) is supported in FMRX component 2.0 or higher.