AN332
104
Confidential Rev. 0.2
Table 13. AM/SW/LW Receiver Property Summary
Prop
Name
Description
Default
0x0001
GPO_IEN
Enables interrupt sources.
0x0000
0x0102
DIGITAL_OUTPUT_
FORMAT
Configure digital audio outputs (Si4731/35/37 only)
0x0000
0x0104
DIGITAL_OUTPUT_
SAMPLE_RATE
Configure digital audio output sample rate (Si4731/35/37 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
0x3100
AM_DEEMPHASIS
Sets deemphasis time constant. Can be set to 50 µs. Deemphasis
is disabled by default.
0x0000
0x3102 AM_CHANNEL_FILTER
Selects the bandwidth of the channel filter for AM reception. The
choices are 6, 4, 3, 2, or 1 (kHz) and dynamic. Dynamic mode is
supported by the Si4740/41 only. The default bandwidth is 2 kHz.
0x0003
0x3200 AM_RSQ_INTERRUPTS
Configures interrupt related to Received Signal Quality metrics. All
interrupts are disabled by default.
0x0000
0x3201
AM_RSQ_SNR_HIGH_
THRESHOLD
Sets high threshold for SNR interrupt.
0x007F
0x3202
AM_RSQ_SNR_LOW_
THRESHOLD
Sets low threshold for SNR interrupt.
0x0000
0x3203
AM_RSQ_RSSI_HIGH_
THRESHOLD
Sets high threshold for RSSI interrupt.
0x007F
0x3204
AM_RSQ_RSSI_LOW_
THRESHOLD
Sets low threshold for RSSI interrupt.
0x0000
0x3300 AM_SOFT_MUTE_RATE
Sets the attack and decay rates when entering or leaving soft mute.
The default is 278 dB/s.
0x0040
0x3301
AM_SOFT_MUTE_
SLOPE
Sets the AM soft mute slope. Default value is a slope of 2.
0x0002
0x3302
AM_SOFT_MUTE_MAX_
ATTENUATION
Sets maximum attenuation during soft mute (dB). Set to 0 to dis-
able soft mute. Default is 16 dB.
0x0010
0x3303
AM_SOFT_MUTE_SNR_
THRESHOLD
Sets SNR threshold to engage soft mute. Default is 10 dB.
0x000A
0x3400
AM_SEEK_BAND_
BOTTOM
Sets the bottom of the AM band for seek. Default is 520.
0x0208
0x3401 AM_SEEK_BAND_TOP
Sets the top of the AM band for seek. Default is 1710.
0x06AE
0x3402
AM_SEEK_FREQ_
SPACING
Selects frequency spacing for AM seek. Default is 10 kHz spacing. 0x000A
0x3403
AM_SEEK_SNR_
THRESHOLD
Sets the SNR threshold for a valid AM Seek/Tune. If the value is
zero then SNR threshold is not considered when doing a seek.
Default value is 5 dB.
0x0005
Notes:
1.
DIGITAL_OUTPUT_FORMAT and DIGITAL_OUTPUT_SAMPLE_RATE are supported in AM_SW_LW receive
component 2.0 or higher.
2.
Component 1.0 incorrectly reports 0x06B9 (1721 kHz) as default for AM_SEEK_BAND_TOP. After POWER_UP
command is complete, set AM_SEEK_BAND_TOP to 0x06AE (1710 kHz) using the SET_PROPERTY command.
3.
1 kHz option on AM_CHANNEL_FILTER is supported on AM_SW_LW component 2.A.2 or higher.
Содержание Si4700
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