LP39542 Datasheet, PDF (53/58 Pages) National Semiconductor (TI) – Advanced Lighting Management Unit

AUDIO_SYNC_CTRL1 (2AH) – AUDIO SYNCHRONIZATION AND ADC CONTROL REGISTER 1
D7
D6
D5
gain_sel[2:0]
rw-0
rw-0
rw-0
D4
sync_mode
rw-0
D3
en_agc
rw-0
D2
en_sync
rw-0
D1
D0
input_sel[1:0]
rw-1
rw-1
gain_sel[2:0]
sync_mode
en_agc
en_sync
input_sel[1:0]
Bits 7-5
Bit 4
Bit 3
Bit 2
Bits 1-0
Input signal gain control
gain_sel[2:0]
gain, dB
000
0 (default)
001
3
010
6
011
9
100
12
101
15
110
18
111
21
Input filter mode control
0 – Amplitude mode
1 – Frequency mode
0 – automatic gain control disabled
1 – automatic gain control enabled
0 – audio synchronization disabled
1 – audio synchronization enabled
ADC input selector
input_sel[1:0]
Input
00
Single ended input signal (ASE)
01
Temperature measurement
10
Ambient light measurement
11
No input (default)
AUDIO_SYNC_CTRL2 (2BH) – AUDIO SYNCHRONIZATION AND ADC CONTROL REGISTER 2
D7
D6
D5
D4
D3
D2
D1
D0
en_avg
mode_ctrl[1:0]
speed_ctrl[1:0]
r-0
r-0
r-0
rw-0
rw-0
rw-0
rw-0
rw-0
en_avg
mode_ctrl[1:0]
speed_ctrl[1:0]
Bit 4
Bits 3-2
Bits 1-0
0 – averaging disabled. f_sample = 122 Hz, data in
register changes every 8.2 ms.
1 – averaging enabled. f_sample = 244 Hz, averaging of
64 samples, data in register changes every 262 ms
(3.2Hz).
Filtering mode control
LEDs light response time to audio input
speed_ctrl[1:0]
Response
00
FASTEST (default)
01
FAST
10
MEDIUM
11
SLOW
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