Manual
AN234
3
3. Pin Compatibility
Table 1 shows the pins of the AK5394A and the corresponding pins of the CS5381. Please note that the
AK5394A has 28 pins, and the CS5381 has 24 pins.
Table 2. Pin Compatibility Between AK5394A and CS5381
4. Offset Calibration
The CS5381, and AK5394A all have offset calibration capability. However, the calibration process varies
slightly between the AK5394A and the CS5381.
4.1 CS5381
The CS5381 implements a high pass filter that can be controlled via the HPF
pin (pin 11). The high pass
filter continuously subtracts a measure of the DC offset from the output of the decimation filter. If the HPF
pin is taken high during normal operation, the current value of the DC offset register is frozen and this DC
offset will continue to be subtracted from the conversion result.
A system calibration can then be performed by first running the CS5381 with the high pass filter enabled
(HPF = LOW) until the filter settles. At this point, disable the high pass filter (HPF = HI), thereby freezing
the stored DC offset.
AK5394A CS5381 Description
Pin Number Pin Name Pin Number
Pin Name
1, 28 VREFL+, VREFR+ 24
FILT+
Positive reference voltage
2, 27 VREFL-, VREFR- 23
REFGND
Ground reference
3, 26 VCOML, VCOMR 22
VQ
Internal quiescent reference voltage
4 AINL+ 16
AINL+
Differential Left Channel Input
5 AINL- 17
AINL-
Differential Left Channel Input
6ZCAL -
-
Zero Calibration Control
7VD 6
VD
Digital power
8DGND 7
GND
Ground reference
9CAL -
-
Calibration Active Signal
10 RST 1
RST
Reset
11 SMODE2 12
I2S/LJ
Digital Interface Format Select
12 SMODE1 2
M/S
Master/Slave Mode Select
13 LRCK 3
LRCK
Left right clock
14 SCLK 4
SCLK
Serial clock
15 SDATA 9
SDOUT
Serial data
16 FSYNC -
-
Frame Synchronization Signal
17 MCLK 5
MCLK
Master clock
18 DFS0 13
M0
Mode selection
19 HPFE 11
HPF
High Pass Filter Enable
20 DFS1 14
M1
Mode selection
21 BGND -
-
Substrate Ground
22 AGND 18
GND
Ground reference
23 VA 19
VA
Analog power
24 AINR- 20
AINR-
Differential Right Channel Input
25 AINR+ 21
AINR+
Differential Right Channel Input
8
VL
Logic Power
10
MDIV
MCLK divider
15
OVFL
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