AKM AKD4385-SC User manual

ASAHI KASEI [AKD4385-SC]
<KM082701> 1 2006/04
General Description
The AKD4385-SC is an evaluation board for AK4385, which is 192kHz sampling 24Bit ∆Σ DAC. The
AKD4385-SC includes a LPF which can add differential analog outputs from the AK4385 and also has a digital
interface. Therefore, it is easy to evaluate the AK4385.
Ordering Guide
AKD4385-SC --- Evaluation board for AK4385
Function
On-board Analog output buffer circuit
On-board digital audio interface. (AK4113)
AK4385
AK4113
COAX In
Rch
Lch
DIR
Opt In
2nd Order
LPF
AGND -15V
+3.3V Reg
+15V
Reg +5V
PORT1
EXT
PORT2
Control
Data
Figure 1. Block diagram
* Circuit diagram and PCB layout are attached at the end of this manual.
COAX is recommended for an evaluation of the Sound quality.
A
K4385 Evaluation board Rev.1
A
KD4385-SC

ASAHI KASEI [AKD4385-SC]
<KM082701> 2 2006/04
Operation sequence
1) Set up the power supply lines. (See “Other jumpers set-up”.)
Name Color Voltage Comments Attention
+15V Red
+12∼+15V For regulator and op-amps. This jack should be always connected to power
supply.
-15V Blue
-12∼-15V For op-amps. This jack should be always connected to power
supply.
AGND Black 0V GND This jack should be always connected to power
supply.
Table 1. Set up of power supply lines
Each supply line should be distributed from the power supply unit.
2) Set-up the jumper pins
3) Set-up the DIP switches. (See the followings.)
4) Power on
The AK4385 should be reset once by bringing SW1 (PDN) “L” upon power-up.

ASAHI KASEI [AKD4385-SC]
<KM082701> 3 2006/04
Evaluation mode
1. DIR (COAX) (default)
It is possible to evaluate the AK4385 by using CD disk. The DIR generates MCLK, BICK, LRCK and SDATA from the
received data through BNC connector (J1). Setting of jumper is shown below.
COAX is recommended for an evaluation of the Sound quality.
JP4
OPT
COAX
RX
(Default)
Figure 2. Jumper setting, when using DIR
2. DIR (Optical Link)
It is possible to evaluate the AK4385 by using CD disk. The DIR generates MCLK, BICK, LRCK and SDATA from the received
data through optical connector (PORT3: TORX176). Setting of jumper is shown below.
JP4
OPT
COAX
RX
Figure 3. Jumper setting, when using DIR
3. All clocks are fed through the PORT1.
R13, R15, R17, R18 : open
R1, R2, R3, R8 : 100Ωor short (0Ω)
DIP Switch setting
[SW2]: AK4113 setting
No. Pin OFF ON Default
1 OCKS1 ON
2 OCKS0
AK4113 Master Clock setting
Refer to Table4 OFF
Table 2. SW2 setting
The frequency of the master clock output is set by OCKS0 and OCKS1 as shown in Table 4.
OCKS1 OCKS0 MCLK Frequency
0 0 256fs @fs=88.2/96kHz
1 0 512fs @32/44.1/48kHz
1 1 128fs @176.4/192kHz
Default
Table 3. MCLK Clock

ASAHI KASEI [AKD4385-SC]
<KM082701> 4 2006/04
SW1 setting
[SW1](PDN): Reset of AK4385. Select “H” during operation.
External Analog Filter Circuit
The 2nd order LPF (fc=93.2kHz, Q=0.712) which adds differential outputs of the AK4385 is implemented on the board. When
the further attenuation of the out-of-band noise is needed, some additional LPF is required. Analog signal is output through
BNC connectors on the board. And the output level of the AK4382A is 5.5Vpp@5V.
LOUT-
(ROUT-)
-
LOUT+
(ROUT+)
+15V
-15V
NJM4580D
R1
C1
R3
R2
C2
R1R3
R2C2
22u
10k
+
100
Figure 4. On-board analog filter
R1R
2R 3C 1C 2
4.7k 4.7k 200 3300p 470p
Table 4. The value of R, C on this board
fin 20kHz 40kHz 80kHz
Frequency Response -0.003dB -0.122dB -1.821dB
Table 5. Frequency Response of LPF
<Calculation>
fc= ω0
2π,
ω0= 1
2C1C2R2R3
,
Q= 2C1
ω
0.
+
1
R1+
1
R2
1
R3
Amplitude = 20 log [1-(f/fc)2]2+[(1/Q)(f/fc)] 2
K [dB],
K= R2
R1,

ASAHI KASEI [AKD4385-SC]
<KM082701> 5 2006/04
Control Software Manual
Set-up of evaluation board and control software
1. Set up the AKD4385-SC according to previous term.
2. Connect IBM-AT compatible PC with AKD4385-SC by 10-line type flat cable (packed with AKD4385-SC). Take
care of the direction of 10pin header. (Please install the driver in the CD-ROM when this control software is used
on Windows 2000/XP. Please refer “Installation Manual of Control Software Driver by AKM device control
software”. In case of Windows95/98/ME, this installation is not needed. This control software does not operate on
Windows NT.)
3. Insert the CD-ROM labeled “AKD4385-SC Evaluation Kit” into the CD-ROM drive.
4. Access the CD-ROM drive and double-click the icon of “AKD4385-SC.exe” to set up the control program.
5. Then please evaluate according to the follows.
Operation flow
Keep the following flow.
1. Set up the control program according to explanation above.
2. Click “Port Reset” button.
Explanation of each buttons
1. [Port Reset] : Set up the USB interface board (AKDUSBIF-A) in case using the board.
2. [Write default] : Initialize the register of AK4385.
3. [All Write] : Write all registers that is currently displayed.
4. [Function1] : Dialog to write data by keyboard operation.
5. [Function2] : Dialog to write data by keyboard operation.
6. [Function3] : The sequence of register setting can be set and executed.
7. [Function4] : The sequence that is created on [Function3] can be assigned to buttons and
executed.
8. [Function5]: The register setting that is created by [SAVE] function on main window can
be assigned to buttons and executed.
9. [SAVE] : Save the current register setting.
10. [OPEN] : Write the saved values to all register.
11. [Write] : Dialog to write data by mouse operation.
Indication of data
Input data is indicated on the register map. Red letter indicates “H” or “1” and blue one indicates “L” or “0”. Blank is
the part that is not defined in the datasheet.

ASAHI KASEI [AKD4385-SC]
<KM082701> 6 2006/04
Explanation of each dialog
1. [Write Dialog] : Dialog to write data by mouse operation
There are dialogs corresponding to each register.
Click the [Write] button corresponding to each register to set up the dialog. If you check the check box, data
becomes “H” or “1”. If not, “L” or “0”.
When writing the input data to AK4385, click [OK] button. If not, click [Cancel] button.
2. [Function1 Dialog] : Dialog to write data by keyboard operation
Address Box: Input registers address in 2 figures of hexadecimal.
Data Box: Input registers data in 2 figures of hexadecimal.
When writing the input data to AK4385, click [OK] button. If not, click [Cancel] button.
3. [Function2 Dialog] : Dialog to evaluate ATT
Address Box: Input registers address in 2 figures of hexadecimal.
Start Data Box: Input starts data in 2 figures of hexadecimal.
End Data Box: Input end data in 2 figures of hexadecimal.
Interval Box: Data is written to AK4642 by this interval.
Step Box: Data changes by this step.
Mode Select Box:
With checking this check box, data reaches end data, and returns to start data.
[Example] Start Data = 00, End Data = 09
Data flow: 00 01 02 03 04 05 06 07 08 09 09 08 07 06 05 04 03 02 01 00
Without checking this check box, data reaches end data, but does not return to start data.
[Example] Start Data = 00, End Data = 09
Data flow: 00 01 02 03 04 05 06 07 08 09
When writing the input data to AK4385, click [OK] button. If not, click [Cancel] button.

ASAHI KASEI [AKD4385-SC]
<KM082701> 7 2006/04
4. [Save] and [Open]
4-1. [Save]
Save the current register setting data. The extension of file name is “akr”.
(Operation flow)
(1) Click [Save] Button.
(2) Set the file name and push [Save] Button. The extension of file name is “akr”.
4-2. [Open]
The register setting data saved by [Save] is written to AK4385. The file type is the same as [Save].
(Operation flow)
(1) Click [Open] Button.
(2) Select the file (*.akr) and Click [Open] Button.

ASAHI KASEI [AKD4385-SC]
<KM082701> 8 2006/04
5. [Function3 Dialog]
The sequence of register setting can be set and executed.
(1) Click [F3] Button.
(2) Set the control sequence.
Set the address, Data and Interval time. Set “-1” to the address of the step where the sequence should be paused.
(3) Click [Start] button. Then this sequence is executed.
The sequence is paused at the step of Interval="-1". Click [START] button, the sequence restarts from the paused step.
This sequence can be saved and opened by [Save] and [Open] button on the Function3 window. The extension of file
name is “aks”.
Figure 4. Window of [F3]

ASAHI KASEI [AKD4385-SC]
<KM082701> 9 2006/04
6. [Function4 Dialog]
The sequence that is created on [Function3] can be assigned to buttons and executed. When [F4] button is clicked, the
window as shown in Figure 5 opens.
Figure 5. [F4] window

ASAHI KASEI [AKD4385-SC]
<KM082701> 10 2006/04
6-1. [OPEN] buttons on left side and [START] buttons
(1) Click [OPEN] button and select the sequence file (*.aks).
The sequence file name is displayed as shown in Figure 6.
Figure 6. [F4] window(2)
(2) Click [START] button, then the sequence is executed.
6-2. [SAVE] and [OPEN] buttons on right side
[SAVE] : The sequence file names can assign be saved. The file name is *.ak4.
[OPEN] : The sequence file names assign that are saved in *.ak4 are loaded.
6-3. Note
(1) This function doesn't support the pause function of sequence function.
(2) All files need to be in same folder used by [SAVE] and [OPEN] function on right side.
(3) When the sequence is changed in [Function3], the file should be loaded again in order to reflect the change.

ASAHI KASEI [AKD4385-SC]
<KM082701> 11 2006/04
7. [Function5 Dialog]
The register setting that is created by [SAVE] function on main window can be assigned to buttons and executed. When
[F5] button is clicked, the following window as shown in Figure 7opens.
Figure 7. [F5] window
7-1. [OPEN] buttons on left side and [WRITE] button
(1) Click [OPEN] button and select the register setting file (*.akr).
(2) Click [WRITE] button, then the register setting is executed.
7-2. [SAVE] and [OPEN] buttons on right side
[SAVE] : The register setting file names assign can be saved. The file name is *.ak5.
[OPEN] : The register setting file names assign that are saved in *.ak5 are loaded.
7-3. Note
(1) All files need to be in same folder used by [SAVE] and [OPEN] function on right side.
(2) When the register setting is changed by [Save] Button in main window, the file should be loaded again in order to reflect
the change.

ASAHI KASEI [AKD4385-SC]
<KM082701> 12 2006/04
Measurement Results
[Measurement condition]
•Measurement unit : Audio Precision System two Cascade (AP2)
•MCLK : 512fs (44.1kHz), 256fs (96kHz), 128fs (192kHz)
•BICK : 64fs
•fs : 44.1kHz, 96kHz
•Bit : 24bit
•Power Supply : VDD=5V
•Interface : Internal DIR (44.1kHz, 96kHz)
•Temperature : Room
fs=44.1kHz
Parameter Input signal Measurement filter Lch Rch
S/(N+D) 1kHz, 0dB 20kLPF 95.4 dB 95.3 dB
DR 1kHz, -60dB 22kLPF, A-weighted 108.7 dB 108.7 dB
S/N “0” data 22kLPF, A-weighted 109.3 dB 109.3 dB
fs=96kHz
Parameter Input signal Measurement filter Lch Rch
S/(N+D) 1kHz, 0dB 40kLPF 91.3 dB 91.5 dB
40kLPF 104.4 dB 104.4 dB
DR 1kHz, -60dB
22kLPF, A-weighted 107.8 dB 107.8 dB
40kLPF 105.7 dB 105.6 dB
S/N “0” data
22kLPF, A-weighted 108.9 dB 108.8 dB
fs=192kHz
Parameter Input signal Measurement filter Lch Rch
S/(N+D) 1kHz, 0dB 40kLPF 92.7 dB 93.2 dB
40kLPF 103.4 dB 103.4 dB
DR 1kHz, -60dB
22kLPF, A-weighted 106.3 dB 106.3 dB
40kLPF 104.6 dB 104.6 dB
S/N “0” data
22kLPF, A-weighted 108.0 dB 107.0 dB

ASAHI KASEI [AKD4385-SC]
<KM082701> 13 2006/04
Plots
(fs=44.1kHz)
AKM AK4385 FFT
VDD=5V, fs=44.1kHz, MCLK=512, 0dBFS input, fin=1kHz
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k50 100 200 500 1k 2k 5k 10k
Hz
Figure 8. FFT (fin=1kHz, 0dBFS input)
AKM AK4385 FFT
VDD=5V, fs=44.1kHz, MCLK=512, -60dBFS input, fin=1kHz
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k50 100 200 500 1k 2k 5k 10k
Hz
Figure 9. FFT (fin=1kHz, -60dBFS input)

ASAHI KASEI [AKD4385-SC]
<KM082701> 14 2006/04
(fs=44.1kHz)
AKM AK4385 FFT
VDD=5V, fs=44.1kHz, MCLK=512, fin=No signal
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k50 100 200 500 1k 2k 5k 10k
Hz
Figure 10. FFT (Noise Floor)
AKM AK4385 FFT Out-of-band noise
VDD=5V, fs=44.1kHz, MCLK=512fs, fin=No signal
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 100k50 100 200 500 1k 2k 5k 10k 20k 50k
Hz
Figure 11. FFT (Out of band noise)

ASAHI KASEI [AKD4385-SC]
<KM082701> 15 2006/04
(fs=44.1kHz)
AKM AK4385 THD+N vs. Input Level
VDD=5V,fs=44.1kHz, MCLK=512fs, fin=1kHz
-120
-70
-115
-110
-105
-100
-95
-90
-85
-80
-75
d
B
r
A
-120 +0-110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10
dBFS
Figure 12 . THD+N vs. Input level (fin=1kHz)
AKM AK4385 THD+N vs. Input Frequency
VDD=5V, fs=44.1kHz, MCLK=512fs, 0dBFS input
-120
-70
-115
-110
-105
-100
-95
-90
-85
-80
-75
d
B
r
A
20 20k50 100 200 500 1k 2k 5k 10k
Hz
Figure 13 . THD+N vs. Input Frequency (0dBFS input)

ASAHI KASEI [AKD4385-SC]
<KM082701> 16 2006/04
(fs=44.1kHz)
AKM AK4385 Linearity
VDD=5V fs=44.1kHz, MCLK=512fs, fin=1kHz
-120
+0
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
-120 +0-110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10
dBFS
Figure 14. Linearity (fin=1kHz)
AKM AK4385 Frequency Response
VDD=5V, fs=44.1kkHz, MCLK=512fs, 0dBFS input
-1
+1
-0.9
-0.8
-0.7
-0.6
-0.5
-0.4
-0.3
-0.2
-0.1
+0
+0.1
+0.2
+0.3
+0.4
+0.5
+0.6
+0.7
+0.8
+0.9
d
B
r
A
2k 20k4k 6k 8k 10k 12k 14k 16k 18k
Hz
Figure 15. Frequency Response (0dBFS input)

ASAHI KASEI [AKD4385-SC]
<KM082701> 17 2006/04
(fs=44.1kHz)
AKM AK4385 Crosstalk (Red=Lch, Blue=Rch)
VDD=5V, fs=44.1kHz, MCLK=512fs, 0dBFS input
-140
-80
-135
-130
-125
-120
-115
-110
-105
-100
-95
-90
-85
d
B
20 20k50 100 200 500 1k 2k 5k 10k
Hz
Figure 16. Crosstalk (0dBFS input)

ASAHI KASEI [AKD4385-SC]
<KM082701> 18 2006/04
(fs=96kHz)
AKM AK4385 FFT
VDD=5V, fs=96kHz, MCLK=256fs, 0dBFS input, fin=1kHz
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
40 40k50 100 200 500 1k 2k 5k 10k 20k
Hz
Figure 17. FFT (fin=1kHz, 0dBFS input)
AKM AK4385 FFT
fs=96kHz, MCLK=256fs, fin=1kHz, 0dBFS input, Notch=ON
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
40 40k50 100 200 500 1k 2k 5k 10k 20k
Hz
Figure 18. FFT(fin=1kHz, 0dBFS input, Notch)

ASAHI KASEI [AKD4385-SC]
<KM082701> 19 2006/04
(fs=96kHz)
AKM AK4385 FFT
VDD=5V, fs=96kHz, MCLK=256fs, -60dBFS input, fin=1kHz
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
40 40k50 100 200 500 1k 2k 5k 10k 20k
Hz
Figure 19. FFT (fin=1kHz, -60dBFS input)
AKM AK4385 FFT
VDD=5V, fs=96kHz, fin=No signal
-180
+0
-170
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
40 40k50 100 200 500 1k 2k 5k 10k 20k
Hz
Figure 20. FFT (Noise Floor)

ASAHI KASEI [AKD4385-SC]
<KM082701> 20 2006/04
(fs=96kHz)
AKM AK4385 THD+Nvs. Input Level
VDD=5V, fs=96kHz, MCLK=256fs, fin=1kHz
-120
-70
-115
-110
-105
-100
-95
-90
-85
-80
-75
d
B
r
A
-120 +0-110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10
dBFS
Figure 21. THD+N vs. Input level (fin=1kHz)
AKM AK4385 THD+N vs. Input Frequency
VDD=5V, fs=96kHz, MCLK=256fs, 0dBFS input
-120
-70
-115
-110
-105
-100
-95
-90
-85
-80
-75
d
B
r
A
40 40k50 100 200 500 1k 2k 5k 10k 20k
Hz
Figure 22. THD+N vs. Input Frequency (0dBFS input)