AKD4589 Datasheet, PDF (7/51 Pages) Asahi Kasei Microsystems – AK4589 Evaluation Board Rev.2

ASAHI KASEI
[AKD4589-B]
„ B, U, C, V output and V input
B, U, C, V output and V input is used PORT4 (BUCV).
PORT4 pin order is showed Figure 6.
„ Analog Inputs
PORT4
10 ^BUCV
GND
9
BOUT
GND
COUT
GND
UOUT
GND
VOUT
GND
VIN
2
1
Figure 6. PORT4 pin order
BNC connector J10 (LIN),J9 (RIN) are used for analog inputs on the AKD4589-B. Analog inputs are single-ended
and input ranges of each channels are nominally 6.2Vpp@5V. (Input ranges of each channels of analog inputs of
AK4589 device are nominally [e-mail],for the resister division,the value which analog input level of
Evaluation Board is devided by two becomes to analog input level of AK4589 device on the AKD4589-B. So, input
ranges of AKD4589-B becomes to 6.2Vpp@5V,twice of the value in the case of AK4589 device. Input range of
AK4589 device is proportional to VREFH (3.1=0.62 x VREFH). VREFH is connected to AVDD on the
AKD4589-B.)
„ Analog Input Circuit
3.1Vpp
AK4589
RIN 33
LIN 32
22u
330
Op-amp circuit
330 ^NJM4580
+
-
6.2Vpp
Signal
Same circuit
Figure 7. Analog Input Circuit
1) Gain
Gain of analog input circuit is
330/(330+330) = -6.02dB.
Therefore input level for this board is
+0.80dBV(=3.1Vpp)+6.02dB
= +6.82dBV = 6.20Vpp = 2.19Vrms.
2) S/N of op-amp circuit (Theory: BW=20k+A)
Non-inverting amp is implemented on board. The output noise level of op-amp circuit is
-126.01dBV = -132.54dB (0dB=+6.53dBV).
S/N of ADC is
101.6dB (measurement).
Therefore total S/N of op-amp circuit and ADC is
101.60dB (measurement: 101.6dB)
<KM076201>
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2005/07