AD8285 Datasheet, PDF (26/27 Pages) Analog Devices – Radar Receive Path AFE - 4-Channel LNA/PGA/AAF with ADC

AD8285
Data Sheet
The AD8285 can also be driven with a single-ended source, as shown in Figure 34. In this configuration, the negative analog input of each
channel is grounded through a resistor and a 0.1 μF capacitor. For optimal operation, this resistor must match the output impedance of
the input driver.
3.3V
AVDD33REF
0.1µF
3.3V
DVDD33SPI
0.1µF
1.8V
DVDD18
0.1µF
1.8V
AVDD18
0.1µF
AVDD33A
0.1µF
DVDD33CLK
0.1µF
DVDD18CLK
0.1µF
AVDD18
0.1µF
AVDD33B
0.1µF
DVDD33DRV
0.1µF
AVDD18ADC
0.1µF
AVDD33C
0.1µF
DVDD33DRV
0.1µF
AVDD33D
0.1µF
AVDD33
0.1µF
DSYNC
PDWN
NC
1
2
3
4
SCLK
5
10kΩ
SDIO
CS
AUX
MUXA
ZSEL
6
7
8
9
10
11
12
13
14
15
16
R
0.1µF
17
18
NC
DSYNC
PDWN
DVDD18
SCLK
SDIO
CS
AUX
MUXA
ZSEL
TEST1
TEST2
DVDD33SPI
AVDD18
AVDD33A
INA–
INA+
NC
INA
0.1µF
AD8285
TOP VIEW
(Not to Scale)
NC
TEST4
DVDD18CLK
CLK+
CLK–
DVDD33CLK
AVDD33REF
VREF
RBIAS
BAND
APOUT
ANOUT
TEST3
AVDD18ADC
AVDD18
INADC+
INADC–
NC
54
53
52
51
50
49
CLK+
CLK–
48
47
46 _{10kΩ 0.1µF}
45
44 ^1%
43
0.1µF
42
41
40
39
38
37
0.1µF
0.1µF
INADC+
INADC–
INB
0.1µF
0.1µF
IND
INC
0.1µF
NOTES
1. RESISTOR R (INx– INPUTS) MUST MATCH THE OUTPUT IMPEDANCE OF THE INPUT DRIVER.
2. ALL CAPACITORS FOR SUPPLIES AND REFERENCES SHOULD BE PLACED CLOSE TO THE DEVICE.
Figure 34. Single-Ended Inputs Application Diagram
Rev. B | Page 26 of 27