AD831
Single Supply Operation
Figure 26 is similar to the dual supply circuit in Figure 19. Sup-
plies may be as low as 9 V but should not be higher than
11 V due to power dissipation. As in Figure 19, both the RF
and LO ports are driven single-ended and terminated.
+9V
0.1µF
82pF
In single supply operation, the COM terminal is the “ground”
reference for the output amplifier and must be biased to 1/2 the
supply voltage, which is done by resistors R1 and R2. The OUT
pin must be ac-coupled to the load.
82pF
+5V
3
2
1
20
19
AN
50Ω
4
IFN
VP
IFP
50Ω
AP
COM
18
5kΩ
5kΩ
R2
51.1Ω
0.1µF
R1
110Ω
R
T
C
C
GND
5
VN
RFP
VFB
17
C1
RF
INPUT
L1
C2
6
OUT
16
IF
OUTPUT
0.1µF
7
RFN
AD831
Top View
VN
15
8
VN
BIAS
14
NC
VP
9
LON
10
LOP
11
VP
12
GND
13
0.1µF
+9V
0.1µF
51.1Ω
0.1µF
0.1µF
+9V
LO INPUT
–10 dBm
Figure 26. Connections for +9 V Single-Supply Operation
REV. B
–11–
AD [ ANALOG DEVICES ]
