AD8367
Rev. A | Page 20 of 24
Table 7 details the various configuration options of the evaluation board.
Table 7. Evaluation Board Configuration Options
Component Function Default Condition
TP1, TP2 Supply and Ground Vector Pins. Not Applicable
TP3, TP4 Mode and Gain Vector Pins. Not Applicable
SW1
VGA/AGC Select: Used to select VGA (Position A) or AGC (Position B) mode of
operation. SW2 must be set for Position A for AGC mode of operation.
SW1 = A
SW2
MODE Select. Used to select positive or negative VGA slope. Set to Position B for an
increasing gain with V
GAIN
, Position A for decreasing gain law.
SW2 = B
LK1
Device Enable. When LK1 is installed, the ENBL pin is connected to the positive supply
and the AD8367 is in operating mode.
LK1 = Installed
R1, R2
Input Interface. R1 and R2 are used to provide an L-pad impedance-transforming
network. The broadband matching network transforms a 50 Ω source to match a
200 Ω load with 11.5 dB of insertion loss.
R1 = 57.6 Ω (Size 0603)
R2 = 174 Ω (Size 0603)
R3, R4, C4
Output Interface. R3 and R4 are used to transform a 50 Ω load termination to look like
a 200 Ω load with 11.5 dB of insertion loss. The ac coupling capacitor, C4, can be
increased to obtain a lower high-pass corner frequency.
R3 = 57.6 Ω (Size 0603)
R4 = 174 Ω (Size 0603)
C4 = 0.1 μF (Size 0603)
C1, C2, C3, R5, R6
Power Supply Decoupling. The nominal supply decoupling consists of a 1 μF capacitor
to ground, a 4.7 Ω series resistor, and a 0.1 μF capacitor to ground. The same
decoupling network should be used on both the VPSI and VPSO supply lines.
C1 = 1 μF (Size 0603)
R5 = R6 = 4.7 Ω (Size 0805)
C2 = C3 = 0.1 μF (Size 0603)
C5 Internal Supply Decoupling. Capacitor C5 provides midsupply decoupling. C5 = 10 nF (Size 0603)
C
HP
Filter Capacitor. HPFL capacitor, sets the high-pass corner frequency.
C
HP
= 0.01 μF (Size 0805)
R
HP
= 0 Ω (Size 0603)
C
AGC
AGC Filter Capacitor. Capacitor, CAGC, sets closed-loop AGC response time. C
AGC
= 0.1 μF (Size 0805)
R7 Mode Pull-Up Resistor. R7 = 10 kΩ (Size 0805)
R
HP
High-Pass Filter Resistor. R
HP
= 100 Ω (Size)
CHARACTERIZATION SETUP AND METHODS
Minimum-loss, L-pad matching networks were used to
interface standard 50 Ω. A test equipment to the 200 Ω input
impedance during the characterization process. Using a 57.6 Ω
shunt resistor followed by a 174 Ω series resistor provides a
broadband match between the 50 Ω test equipment and the
200 Ω device impedance, as illustrated in
Figure 45. The
insertion loss of this network is 11.5 dB.
02710-045
57.6Ω
174Ω
57.6Ω
174Ω
AD8367
Figure 45. Characterization Test Setup
