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

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)

Filter Capacitor. HPFL capacitor, sets the high-pass corner frequency.

AGC Filter Capacitor. Capacitor, CAGC, sets closed-loop AGC response time.

R7

Mode Pull-Up Resistor.

R7 = 10 kΩ (Size 0805)

High-Pass Filter Resistor.

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.

57.6

Ω

174

Ω

57.6

Ω

174

Ω

AD8367

Figure 45. Characterization Test Setup