AD8306-EVAL Analog Devices Inc, AD8306-EVAL Datasheet - Page 2

• Manufacturer Part Number: AD8306-EVAL
• Manufacturer: Analog Devices Inc

Specifications of AD8306-EVAL

• Lead Free Status / Rohs Status: Not Compliant

EVAL-AD8306EB
Component
SW1
R1
R/L, C1, C2
R3/R4
L1, C5, C6
R8, LK1
C7
Function
Device Enable. When in Position A, the ENBL pin is connected to +V
AD8306 is in normal operating mode. In Position B, the ENBL pin is connected
to an SMA connector labeled Ext Enable. A signal can be applied to this connector
to enable/disable the AD8306.
This pad is used to ac-couple INLO to ground for single-ended input drive. To drive
the AD8306 differentially, R1 should be removed.
Input Interface. The 52.3 W resistor in position R10, along with C1 and C2, create
a high-pass input filter whose corner frequency (640 kHz) is equal to 1/(2pRC),
where C = (C1)/2 and R is the parallel combination of 52.3 W and the AD8306’s
input impedance of 1000 W. Alternatively, the 52.3 W resistor can be replaced by
an inductor to form an input matching network. See the Input Matching Network
section in the AD8306 data sheet for more details.
Slope Adjust. A simple slope adjustment can be implemented by adding a resistive
divider at the VLOG output. R3 and R4, whose sum should be about 1 kW and
never less than 40 W (see specs), set the slope according to the equation:
Slope = 20 mV/dB ¥ R4/(R3 + R4).
Limiter Output Coupling. C5 and C6 ac-couple the limiter’s differential outputs.
By adjusting these values and installing an inductor in L1, an output matching
network can be implemented. To convert the limiter’s differential output to single-
ended, R11 and R12 (nominally 0 W) can be replaced with a surface mount balun
such as the ETC1-1-13 (Macom). The balun can be grounded by soldering a 0 W
into Position R9 (nominally open).
Limiter Output Current. With LK1 installed, R8 enables and sets the limiter
output current. The limiter’s output current is set according to the equation
(I
To disable the limiter (recommended if the limiter is not being used), LK1 should
be removed.
RSSI Bandwidth Adjust. The addition of C7 (farads) will lower the RSSI bandwidth of
the VLOG output according to the equation: f
OUT
= 400 mV/R8). The limiter current can be as high as 10 mA (R8 = 40 W).
Table I. Evaluation Board Setup Options
CORNER
–2–
(Hz) = 12.7 ¥ 10
–6
/(C7 + 3.5 ¥ 10
S
and the
–12
).
LK1 Installed. R8 = 402 W
Default Condition
SW1 = A
R1 = 0 W
R10 = 52.3 W
C1 = C2 = 0.01 mF
R3 = 0 W
R4 =
L1 = Open
C5 = 0.01 mF
C6 = 0.01 mF
R9 = Open
R10 = R11 = 0 W
R6, R7 (Limited Load
Resistors) = 50 W
C7 = Open
REV. 0