ADL5306 Analog Devices, Inc., ADL5306 Datasheet - Page 14

• Manufacturer Part Number: ADL5306
• Description: 60 Db Range 100 Na To 100 Ua Low Cost Logarithmic Converter
• Manufacturer: Analog Devices, Inc.

ADL5306
EVALUATION BOARD
An evaluation board is available for the ADL5306, the schematic
of which is shown in 29. It can be configured for a wide variety
of experiments. The buffer gain is factory-set to unity, providing
Table 4. Evaluation Board Configuration Options
Component
P1
P2, R8, R9, R10, R18
R2, R3, R4, R6, R11, R14, C2, C7, C9, C10
R1, R19
R12, R15, C3, C4, C5, C6
C11
R13, R16, C1, C8
IREF, INPT, PD, LK1, R5
J1
Function
Supply Interface. Provides access to supply pins VNEG,
COMM, and VPOS.
Monitor Interface. By adding 0 Ω resistors to R8, R9, R10,
and R18, the VREF, VSUM, VOUT, and VLOG pin voltages
can be monitored using a high impedance probe.
Buffer Amplifier/Output Interface. The logarithmic slope
of the ADL5306 can be altered using the buffer’s gain-
setting resistors, R2 and R3. R4, R6, R11, R14, C2, C7, C9, and
C10 are provided for a variety of filtering applications.
Intercept Adjustment. The voltage dropped across
resistor R1 determines the intercept reference current,
nominally set to 10 µA using a 200 kΩ 1% resistor.
Supply Decoupling
Filtering VSUM
Input Compensation. Provides essential HF compensation
at the input pins, INPT and IREF.
Input Interface. The test board is configured to accept a
current through the SMA connector labeled INPT. An SC
style packaged photodiode can be used in place of the
INPT SMA for optical interfacing. By removing R1 and
adding a 0 Ω short for R5, a second current can be applied
to the IREF input (also SMA) for evaluating the ADL5306 in
log-ratio applications.
SC Style Photodiode
Rev. 0 | Page 14 of 16
a slope of 200 mV/dec, and the intercept is set to 1 nA. Table 4
describes the various configuration options.
Default Conditions
P1 = Installed
P2 = Not Installed
R8 = R9 = R10 = Open (Size 0603)
R18 = Open (Size 0603)
R2 = R6 = 0 Ω (Size 0603)
R3 = R4 = Open (Size 0603)
R11 = R14 = 0 Ω (Size 0603)
C2 = C7 = Open (Size 0603)
C9 = C10 = Open (Size 0603)
VLOG = VOUT = Installed
R1 = 200 kΩ (Size 0603)
R19 = 0 Ω (Size 0603)
C3 = C4 = 0.01 µF (Size 0603)
C5 = C6 = 0.1 µF (Size 0603)
R12 = R15 = 0 Ω (Size 0603)
C11 = 1 nF (Size 0603)
R13 = R16 = 1 kΩ (Size 0603)
C1 = C8 = 1 nF (Size 0603)
IREF = INPT = Installed
PD = Not Installed
LK1 = Installed
R5 = Open (Size 0603)
J1 = Open