Getting Started - Analog Devices EVAL-ADA4351-2 User Manual

User Guide

GETTING STARTED

Take the following steps to simply get the EVAL-ADA4351-2EBZ up
and running using a current source as input, as well as to perform
quick functionality tests. Figure 4
in the EVAL-ADA4351-2EBZ. When using a voltage source as an
input is required, refer to the Using Voltage Source as Input
for additional information.
1. Configure and connect the power supplies to be used.
For this quick start, use the following configuration:
►
AVDD (analog positive supply voltage): 2.5 V, 0.1 A
►
AVSS (analog negative supply voltage): −2.5 V, 0.1 A
►
DVDD (digital positive supply voltage): 1.8 V, 0.1 A
►
Connect the supplies to their designated test points (see TPx
►
in Figure 3).
Refer to the Power Supplies
►
to power up the EVAL-ADA4351-2EBZ.
analog and digital supplies operation range.
2. Configure the source meter for the input; set it as current
source.
For this quick start, set the current source to −4 µA to test
►
both a low gain state or a high gain state and −50 µA to test
the low gain state. Refer to
of each setting.
Alternatively, a voltage source in series with a resistor of
►
choice can be used, but the amplifier in turn operates as an
inverting amplifier rather than a TIA.
For this configuration, refer to the
►
as Input section.
3. Connect the current source to the inverting pin of the amplifier
through the SMA inputs.
For Channel A, connect to J1.
►
For Channel B, connect to J4.
►
If the current source has more than 10 pF of capacitance,
►
add a compensation capacitor on C12 or C14. Refer to the
ADA4351-2 data sheet for more details.
4. Select the desired gain for each channel by configuring the
switch control (SW SEL x).
For this quick start, leave the switch control at its default
►
state, which is configured as a quick functionality test (see
Table 4).
By default, SW SEL A for Channel A and SW SEL B for
►
Channel B are set as low.
Install one of the provided jumpers on P5 to set SW SEL A
►
to high.
Install one of the provided jumpers on P4 to set SW SEL B
►
to high.
A low input on SW SEL x activates the SW0 x feedback path,
►
while high input activates the SW1 x feedback path.
analog.com
shows the TIA circuit employed
section
section for the different ways
Table 2 shows the
Table 5 for the expected outputs
Using Voltage Source
EVAL-ADA4351-2
Refer to the Gain Switch Control
►
ways to set the gain states.
feedback path selection and activation.
5. Ground the noninverting input pin of the amplifier using a 0 Ω or
50 Ω SMA termination.
For Channel A, install the termination at J2.
►
For Channel B, install the termination at J3.
►
6. Connect a digital multimeter to the SMA output of the EVAL-
ADA4351-2EBZ.
For Channel A, connect the DMM to J5.
►
For Channel B, connect the DMM to J6.
►
7. Enable the sources as follows:
Turn on the power supply for the analog and digital supplies.
►
Turn on the current source for the input.
►
Toggle the switch control (SW SEL x) to high to satisfy the
►
third test seen in Table 5.
8. Record the measured output as shown in the digital multimeter.
The current input and expected output is shown at
►
When using a voltage source, refer to
►
ed output for the voltage source input test.
Figure 5 shows the full physical setup of one of the ways to get the
EVAL-ADA4351-2EBZ up and running. Follow this quick start guide
to see results like those detailed in
the expected outputs detailed in
For further understanding of the EVAL-ADA4351-2EBZ, see the
EVAL-ADA4351-2EBZ schematic in
Table 5. Expected Outputs
Current Input (µA) SW SEL x
4 Low (no jumper)
50 Low (no jumper)
4 High (jumper installed)
Figure 4. EVAL-ADA4351-2EBZ Test Circuit (I Is the Current Source.)
section for details and other
Table 4 provides details for
Table
Table 7 for the expect-
Table 5; values must ±10% of
Table 5.
Figure 8.
Expected Output (V)
0.1608
2.01
1.996
Rev. 0 | 5 of 9
5.