Setup for the DEM-FDA-RUN-EVM includes proper connections to bench equipment, test hardware,
and selection of jumpers. The base process for setup includes:
- Connect power supplies via
the banana jacks, labeled as VCC+, VCC-, and GND.
- Confirm appropriate
quiescent current (IQ) for FDA with no input/output signal
- Determine input and output
connections
- Connect external
input sources through SMA connectors
- Confirm appropriate
input termination and input network resistor values
- Determine amplifier
load network, check impedance of output network for both amplifier
and transformer (or SMA) directions
- For example,
an amplifier may prefer a 1kΩ load, while a transformer or
output SMA connector may need 50Ω termination
- Connect outputs via
SMA connectors, confirm the values of output termination resistors
R11 and R15.
- Use or bypass the
transformer T1.
- Check and confirm load network between FDA outputs and transformer T1.
- Confirm control signals power-down (PD) and output common-mode voltage
control (VOCM)
- Do one of the following:
- Float SMA connections and let the FDA set the control pins
internally
- Force PD voltage using J10 jumper to VCC+ or VCC- as
power-down control
- Drive an external signal into PD and/or VOCM
- PD default is to have FDA turned 'ON' (active-low PD)
- VOCM default is to have FDA VOCM biased to mid-supply
- Begin evaluation of FDA using
DEM-FDA-RUN-EVM