A 4-layer PCB with a solid ground plane and a separate analog ground plane is recommended. Keep the analog and digital grounds separate and connect them at a single point. Use a star topology for the power supply and keep the signal traces short and direct.
The PGA207UA/1K requires a dual power supply (±5V or ±15V) and a common-mode voltage (VCM) of 0V or 2.5V. Ensure the power supplies are well-regulated and decoupled with 10uF and 100nF capacitors. Use a voltage reference (e.g., TLV7031) to generate the VCM voltage.
The recommended input impedance is 1kΩ to 10kΩ, and the recommended output impedance is 1kΩ to 100kΩ. Impedance matching is critical for optimal performance, so ensure the input and output stages are properly terminated.
Use a shielded enclosure, keep the analog and digital circuits separate, and use differential signaling. Add a common-mode choke or a ferrite bead to the power supply lines to filter out high-frequency noise. Use a low-pass filter or a notch filter to remove specific noise frequencies.
The maximum input signal amplitude is ±10V peak-to-peak (±3.5Vrms) for a gain of 1. For higher gains, the input signal amplitude must be reduced accordingly to avoid clipping and distortion.
PGA207UA/1K datasheet
by Texas Instruments
