Texas Instruments recommends a layout with a solid ground plane, short traces, and minimal impedance mismatch to ensure high-frequency stability and low noise. A 4-layer PCB with a dedicated analog ground plane is recommended.
The output filter should be chosen based on the specific application requirements. A simple RC filter with a 1kΩ resistor and 10nF capacitor is a good starting point. For more complex filtering, a 2nd-order Butterworth filter or a Bessel filter can be used.
The OPA3690IDBQT can drive up to 1nF of capacitive load. However, it's recommended to limit the capacitive load to 100pF or less to ensure stability and prevent oscillations.
To reduce noise and EMI, use a low-noise power supply, decouple the power pins with 10uF and 100nF capacitors, and use a shielded enclosure. Additionally, keep the analog and digital grounds separate and use a star-grounding configuration.
The OPA3690IDBQT has a thermal derating of 13.9mW/°C above 25°C. This means that the maximum power dissipation decreases by 13.9mW for every degree Celsius above 25°C.
OPA3690IDBQT datasheet
by Texas Instruments
