Achieving optimum performance with a high-frequency amplifier (like the OPAx863) requires careful attention to board layout parasitics and external component types. The OPA2863 DGK Evaluation Module user's guide can be used as a reference when designing the circuit board. Recommendations that optimize performance includes the following:

1. Minimize parasitic capacitance to any ac ground for all of the signal I/O pins. Parasitic capacitance on the output and inverting input pins can cause instability on the noninverting input and can react with the source impedance to cause unintentional band-limiting. Open a window around the signal I/O pins in all of the ground and power planes around those pins to reduce unwanted capacitance. Otherwise, ground and power planes must be unbroken elsewhere on the board.
2. Minimize the distance (< 0.1 in) from the power-supply pins to high-frequency 0.01-µF decoupling capacitors. Avoid narrow power and ground traces to minimize inductance between the pins and the decoupling capacitors. The power-supply connections must always be decoupled with these capacitors. Larger (2.2-µF to 6.8-µF) decoupling capacitors, effective at lower frequency, must also be used on the supply pins. These capacitors can be placed somewhat farther from the device and shared among several devices in the same area of the PCB.
3. Careful selection and placement of external components preserves the high-frequency performance of the OPAx863. Resistors must be a low reactance type. Surface-mount resistors work best and allow a tighter overall layout. Other network components, such as noninverting input termination resistors, must also be placed close to the package. Keep resistor values as low as possible and consistent with load-driving considerations. Lowering the resistor values keeps the resistor noise terms low and minimizes the effect of the parasitic capacitance. Lower resistor values, however, increase the dynamic power consumption because R_F and R_G become part of the amplifier output load network.