There are several critical signals which require specific care during board design:
- Analog input and clock signals
- Traces should be as short as possible and vias should be avoided where possible to minimize impedance discontinuities.
- Traces should be routed using loosely coupled 100Ω differential traces.
- Differential trace lengths are matched as close as possible to minimize phase
imbalance and HD2 degradation.
- Digital output interface
- Traces are routed using tightly coupled 100Ω differential traces.
- Voltage reference
- The bypass capacitor is placed as close to the device pins as possible, and connected between VREF and REFGND on top layer avoiding vias.
- Depending on configuration, an additional bypass capacitor between REFBUF/CTRL
and REFGND is recommended, and is placed as close to pins as possible on
the top layer.
- Power and ground connections
- Provide low resistance connection paths to all power and ground pins.
- Use power and ground planes instead of traces.
- Avoid narrow, isolated paths which increase the connection resistance.
- Use a signal, ground, or power circuit board stack up to maximize coupling between the ground and power plane.