PCB Board Layout Restoration

In the process of PCB Board Layout Restoration, there are a number of important points to be considered when making signal and power connections. First of all a connector is one of the few places in the system where all signal conductors must run in parallel—it is therefore imperative to separate them with ground pins (creating a Faraday shield) to reduce coupling between them.

Multiple ground pins are important for another reason: they keep down the ground impedance at the junction between the board and the backplane. The contact resistance of a single pin of a PCB connector is quite low (typically on the order of 10 m) when the board is new—as the board gets older the contact resistance is likely to rise, and the board’s performance may be compromised. It is therefore well worthwhile to allocate extra PCB connector pins so that there are many ground connections (perhaps 30% to 40% of all the pins on the PCB connector should be ground pins). For similar reasons there should be several pins for each power connection.

Manufacturers of high performance mixed-signal ICs, like Analog Devices, often offer evaluation boards to assist customers in their initial evaluations and PCB Board Layout Restoration. ADC evaluation boards generally contain an on-board low jitter sampling clock oscillator, output registers, and appropriate power and signal connectors. They also may have additional support circuitry such as the ADC input buffer amplifier and external reference when PCB Board Layout Restoration.