Backplane testers evaluate and record the integrity of backplanes and passive electronic components such as resistors, capacitors, and diodes. Backplanes are printed circuit boards (PCBs) that contain slots or sockets for expansion boards and other electronic devices. They distribute low-voltage power to each slot and enable high-speed communications. Typically, backplanes contain multiple card cages and are used in large-scale network switching and routing applications. Some backplane testers are continuity analyzers that measure opens and shorts over a large amount of test points. These devices are suitable for traditional PCBs, but do not provide the ability to clamp the compliance voltage or current. Other backplane testers use techniques commonly associated with the in-circuit testing of loaded boards. Manufacturing defect analyzers (MDAs), an alternative to in-circuit testers, are well-suited for the analog testing of backplanes with high pin counts.