Don't tie IC control lines directly to power or ground. Add pull-up or pull-down resistors.This permits the ICT to control these lines when required during IC testing. 1.Place test points away from BGA components to reduce BGA solder stress and board flex.2.Have a test point for all electrical nodes, including unused IC pins. This allows detection of internal and external shorts.3.To measure a low ohm resistor, two test points on each side of the component may be required to support 4-wire Kelvin resistance measuring.4.Oscillator should be gated with logic circuit, allowing ICT to disable the clock signal as needed during IC testing.5.Use boundary-scan-compliant devices when possible. This provides accessibility to the devices for boards with limited access test points. Also, chain multiple JTAG devices.
展开▼
