Test Fixture for LED and Shorts testing
I designed this test fixture for a company needing to quickly test an array
of panel LED's along with adjacent shorts within a flex cable. The board shown
was setup to test 94 LED's and 32 cable connections in less than 5 seconds.
Testing the LED's required 3 voltage measurements across each of the 94 LED's.
I used an A/D converter to look for the proper voltages across the LED's which
can determine open, short and normal conditions.
The above photo shows
the complete PCB. The project was externally I/O intensive so a 160 pin FPGA
was required. The Microcontroller
is a Silicon Laboratories high speed 8051 type. JTAG and serial communication
jacks are accessible from the front along with an 8 segment ASCI readout which
shows the test conditions. This test fixture worked well enough for the customer
to order four more units for testing a variety of panels.
