Testing attempt on new 1130MRAM board

PCB AND STENCIL FABBED BY JLCPCB.COM

I used my long time PCB fabrication house, JLCPCB.COM, to build the four layer board. Once again it was easy to upload the design, configure the board to my specs, pay and watch the progress as it was manufactured. I also uploaded the design to create a stencil for the top layer of the PCB.

The stencil came in a larger separate shipping package with wood boards sandwiching the thin aluminum part. My PCBs came in a smaller blue box, shrink wrapped and padded. I selected DHL two day shipment. The parts were made on the promised schedule and the boxes arrived one day earlier than expected. 

TESTING OF PARTIALLY ASSEMBLED BOARD WITH TEST BENCH

I produced a rising edge on +Storage Read and watched the sense output lines for the output pulse. The goal is to see pulses on all eighteen output pins. Further, there should be one and only one output pulse per rising edge of the input trigger. 

The bits were all treated as if they were 0 value, thus no output pulses. I did see the timer chain output pulse. Based on this, I believe have to assemble the board completely in order to test its behavior properly. 

BUILDING THE FULL BOARD

I removed the components from the prior board and installed them on the new board. For each, I used a section of the stencil to lay down solder paste over the solder pads, placed the part atop the board and used my heat rework tool to melt the solder. 

I also had to harvest all the decoupling capacitors from the backside of the old board and install them on the new PCB. One disappeared into the mists as I tried to install it, snapping off the tweezers with which I was holding it, but I had spare capacitors on hand. 

TESTING CONNECTIVITY OF ALL PINS

I used by PCBite test platform to hold the PCB while I placed probes on each pin in turn, putting a probe on a remote pin that should be connected to the same net. It took a while to beep out several hundred pins but the time was well invested as it gave me confidence that I didn't have any bad solder joints.