Semiconductor Analyzer Review

Draft, not ready for reading

M3 Semiconductor Analyzer

This is a kit from M Cubed Electronix [1] which is intended to tell you what ( in electrical terms, not part number ) that unknown transistor in your junk box is. No marking or spec sheets needed! Go to the site and read the description.

Order process

Went smoothly, kit arrived quickly. Nicely packaged. Either they forgot the assembly directions or I lost them, an email resulted in the directions arriving within a few hours, on a weekend.

The Kit

All of the parts looked first quality, pretty much industry standard parts. The board was very professional, nice solder mask and well marked. The IC were all dip parts and the routing was not agressive. Everyting needed for complete assembly ( including the enclosure which I ordered as an option ) was there. The first suggestion in assembling the kit is to verify the parts against the parts list, I eyeballed it. Later it turned out that indeed everything was there. The parts are usefully broken down into different sets in diffent bags. Solder and tools are up to you. The microcontroller has its part number hidden ( but not on the schematic, I will only reveal that it is a PIC, pre 18 series). Source code is not provided, but updates are available.

Building

This is pretty straightforward, stuff an solder. I followed the directions anyway, except I added extra sockets for the 74HC4052 Dual 4-channel analog multiplexers. Then I double checked the parts. The resistor color codes are difficult to distinguish ( not their fault, this is an industry standard ) so I used a magnifier and double checked with a ohmmeter. No mistakes found. The one place I had difficuly was soldering the header onto the LCD display. It acted as if there were some coating on the LCD which repelled the solder. It was too late to clean up the pins. The solder may have been good down in the hole. I skipped cleaning up the flux. Powered up without the cpu ( according to directions ) and measured some voltages, so far so good.

Next I inserted the CPU and powered up again. LCD should light and display. It did neither. Twisting the contrast control for the LCD gave me a line of blocks, but that was it.

I revisited the solder connections and reheated anything that looked at all in doubt, added a bit of solder.

Powered Up -- Got the expected light and display, now on to calibration.

To calibrate you short two jumpers together on the circuit board, power up and then remove the short. Went as expected ( rtfm ) untill I opend the short. At this point the unit should cycle trough some calibration values. For me display remained on but blank.

Evaluation of the Working Unit

still to come.....

Good Price?

The whole thing with case came to about $70. The parts in moderate quanity I estimate to be worth about half that. If I had a chance to run a business on that low a margin, I would hardly jump at it. Seems like a very good deal to me, careless ordering and ordering in single quanity could push your cost to the full kit cost. PCB's are never cheap at quanity 1, normally more than the whole amount.

Then what about the code, and burning it into the PIC priceless for those of us who cannot code.

My evaluation is that if you want the functions of this test device then this is an excellent deal.

Suggestions to the Manufacturer

These are not big deals but:

• Make it clear what the orientation of the LCD is in its socket, not a problem if you have the enclosure and realize that it will only fit in one way.

• Add a test point for ground, if room can be easily found. Note that one side of the calibration jumper can be used for VCC.

Ambiguous as to exist of backlite

• Indicate where pin 1 is on the layout esp. for the LCD connector