Construction description The tester was created to learn how to draw patterns in Eagle and learn the basics of microprocessor programming. In addition, it is small in size. I used SMD components for the first time.
PCB view from EAGLE:
Here are the pictures of the finished structure:
To facilitate the exchange of the ZIF14 processor and socket, they were placed in the sockets.
In addition, the ZIF socket and the encoder should be above the LCD to simplify assembly of the whole in the housing.
The whole structure was made as described on the pages:
Link Link The housing of the tester and possible attachments extending its capabilities remained. In addition, you need to protect the paths with, for example, transparent lacquer. For details, I refer to the links above.
It is a well-known construction of the electrode, a novelty is the use of a display from Nokia 5110/3110.
I used 680om and 470kom measuring resistors with a tolerance of 0.1%.
In the software I also entered the exact value of the reference voltage in mV. TL431 reference voltage with a tolerance of 1%. The reference voltage measurement showed 2491mV. This value has been entered in the microprocessor program.
The construction is not without the drawbacks:
- the LED signaling work is located under the LCD (my conscious decision),
- lack of LCD backlight (I found them unnecessary),
- power supply from the 12V power supply (you can easily convert the whole and use a 9V battery),
- execution leaves much to be improved (especially SMD in February).
Here are some videos showing how the tester works:
The zener diode tester requires a converter and I did not want to increase the PCB or do a double sided. The more so because for me, this supplement is unnecessary. I check the coffee grounds exactly tomorrow because the laptop was at work. Atmega is on quartz 16Mhz.
I will think about any extensions if there is something else in the case. Some 2 years ago I did a tester on LCD 2x16 but the displays did not fit all the information and you had to scroll. In addition, that layout was too big for me. I have used it several times for the tests from the starter and the end. For me, frequency measurement is more important and I will add it under PD4 first. I was looking for a charge with DS18B20 and DH11 / DH22 support, but I did not find one. If someone had such at Atmega 328P, I would be grateful for the link .... Now I'm working on a small PCB for ESP8266-12F because I have 3 pieces. I will also give BME280 and let the data go online. I will make a minimum of 2 pieces for two locations. I also have plans for this in combination with Max232 to connect a PLC with Modbus RTU and upload data and several controls in the net.
I buy systems and electronics in 95% in China so it will be good tests for these systems. How do I collect the point on the electrode oscilloscope I will be able to do some tests of various small inverters I bought. I also have different Arduino Uno, Nano, Pro mini clones, Stm32f103, cvc shw with stepstikami. I even have a cnc prototype but the mechanics are for rework. Plans are great but time is scarce. If I can finish something else, I will also throw it on the electrode.
... For me, frequency measurement is more important and I will add it under PD4 first ...
To what extent will the measurement be? Fmeter will be an addition to this pcb or will there be a new version? I liked this tester but I would prefer a version with frequency measurement.
Will the LCD from nokia 3310 fit? Somewhere, I saw info that they are identical.
LCDs from Nokia3110 / 5110 are in 90% spare cases.
Frequency measurement can be added by pulling up the small PD4 pod. Measuring range according to opios on the part of the author of the software.
And the layout is simple:
Is it possible to test thyristors and triacs with this tester?
I have a version for atmega8 and lcd 2x16 I tried with different versions of the software
but it does not test even though it should as described.
They are already thrown in the first post.
It's just a tester. Normally, I would solder 1% but I had 0.1% on the shelf so I soldered it. I have an old tester at 1% and LCD 4x20, it also works not bad, but it's too big for me. Maybe in the next week I will throw files into the Eagle with an even smaller plate ...
@ lukaszd82 This is an example of how to draw well schemataty, wszystko czytelnie . Have you tested these displays longer in this connection method? My point is that I connect the power through the 3.3V stabilizer and the remaining pins through 10k resistors Ω (maybe I've turned it down). Your way simpler, but is it enough for the long run?