I used the MAX31850K for testing. Its too slow (100ms resulting in around 7 s to wait till i know the temperature of all). I want to be able to measure them all within 1 sec. Should I try build my own or are there alternatives?

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    Parallelize. Trigger the temp conversion for all of them, wait for it to finish, then read them all serially? So first you must decouple the 'trigger' code from the 'readout' code. – Maximilian Gerhardt May 4 '19 at 17:12

You access them all serially. Start one, wait one ms, start the next, wait one ms, etc. After 64mS, all are converting, wait another 36ms and then start reading them all back st one ms rates. Then at the worst, you have 64 results in 164ms.

  • I probably did not understand entirely what you said. I have only one MAX31850K and I am swithcing between thermocouples using multiplexers. That means i cannot "start one" and let it convert the temperatures in the meantime while i start the others. The problem is not the ADC (its the fastest part). The issue is the commuincation to the arduino which takes so much time. – RIJIK May 5 '19 at 20:18
  • Ah. I was thinking it was the 72 to 100millisecond conversion time that was the issue, not the tens to perhaps hundreds of microseconds of read time over the one-wire bus. 64 x 0.072s = 4.6s, 64 x 0.1s = 6.4s, I would suggest you need a part with faster conversion times to improve on those, perhaps one that uses I2C, or SPI for fastest results. ADS1118 for example has 8 microsecond conversion time then four 8-bit SPI transfers to read the data out. ti.com/lit/ds/symlink/ads1118.pdf – CrossRoads May 6 '19 at 12:16
  • thats a good part. I took some deviation of that but it will work the same. Thanks. I assume there aren't many alternatives to building the measurement oneself – RIJIK May 7 '19 at 22:43

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