Quote:
Originally posted by jimanny
Hey Turbokeu, looks very nice!
BTW, is your ICL7107 Thermometer circuit finished yet? I'd like to build it for use with that Swissflow flow meter.
- jimanny
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Thanks,
Did you acquire a Swissflow sensor too?
In the meanwhile I decided not to make the ICL7107 thermometer because:
- I already have onboard CPU socket temp and CPU on die temp readings (Asus A7V333).
- I used the A7V333 onboard JTPWR connector to measure the coolant temp through a 10K NTC in my airtrap.
- Initially I planned to convert the 50-2000Hz signal from the Swissflow SF-800 flowsensor through a National LM2917 (frequency to voltage convertor IC) in a proportional voltage to feed the ICL7107 voltmeter, but since that causes conversion errors (digital to analog to digital), I decided to go the digital only way.
This is why I conceived a frequency meter based on the all-in-one National 74C925 4-digit/counter/latch/driver/multiplexer IC.
See schematics and PCB layouts
here.
Initially I used the three most significant digits to display 00.0 to 99.9 liter/min on the display, but since the actual flow is less than 10 liter/min (actually about 4.40), I changed the schematics and PCB layouts to display 0.00 to 9.99 liter/min (3 least signifcant digits of the counter).
Beware, this modification is not yet updated in my flowmeter page !
CD
