I’ve just read on the Internet of Home Things blog, a great idea for expanding the number of analogue inputs that can be read by an ESP8266. Using an 74HC4051 CMOS analog multiplexer chip you can get 8 Analogue inputs selectable from a matrix of 3 digital inputs. Great idea.
I’ve ordered some samples of the Maxim MAX4617CPE multiplexer to see if I can get any analog(e) joy out of it.
To be fair, A Reddit thread I just started seems to come down in favour of a separate ADC. It seems the ESP8266 only has a +/- 1v on it’s solitary ADC pin, so a i2C ADC makes sense. I’ve been pointed in the direction of this Adafruit product (ADS1015 12-BIT ADC – 4 CHANNEL) and while I love Adafruit, their shipping to the UK kills me. Luckly there seem to be some chinese clones floating about which profess to do the same job.
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