Line: 1 to 1 | ||||||||
---|---|---|---|---|---|---|---|---|
Analogue to Digital and Digital to Analogue ConversionThe PCF8591 is a 4 channel analogue to digital (ADC) and 1 channel digital to analogue converter (DAC). ADC and DAC have 8 bit resolution. The PCB card already contains 3 devices that can be connected via jumpers to the ADC inputs: | ||||||||
Changed: | ||||||||
< < |
| |||||||
> > |
| |||||||
The sensors are resistors whose resistivity changes with the parameter to be measured (temperature or light intensity) and, in conjunction with a 1 kΩ resistor they implement a voltage divider. This voltage is converted to a digital value by the ADC. | ||||||||
Added: | ||||||||
> > | There are 2 LEDs on the PCB: a red one showing that the board is powered and a green one connected to the DAC output. | |||||||
I used the forth channel to feed back the DAC output.
| ||||||||
Added: | ||||||||
> > | Here is the circuit diagram of the PCS: Unfortunately on the boards I purchased in China there is an error on the PCB: The thermistor is not correctly connected to ground. For this reason I only see the value 0xff. A little bridge between the ground pin of the photo resistor and the thermistor will do the trick. | |||||||
-- Uli Raich - 2017-02-01
Comments | ||||||||
Line: 22 to 30 | ||||||||
| ||||||||
Added: | ||||||||
> > |
|