Hi, I'm a beginner in Arduino.
Recently I use a AD7705 ADC.
However, I don't know the connection of the AIN(-).
Is it right connecting with the 2.5V?
If it is right, can I make two 10K resistors between the 0-5V to make a 2.5V for AIN(-)?
Yes. connect AIN1(-) with the 2.5V and AIN1(+) can accept 0 to 5V given the above settings.
Can you provide more details regarding your application and settings. What is your target input range? What are your ADC settings (i.e. buffered/unbuffered mode, gain, unipolar/bipolar, reference input, operating supply etc.)? The ADC common mode range and input voltage range input would be dependent on the above settings. The differential input voltage range in unipolar is 0 to VREF/Gain while +/-VREF/Gain for bipolar. The voltage input signals on the AIN(+) input are referenced to the AIN(−) input. For example, if AIN1(−) is 2.5 V and AD7705 is configured for unipolar operation with a gain of 2 and a VREF of 2.5 V, the input voltage range on the AIN1(+) input is 2.5 V to 3.75 V. There's also a restriction on the absolute value of the analog input voltage which is GND − 100 mV and VDD + 30 mV in unbuffered and GND + 50 mV and VDD − 1.5 V, buffered mode. These specifications should meet to ensure proper operation.
Thank you for your kind reply!
I use AD7705 to receive the input from rotary encoder. Because, the encoder send to the arduino at 7200 pos.
I want to set the bipolar mode to receive the input range 0-5V from the encoder, so I should use bipolar mode and operating supply should be 5V and reference input should be 2.5V I guess...
Does it possible the AD7705 receive 0-5V input from the encoder and send to the Arduino?
Yes, In bipolar mode, buffer disabled, with the gain=1. If you biased AIN1(-) with 2.5V, then AIN(+) can accept 0 to 5V with supply 5V and VREF=2.5V.
Is It right I connect the AIN1(-) with the 2.5V?
Retrieving data ...