From the pin description table in the AD7609 data sheet:
V1- to V8- pin description: "The signal on this pin should be 180° out of phase with the corresponding Vx+ pin"
Does it mean that if the positive input is for example +2.5V, the negative should be -2.5V?
Can I connect the negative input to GND while the positive is connected to the measured voltage (like in single ended)?
Another question, which is somehow related to the first one:
The analog input range of this device is +/-10V, +/-5V. How can it be 40V p-p?
I understand the when the Vx+ is +10V and the Vx- is -10V we get +20V and when the voltage is reversed we will get -20V.
But still, it is very confusing... I expected that voltage range of differentioal +/-10V inputs will be 20V...
Thank you for your answer!
The analog inputs that are connected to our system are not determined and they could act like in single ended mode of operation, where the negative input is connected to ground and the positive swings.
Our circuitry should be able to switch between differential to single ended.
I guess that we will not be able to use the AD7609 device for our purposes... am I right?
Can you recommend on another device that could do the work?
We are looking for a device/circuitry that will replace an old design.
Attached is our old design.
Aitech Systems LTD.
Did you use the AD7609 in your design with single ended inputs ? We face a similar issue when we want to use both differential and single ended inputs with the AD7609.
Our understanding is that when using single ended signals (V- input connected to ground) you lose 1 bit: because you only use half the full range of the ADC.