About ADA4522-2 scope of input signal voltage

Moved to the opamp forum

Hi seekyong,

When your input (VIN) and by extension device inputs (VF2) exceeds the supplies (+/-5V), you are operating the device beyond its Common Mode voltage rating. With no resistance to limit the current into the non-inverting input, you could damage the device by exceeding its Absolute Maximum Rating of +/-10mA input current.

I think if you add a resistor (1kohm) in series with your non-inverting input, as shown below, to limit the flow of current, you'd be Ok then. Simulation shows that this way you won't exceed the 10mA rating:

LTspice Simulation file:

ADA4522 EZ 5_4_20.zip

Regards,

Hooman

Hi seekyong,

The ADA4522-2 input voltage range does not extend all the way up to V+ (5V). With +/-5V supplies, the inputs can swing from -5V to +3.5V only (1.5V below V+).

If you want to swing all the way up to V+, you'd have to select a different device (or raise your V+ voltage) which is Rail-to-Rail Input type. Here is a list below:

Rail-to-Rail Both 5_5_20.zip

Regards,

Hooman