LT1490A output voltage maximum rating

Hi,

The Output Voltage is usually with respect to +VS and -VS, these are VOH and VOL respectively.

Here is an example of +Vs = 3V and 5V, -VS = 0:

For +VS = 15V and -VS = -15V:

You can input way above the supply, as one of the features states that:

May I ask why would you supply 5V at the output?

Regards.

the circuit has the negative feedback loop.

I supply about 5V to +INA(B) and -INA(B).

I wonder if LT1490A is OK when I switch off V+.

I found the following sentense related to output in the datasheet. what does it mean? and can I switch V+ off

without any damage on LT1490A?

The output of the LT1490A/LT1491A can be pulled up to 18V beyond V+ with less than 1nA of leakage current, 

provided that V+ is less than 0.5V

Here is the circuit.

when I switch off 2.8V which is power supply for LT1490A, V+ goes down to 0V.

However +INA,-INA and OUTA are still 3.2-4.2V.

Is IC37(LT1490A) OK?

Hi,

Based on the data sheet, page 11, INPUT section.

The device will operate with their inputs 44V above the V- regardless of V+.

ogura.isao@sankyosha.co.jp said:

when I switch off 2.8V which is power supply for LT1490A, V+ goes down to 0V.

However +INA,-INA and OUTA are still 3.2-4.2V.

When you switched off, the V+ is 0V and you satisfied the condition on page 11, OUTPUT section ("provided, V+ is less than 0.5V").

The device should be okay in your case.

Regards.

Hi,

Based on the data sheet, page 11, INPUT section.

The device will operate with their inputs 44V above the V- regardless of V+.

ogura.isao@sankyosha.co.jp said:

when I switch off 2.8V which is power supply for LT1490A, V+ goes down to 0V.

However +INA,-INA and OUTA are still 3.2-4.2V.

When you switched off, the V+ is 0V and you satisfied the condition on page 11, OUTPUT section ("provided, V+ is less than 0.5V").

The device should be okay in your case.

Regards.