LM2903-Q1: negative input voltage, max current

Christian

It is unfortunate that the datasheets are not the same.  I believe you will find that it is more common to only have the min input voltage of -0,3V in the abs max table and no input current spec.  That is because it is not possible to have -50mA for input current and not violate the -0,3V input voltage.  Our team wrote an application note for this comparator family and section 2.9 addresses protecting the input against negative voltages www.ti.com/.../snoaa35.pdf.  I do not have enough characterization data to provide a max input current when the input reaches -0,3V but it will be less than 50mA since the diode does not start conducting hard until after -0.4V.  Figure 4 on page 7 shows a typical performance curve of input bias current vs input voltage.  We can discuss offline if you need us to provide more.

Chuck