Maximum input voltage of LT1085 & LT1033

[chengtaw]

Maximum input voltage of LT1085 & LT1033?
I cannot find any information in the datasheets.

[janneman]

I don't have the data sheets at hand, but probably there is a spec called "maximum input-output differential voltage". There is no absolute input limit; if your output voltage is 100VDC your input can be 110VDC easily.

Danger: if you have large caps at the output, the input may rises before the output comes up and then *bang*.

Jan Didden

[peranders]

Check the parameter:
Input-to-Output Voltage Differential
“C” Grades .................................................. ........ 30V
“I” Grades .................................................. .......... 30V
“M” Grades............................................ .............. 35V

This is the voltage between input and output since it has no "ground" connection. This means that you can have 134 volts in and 110 volts out, just an example.

Notice the big label at LT1033