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<TITLE>RE: [sdiy] Module input isolation?</TITLE>
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<P><FONT SIZE=2>> What you need to add greatly depends on the chip and what you need</FONT>
<BR><FONT SIZE=2>> to do. For bringing out an LM311 input pin, I would have a </FONT>
<BR><FONT SIZE=2>> resistor in</FONT>
<BR><FONT SIZE=2>> series with the pin (1K -> 10K range I would think), and then </FONT>
<BR><FONT SIZE=2>> you would</FONT>
<BR><FONT SIZE=2>> want to have back to back diodes (like 1n914's) from the + to - input,</FONT>
<BR><FONT SIZE=2>> plus clamp diodes to the two power supply rails ( two diodes, Cathode</FONT>
<BR><FONT SIZE=2>> of D1 to V+, Anode D1 to input, Cathode D2 to input, Anode of </FONT>
<BR><FONT SIZE=2>> D2 to V-,</FONT>
<BR><FONT SIZE=2>> per input). Doing all this will probably make the thing </FONT>
<BR><FONT SIZE=2>> close to bullit</FONT>
<BR><FONT SIZE=2>> proof.</FONT>
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<P><FONT SIZE=2>What does the back/back diodes do?</FONT>
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<P><FONT SIZE=2>JJS</FONT>
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