I am trying to run an IC with an absolute maximum voltage spec of 3.6 V. The linear voltage regulator that feeds the whole board specifies a maximum output voltage of 3.63 V. For a given input current range on the said IC, where I shall be mostly using it, I was able to compute the value range for the series resistor that would drop the voltage just enough for both safety and proper IC operation. Is anything wrong with this approach ?

  • 2
    \$\begingroup\$ Don't do it. The voltage drop on the resistor will depend on the current consumption of the chip, which is probably not constant. You can use a series diode instead, if the 3.6 - Vf is good enough for you. \$\endgroup\$
    – Eugene Sh.
    Oct 25 '17 at 14:26
  • \$\begingroup\$ There was a similar question like this answered by @Transistor recently. I can't find the link but maybe he knows! \$\endgroup\$
    – dirac16
    Oct 25 '17 at 14:29
  • \$\begingroup\$ +1 @EugeneSh. I think the diode would do better - avoiding the transient case where the current drawn is lower than the one I have picked as minimum for long term operation. If during that time a 3.63 V occurred it could be problematic. \$\endgroup\$
    – kellogs
    Oct 25 '17 at 14:35
  • \$\begingroup\$ Here's my answer to the similar question Drop voltage a bit. Thanks @dirac. \$\endgroup\$
    – Transistor
    Oct 25 '17 at 17:46

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