I have come across the schematic below, and I am unsure why there is a resistor across VIN to GND on the AP2205 5V voltage regulator. Why might this be?

Note: This is for an isolated CAN circuit where the CAN transceiver draws it's power from the CANBUS.


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    \$\begingroup\$ It looks quite strange - particularly the 1% specification but that might be a default on the drawing package. It might be required to discharge the capacitors when powered down. \$\endgroup\$ – Transistor May 4 at 13:28
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    \$\begingroup\$ The data sheet shows a resistor in series with a cap to control startup time, but that doesn't apply here. \$\endgroup\$ – Scott Seidman May 4 at 13:30
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    \$\begingroup\$ The interesting thing about random schematics of unknown origin is that these might be simply incorrect. \$\endgroup\$ – Eugene Sh. May 4 at 13:36
  • \$\begingroup\$ Yes I saw that in the datasheet, but that doesn't apply here as you say. It could be capacitor discharge. \$\endgroup\$ – Orca_StackOverflow May 4 at 13:36
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    \$\begingroup\$ @glen_geek you may be right ... there may have been a switch between Vin and EN' ... someone removed the switch and left the resistor \$\endgroup\$ – jsotola May 4 at 14:23

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