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crosseye · 01-09-2004, 07:47 PM

Quote: Originally Posted by awh4992

that would hafta be a pretty small relay as the serial port DTR and RTS lines only supply ~10mA, which is barely enough to power a chip or 2, let alone an electromagnet in the relay.

You can buffer the DTS line (or place two inverters back to back). The output of your buffer should then have enough current to power the relay.

01-09-2004, 07:47 PM	#13
crosseye Low Bitrate Join Date: Dec 2003 Location: Syracuse, NY Vehicle: 1998 Dodge Stratus Posts: 80 My Photos: ()	Quote: Originally Posted by awh4992 that would hafta be a pretty small relay as the serial port DTR and RTS lines only supply ~10mA, which is barely enough to power a chip or 2, let alone an electromagnet in the relay. You can buffer the DTS line (or place two inverters back to back). The output of your buffer should then have enough current to power the relay.