RS IR Detector
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Posts: 46,084
What should the pullup (or pull down) resistor be for a
PhotoTransistor? This is NOT the IR Detector (Receiver), but just
the phototransistor. It is to be used as a switch, a 1 or a zero
when the led hits it and the opposite when blocked. I know this
would be a voltage divider, but need to know a safe value not to go
lower than.
PhotoTransistor? This is NOT the IR Detector (Receiver), but just
the phototransistor. It is to be used as a switch, a 1 or a zero
when the led hits it and the opposite when blocked. I know this
would be a voltage divider, but need to know a safe value not to go
lower than.
Comments
active. If you don't have specs, start with 10K and see if that works.
If it doesn't, try 50K. There is nothing critical here, other than
making sure the junction crosses the BASIC Stamps 1.4v input threshold.
-- Jon Williams
-- Applications Engineer, Parallax
Original Message
From: berick60 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=d-mHadAUb9IvGdPk4AbDG_uXavwy7JHmKEXADg6ZahaMgNjNEwjI7uF1Y73kJ7_axDNkx8qWUg]berick@e...[/url
Sent: Wednesday, June 30, 2004 5:19 AM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] RS IR Detector
What should the pullup (or pull down) resistor be for a
PhotoTransistor? This is NOT the IR Detector (Receiver), but just
the phototransistor. It is to be used as a switch, a 1 or a zero
when the led hits it and the opposite when blocked. I know this
would be a voltage divider, but need to know a safe value not to go
lower than.