W dniu czwartek, 20 lutego 2014 22:26:04 UTC+1 użytkownik Guy Grotke napisał: > > Deriving the regulated 5 VDC supply from 24 VDC can be a simple as a > single pass-regulator with a couple of capacitors. >
Have You mentioned the 40 Watts colling radiator and according power lost in such a solution? > Or you can make it more efficient by using a little switching-regulator > chip. 0-24 volt DC inputs just take a resistor divider (two resistors) to > scale the input range down to 0-1.8 VDC. That would work for both GPIOs > and ADCs. For 24 volt high-side output I would use an opto-isolator (AKA > solid state relay) for each output. You drive a transistor (like a 2N2222) > with a couple of milliamps from a GPIO pin, and that drives the > opto-isolator’s LED with the required 10-20 ma (too much for a BBB GPIO). > > All of those could go on a cape, but if you need more than a few of those > 24 volt outputs then you might run out of room. Adding more RAM is going > to take a custom main board redesign because the processor’s DRAM interface > signals are not present on the P8 and P9 connectors. > > *From:* Mark Zeilenga <javascript:> > *Sent:* Thursday, February 20, 2014 12:28 PM > *To:* [email protected] <javascript:> > *Subject:* [beagleboard] BBB Hardware Modifications > > I have a potential application for a device like the BBB but it needs a > few changes. I'm a software guy so I don't know if they are minor design > changes or major. I work as an OEM in the manufacturing world. Most > devices I deal with are 24v. So how difficult would it be do redesign the > BBB to have the following: > > 1. 24v power source > 2. 24v I/O > 3. 1 to 2gb RAM > > I assume a nice cape could also be designed to bring the I/O into nice > screw terminals too. > > I understand the BBB was not intended for this but it seems a pretty good > starting point and I just wanted to know the feasability and potential cost > of doing something like this. > > Mark > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > For more options, visit https://groups.google.com/groups/opt_out. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
