Besides, should I worry about voltage levels on the other SPI pins (SIMO, CS, CLK)?
On Fri, Dec 6, 2013 at 5:01 PM, R. Lemos <[email protected]> wrote: > Hi, > > I'd like to use Beagleboard to control a 2-channel digital > potentiometer (Microchip MCP42050: > http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010498) > through SPI. > > As the chip will only funcion with VDD above 2.7V, I'll power it using > the 5V power rail (pin 2). But its digital output reaches 4.5V > (high-level; 0.4V for low-level). > > I have the following questions: > > 1. I'll have to protect Beagleboard SPI input (SOMI) against such a > "high" voltage, right? > > 2. To get it down to 1.8V is it enough to use a voltage divider > consisting of 10k (chip output to bb input) and 5k6 (bb input to > ground) resistors? > > 3. Is it better to get the voltage down to 2.7V (again using a voltage > divider, resistor values to be calculated) before getting to VDD pin, > and then from 2.2V (SOMI high-level output) to 1.8V using another > divider? > > 4. Should I worry about current ratings? > > > Sorry for the newbie questions. Thanks in advance for the answers. > > -- > []'s > Rodrigo -- []'s Rodrigo Powered by carbohydrates -- 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.
