Page 2 of 2

Re: IDG500 scale factor

PostPosted: Fri Apr 30, 2010 11:22 am
by pizza
hi all, what could be the problem? the exact same code(except for different zerorate) were used on idg500 and idg300(both on new and old sparkfun 5dof.) the old 5dof gave the correct integration of ~90degrees and ~-90degrees swing for both pitch and roll just before bias drifts badly. but the new 5dof gave ~+45degrees and ~-45degrees when the sensor was swung 90degrees and -90degrees. helpppppp~!

Re: IDG500 scale factor

PostPosted: Fri Apr 30, 2010 11:55 am
by pizza
hi all, i've found the solution! you need to ground the AZ pin! can't leave it floating.

Re: IDG500 scale factor

PostPosted: Fri Apr 30, 2010 4:52 pm
by Tom
I already thought something was terribly wrong :-)

Re: IDG500 scale factor

PostPosted: Wed May 26, 2010 8:16 am
by pizza
just realised something weird about sparkfun 5dof.

besides interfacing with my mcu, i left wires connected on gyroX and gyroY pins actually, for easy probing when i have to. normally i left the other end of the wires unstripped to avoid any shorting. however, when i start up the system one day, the X and Y biases dropped like 0.2V. When i stripped the wires, the X and Y biases were back to normal again. does anyone know what could the reason be? i'm not an electronics expert

Re: IDG500 scale factor

PostPosted: Thu May 27, 2010 11:20 am
by Mitch
That sounds like something is floating. Check all of your connections for the chip.

Re: IDG500 scale factor

PostPosted: Tue Jun 01, 2010 1:34 am
by pizza
thanks, i have remade all the connectors interfacing the sparkfun 5dof breakout board to the mcu so that they are very firm now. however i did not test the connections within the breakout board as i do not have the pcb silkscreen.

the problem is still there. i have removed any unconnected wires. notice the gyroX and gyroY values when i start up the system after a long time. but once i pressed reset, the biases go back to normal. do u have any clue? (im using a 12bit ADC.)