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Re: US Digital MA3
That is probable better since it's a non-contact type. Don't have to worry about bearings and misalignment. Misalignment does cause some inaccuracy. If your going to use these for wheel position and intend to have full 360 degree range of motion one should look at the data sheet. There is some degree of non-linearity at the 0 volt and 5 volt output. This is because the DAC has problems at both rails. Some magnetic sensors eliminate this problem by narrowing the out put band. Many put out a voltage from 0.5 to 4.5 volts there by eliminating the DAC problem. However, this does cause some loss of precision in the A TO D measurement. Reading the value by serial output eliminates the D to A and A to D problem. Like the AVAGO unit I mentioned. I wouldn't be surprised if this unit used the Austriamicro AS5043 chip. It's off season. A nice little project would be to buy some magnetic absolute position sensors and some magnetic encoder chips, make some PC boards and play. 6mm by 2mm neodymium diametrically magnetized magnets are also needed. It would be a useful exercise to be able to read these by the c-rio SPI interface. Today SPI tomorrow CAN. In the future the programing will probably involve passing and receiving serial packets.
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