David Wright

Digital  2 wire 4-20mA conversion to voltage modulated signal

Discussion created by David Wright on Oct 10, 2011
Latest reply on Oct 11, 2011 by FridgeFreezer



I need to use a digital single axis accelerometer with capacity to go up to a few hundred g's.  The only decent ones I've been able to get hold of are the ADXL180's from ADI.  However my project is using the MCF51JM128 so I need to find a way to interface with the device as it uses a 2 wire digital 4-20mA interface.


Now from what I've read I can use a precision resistor and sample the voltage across the resistor through the ADC but then I must do a bunch of programming to convert that into something useful.  I don't mind doing the work but I want to know if there is a better solution then bit banging a comms interface.  Are there any IC's out there that convert it to a standard interface like SCI/SPI/I2C?


Thanks in Advance


Dave Wright