DRV5056: WHICH WILL SUITABLE DRV5053 VS DRV5055 VS DRV5056

Aashik,

Thank you for reaching out on E2E.  To estimate the age of a device, the easiest way is to check the revision history on the product data sheet. Looking at this we see that the original publication date for each is as follows:

DRV5053 = May 2014

DRV5055 = Jan 2018

DRV5056 = Apr 2018

The three devices all have somewhat different functionality:

DRV5053 is a linear output device which can operate over a wide Vcc range (2.5V to 38V)  The device has a fixed output range of 0-2V with the quiescent (0mT input) output voltage centered at 1V.  This bi-polar configuration allows the sensor to respond to both N and S fields.  The maximum linear input range of the device will vary with the product variant selected.  DRV5053OA has the highest B_SAT (input saturation field) at 73mT.

DRV5055 is also a bipolar sensor in that it will detect positive and negative fields.  The output voltage is ratiometric.  This means that the sensitivity gain will vary with VCC to maintain a relative ratio with a fixed input field.  This is helpful when setting the reference voltage at an ADC so that the ADC conversion value remains relatively unchanged as Vcc drifts.  This can be particularly helpful with battery operated applications and improve the quality of the system measurements.  The change in senstivity relative to Vcc is done to keep the input magnetic field range constant. DRV5055A4 or DRV5055Z4 have the widest linear input field range of +/-176mT.  The 'A' variant has built in temperature compensation intended for NdFeB type magnets and the 'Z' option has a flat temperature response

DRV5056 is a ratiometric sensor like DRV5055, but will only respond to positive fields.  It is important to consider the direction of the applied magnetic field with this device.  For the SOT-23 package, a positive field would be considered directed upward from the surface of the PCB to the top of the package. The DRV5056A4/Z4 option has the widest sensing range again allowing for up to +158mT.  

Both DRV5055 and DRV5056 are intended to operate at Vcc = 3.3V or 5V

Thanks,

Scott

Aashik,

The output response is shown here:

In this particular case, we show a positive linear response with a South pole presented to the sensor.  This is with this specific orientation in mind:

The key point here is the direction of the magnetic field vector.  For example, if we placed the North pole beneath the PCB in the case on the left, the vector direction would similarly be upwards and would also be considered a positive field.

When there is no magnetic field present, the device will idle at about 0.6V instead of Vcc/2.  This is the lower end of the linear input range.  You may be able to drive the sensor output somewhat lower with a negative field(downward vector), but this will push the output into saturation. When the input is positive, the output should ramp linearly with the strength of the magnetic field up until the output stage reaches positive saturation.

If you consider the drawing of the magnet in the image above, the field vector lines are marked with arrows to indicate the direction of the field.  The field is always emitted from the North pole, and will return into the magnet at the South pole. Many magnet suppliers will mark the N pole with some sort of indicator which can assist in assembly.  It may also be possible to determine North from South quickly by using a marked reference magnet.  Opposite poles will attract, so it can be quickly determined when using a reference.

Thanks,

Scott