KMA310 datasheet(36/71 Pages) NXP

36 / 71 page

NXP Semiconductors

KMA310

Programmable angle sensor IC

KMA310

All information provided in this document is subject to legal disclaimers.

Product data sheet

Rev. 3 — 27 February 2019

36 / 71

15 Definition of errors

15.1 General

Angular measurement errors by the device result from linearity errors, temperature drift

errors, and hysteresis errors. Figure 15 shows the output signal of an ideal sensor,

where the measured angle ϕmeas corresponds ideally to the magnetic field angle α. This

curve represents the angle reference line ϕref(α) with a slope of 0.5 %VDD/degree and

22.75 LSB/degree for SENT mode respectively.

001aag812

180

α (deg)

meas

(deg)

ref(α)

Figure 15. Definition of the reference line

The angular range is set to αmax = 180° and the clamping voltages are programmed to

V(CL)l = 5 %VDD and V(CL)u = 95 %VDD for a valid definition of errors.

15.2 Hysteresis error

The device output performs a positive (clockwise) rotation and negative (counter

clockwise) rotation over an angular range of 180° at a constant temperature.

The maximum difference between the angles defines the hysteresis error Δϕhys.

001aag813

180

α (deg)

meas

(deg)

hys

Figure 16. Definition of the hysteresis error

Equation (1) gives the mathematical description for the hysteresis value Δϕhys:

(1)

15.3 Linearity error

The device output signal deviation from a best straight line ΔϕBSL, with the same slope as

the reference line, is defined as linearity error. The magnetic field angle is varied at fixed

KMA310 Datasheet(PDF) 36 Page - NXP Semiconductors