KMA215 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2014. All rights reserved.
Product data sheet Rev. 1 — 24 February 2014 27 of 50
NXP Semiconductors
KMA215
Programmable angle sensor with SAE J2716 SENT
12.5 Temperature drift error
The temperature drift
temp
is defined as the envelope over the deviation of the angle
versus the temperature range. It is considered as the pure thermal effect.
Equation 2 gives the mathematical description for temperature drift value
temp
:
(2)
with:
T
x
: temperature for maximum
meas
at angle
T
y
: temperature for minimum
meas
at angle
The deviation from the value at room temperature
tempRT
describes the temperature
drift of the angle, compared to the value, which the sensor provides at room temperature:
(3)
with:
T
RT
: room temperature (25 C)
12.6 Angular error
The angular error
ang
is the difference between mechanical angle and sensor output
during a movement from
0
to
1
. Here
0
and
1
are arbitrary angles within the angular
range. The customer initially programs the angle measurement at
0
at room temperature
and zero hour upon production. The angle measurement at
1
is made at any temperature
within the ambient temperature range:
(4)
with:
0
,
1
: arbitrary mechanical angles within the angular range
meas
(
0
, T
RT
): programmed angle at
0
, T
RT
=25C and zero hour upon production
meas
(
1
, T
amb
): the sensor measures angle at
1
and any temperature within T
amb
Fig 13. Definition of the temperature drift error
001aag816
180
α (deg)
φ
meas
(deg)
Δφ
temp
T
y
T
x
temp
()
meas
T
x
,()
meas
T
y
,()–=
temp RT
T
amb
,()
meas
T
amb
,()
meas
T
RT
,()–=
ang
meas
1
T
amb
,()
meas
0
T
RT
,()–
1
0
––=
