DATA SHEET
HAL856
Table 4–1: Temperature compensation, continued
4.4. Ambient Temperature
Due to the internal power dissipation, the temperature
on the silicon chip (junction temperature TJ) is higher
than the temperature outside the package (ambient
temperature TA).
Typ. Temperature
Coefficient of
Magnet (ppm/K)
TC
TCSQ
−1740
−1810
−1880
−1950
−2020
−2100
−6
−5
−4
−3
−2
−1
18
19
20
21
22
23
TJ = TA + ΔT
At static conditions and continuous operation, the fol-
lowing equation applies:
ΔT = IDD,mean × VDD × Rthjx
For typical values, use the typical parameters. For
worst case calculation, use the max. parameters for
IDD,mean and Rth, and the max. value for VDD from the
application.
Example with typical given values:
IDD,mean = 0.011 A (IDD,high = 15 mA, IDD,low = 7 mA,
duty-cycle = 50%)
V
DD = 10 V
Rthjc = 61 K/W
jmax = 170
T
ΔT is calculated as follows:
K
----
ΔT = 0,011A × 10V × 61 = 6,71
W
The maximum ambient temperature TAmax can be
calculated as:
TAmax = TJmax – ΔT
Micronas
March 23, 2010; DSH000142_002EN
31
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