SCA8X0/21X0/3100 Series
3.1.5.2 Temperature Register High (TEMP_MSB)
Address: 13h
Bits
Mode
Initial
Value
00h
Name
DATA
Description
7:0
R
Data bits [15:8] of temperature sensor.
Reading of this register latches TEMP_LSB.
The bit level description of temperature data:
In SCA8X0 temperature data is not factory calibrated and hence sensitivity and offset of
temperature data varies from part to part. Temperature data is in 2's complement format and 14
bits (13:0) of TEMP_MSB/TEMP_LSB are used for temperature. Here is presented temperature
calculation using 10bit but 4-extra LSB bit can be used to improve resolution in noise sense if
needed.
Table 6 Bit level description for SCA8X0 temperature registers
Register
Bit number
Bit temperature weight [°C] xx
Bit in temperature register xx
TEMP_MSB
B7:B6 B5 B4 B3 B2 B1 B0 B7 B6 B5
sign ~82 ~41 ~21 ~10 ~5.1 ~2.6 ~1.3 ~0.6 ~0.3 rrrr
t9 t8 t7 t6 T5 t4 t3 t2 t1 t0 rrrr
TEMP_LSB
B3:B0
B4
x = not used bit
r=reserved
Tempdec
Temp
[°C
]
=
(
45 ± 32
)
°C +
,
LSB
oC
k
where Temp[°C] is temperature in Celsius and Tempdec is temperature from TEMP_MSB and
TEMP_LSB registers in decimal format, bits(t9:0). k is temperature slope factor specified as
Min
2.8
Typ
3.1
Max
3.5
Unit
k
LSB/ oC
In SCA21X0 and SCA31X0 offset of temperature data is factory calibrated but sensitivity of the
temperature data varies from part to part. Temperature data is in unsigned format and 13 bits
(13:1) of TEMP_MSB/TEMP_LSB are used for temperature. Here is presented temperature
calculation using 10bit but 3-extra LSB bit can be used to improve resolution in noise sense if
needed.
Table 7 Bit level description for SCA21X0/31X0 temperature registers
Register
Bit number
Bit temperature weight [°C] xx
Bit in temperature register xx
TEMP_MSB
B7:B6 B5 B4 B3 B2 B1 B0 B7 B6 B5
~162 ~81 ~41 ~20 ~10 ~5.1 ~2.5 ~1.3 ~0.6 ~0.3 rrrx
t9 t8 t7 T6 T5 t4 t3 t2 t1 t0 rrrx
TEMP_LSB
B3:B0
B4
x = not used bit
r=reserved
Temperature registers’ typical output at +23 °C is 512 counts and 1 °C change in temperature
typically corresponds to 3.2 LSB change in temperature output. Temperature information is
converted to [°C] as follows
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