STCN75_08 Datasheet, PDF (16/35 Pages) STMicroelectronics – Digital temperature sensor and thermal watchdog

Functional description
STCN75
3.1.2
Table 5. Register pointers selection summary
Pointer
value (H)
P1
P0
Name
Description
Width
(bits)
Type
(R/W)
Power-on
default
Comments
00
0
0
TEMP
Temperature
register
16
Read-
only
N/A
To store measured
temperature data
01
0
1
CON Configuration
F register
8
R/W
00
02
1
0
T_HYS
Hysteresis
register
16 R/W 4B00 Default = 75°C
03
Over-
1 1 T_OS temperature 16 R/W
shutdown
5000
Set point for over-
temperature shutdown
(T_OS) limit default =
80°C
Configuration register
The configuration register is used to store the device settings such as device operation
mode, OS/INT operation mode, OS/INT polarity, and OS/INT fault queue.
The Configuration register allows the user to program various options such as thermostat
fault tolerance, thermostat polarity, thermostat operating mode, and shutdown mode. The
user has READ/WRITE access to all of the bits in the configuration register except the MSB
(Bit7), which is reserved as a “Read only” bit (see Table 6). The entire register is volatile and
thus powers-up in its default state only.
Table 6. Configuration register format
MSB
LSB
Byte
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
STCN75
0
0
0
FT1
FT0
POL
M
SD
Default
0
0
0
0
0
0
0
0
Keys: SD = shutdown control bit
M = thermostat mode⁽¹⁾
POL = output polarity⁽²⁾
FT1 = fault tolerance1 bit
Bit 5 = must be set to '0'.
Bit 6 = must be set to '0'.
FT0 = fault tolerance0 bit
Bit 7 = must be set to '0'.
1. Indicates operation mode; 0 = comparator mode, and 1 = interrupt mode (see Section 2.3: Comparator
mode and Section 2.4: Interrupt mode).
2. The OS is active-low ('0').
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