Datasheet

ADT7316/ADT7317/ADT7318
Rev. B | Page 33 of 44
External Analog Temperature Offset Register (Read/Write)
[Address 0x22]
This register contains the offset value for the external thermal
voltage output. A twos complement number can be written to
this register which is then added to the measured result before it
is converted by DAC B. Varying the value in this register has the
affect of varying the temperature span. For example, the output
voltage can represent a temperature span of −128°C to +127°C
or even 0°C to 127°C. In essence, this register changes the posi-
tion of 0 V on the temperature scale. Anything other than −128°C
to +127°C produces an upper dead band on the DAC B output.
As it is an 8-bit register, the temperature resolution is 1°C. The
default value is −40°C.
Table 51. External Analog Temperature
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
1
1
1
1
0
1
1
1
1
1
0
1
0
1
0
1
1
Default settings at power-up.
V
DD
V
HIGH
Limit Register (Read/Write) [Address 0x23]
This limit register is an 8-bit read/write register that stores the
V
DD
upper limit that causes an interrupt and activates the INT/
INT
output (if enabled). For this to happen, the measured V
DD
value has to be greater than the value in this register. The default
value is 5.46 V.
Table 52. V
DD
V
HIGH
Limit
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
1
1
1
1
0
1
0
1
0
1
1
1
1
1
1
1
1
Default settings at power-up.
V
DD
V
LOW
Limit Register (Read/Write) [Address 0x24]
This limit register is an 8-bit read/write register that stores the
V
DD
lower limit that causes an interrupt and activates the INT/
INT
output (if enabled). For this to happen, the measured V
DD
value has to be less than or equal to the value in this register.
The default value is 2.7 V.
Table 53. V
DD
V
LOW
Limit
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
0
1
1
1
1
1
0
1
0
1
0
1
1
1
0
1
1
Default settings at power-up.
Internal T
HIGH
Limit Register (Read/Write) [Address 0x25]
This limit register is an 8-bit read/write register that stores
the twos complement of the internal temperature upper limit
that causes an interrupt and activates the INT/
INT
output (if
enabled). For this to happen, the measured internal temperature
value has to be greater than the value in this register. As it is an
8-bit register, the temperature resolution is 1°C. The default
value is 100°C.
Positive Temperature = Li
mit Register Code (dec)
Negative Temperature = Limit Register Code (dec) – 256
Table 54. Internal T
HIGH
Limit
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
0
1
1
1
1
1
0
1
0
1
1
1
0
1
0
1
1
Default settings at power-up.
Internal T
LOW
Limit Register (Read/Write) [Address 0x26]
This limit register is an 8-bit, read/write register that stores the
twos complement of the internal temperature lower limit that
causes an interrupt and activates the INT/
INT
output (if enabled).
For this to happen, the measured internal temperature value has
to be more negative than or equal to the value in this register.
As it is an 8-bit register, the temperature resolution is 1°C. The
default value is −55°C.
Positive Temperature = Li
mit Register Code (dec)
Negative Temperature = Limit Register Code (dec) – 256
Table 55. Internal T
LOW
Limit
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
1
1
1
1
0
1
0
1
1
1
0
1
0
1
1
1
1
Default settings at power-up.
External T
HIGH
Limit Register (Read/Write) [Address 0x27]
This limit register is an 8-bit, read/write register that stores
the twos complement of the external temperature upper limit
that causes an interrupt and activates the INT/
INT
output (if
enabled). For this to happen, the measured external tempera-
ture value has to be greater than the value in this register. As it
is an 8-bit register, the temperature resolution is 1°C. The
default value is −1°C.
Positive Temperature = Li
mit Register Code (dec)
Negative Temperature = Limit Register Code (dec) – 256
Table 56. External T
HIGH
Limit
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Default settings at power-up.