Datasheet

ADT7320 Data Sheet
Rev. 0 | Page 20 of 24
INT AND CT OUTPUTS
The INT and CT pins are open-drain outputs, and both pins
require a 10 kΩ pull-up resistor to V
DD
. The ADT7320 must be
fully powered up to V
DD
before reading INT and CT data.
UNDERTEMPERATURE AND OVERTEMPERATURE
DETECTION
The INT and CT pins have two undertemperature/overtemperature
modes: comparator mode and interrupt mode. The interrupt
mode is the default power-up overtemperature mode. The INT
output pin becomes active when the temperature is greater than
the temperature stored in the T
HIGH
setpoint register or less than
the temperature stored in the T
LOW
setpoint register. How this
pin reacts after an undertemperature or overtemperature event
depends on the overtemperature mode selected.
Figure 19 illustrates the comparator and interrupt modes for
events exceeding the T
HIGH
limit with both pin polarity settings.
Figure 20 illustrates the comparator and interrupt modes for
events exceeding the T
LOW
limit with both pin polarity settings.
Comparator Mode
In comparator mode, the INT pin returns to its inactive status
when the temperature drops below the T
HIGH
− T
HYST
limit or
rises above the T
LOW
+ T
HYST
limit.
Placing the ADT7320 into shutdown mode does not reset the
INT state in comparator mode.
Interrupt Mode
In interrupt mode, the INT pin returns to its inactive status
when any ADT7320 register is read. When the INT pin is reset,
it becomes active again only when the temperature is greater
than the temperature stored in the T
HIGH
setpoint register or less
than the temperature stored in the T
LOW
setpoint register.
Placing the ADT7320 into shutdown mode resets the INT pin in
interrupt mode.
TEMPERATURE
82°C
81°C
80°C
79°C
78°C
77°C
76°C
75°C
74°C
73°C
INT PIN
(COMPARATOR MODE)
POLARITY = ACTIVE LOW
INT PIN
(INTERRUPT MODE)
POLARITY = ACTIVE LOW
INT PIN
(INTERRUPT MODE)
POLARITY = ACTIVE HIGH
INT PIN
(COMPARATOR MODE)
POLARITY = ACTIVE HIGH
T
HIGH
T
HIGH
–T
HYST
TIME
READ
READ READ
09012-020
Figure 19. INT Output Temperature Response for T
HIGH
Overtemperature Events