Datasheet

Two-wire Digital Temperature Sensor
13
8585B–SEEPR–8/10
6.3. Configuration Register (16-bit Read/Write, Address = 01h)
The Atmel
®
AT30TS00 contains a 16-bit configuration register allowing the user to set key operational features of
the temperature sensor. The configuration register functions are described in Table 6-5 and Table 6-6.
Table 6-5. Configuration Register Bit Distribution
Bit 15 14 13 12 11 10 9 8
Symbol RFU HYSTENB SHTDWN
Default Value 0 0 0 0 0 0 0 0
R / W access R R R R R R/W R/W R/W
Bit 7 6 5 4 3 2 1 0
Symbol CRTALML WINLOCK EVTCLR EVTSTS EVTOUT CRITEVT EVTPOL EVTMOD
Default Value 0 0 0 0 0 0 0 0
R / W access R/W R/W W R R/W R/W R R/W
Table 6-6. Configuration Register Bit Description
Bit Symbol Description
15:11 RFU Reserved for Future Use and must be '0'
10:9 HYSTENB Hysteresis Enable
’00’ = 0°C Disable hysteresis (default power-on condition)
'01' = 1.5°C Enable hysteresis
‘10’ = 3.0°C Enable hysteresis
‘11’ = 6.0°C Enable hysteresis
The purpose of these bits is to control the hysteresis applied to the alarm trip point boundaries.
The above hysteresis applies to all limits when temperature drops below the user specified alarm
trip points. Please note that hysteresis applies to decreasing temperature only. Once ambient
temperature
is above a given threshold, it must drop below the boundary limit minus hysteresis in
order for a comparator
EVENT
to be cleared.
For example: If these bits are set to ‘01’ for 1.5°C and the Upper Alarm Trip limit is set to
85°C, as temperature rises above 85°C, bit 14 of temperature register will be set
to a ‘1’. Bit 14 will remain set until the ambient temperature drops below the
threshold (85°C) minus the hysteresis value or 83.5°C.
Note: Hysteresis is also applied to the
EVENT
pin functionality. When either of the
Crit_Alarm Trip or Alarm Window lock bits is set, this bit cannot be altered until
unlocked
8 SHTDWN Shutdown Mode
0 = Temperature sensor enabled for continuous conversion (power-on default)
1 = Temperature sensor disabled
In Shutdown mode, the temperature sensor is not active and will not generate interrupts or
update temperature data. The
EVENT
pin is deasserted (not driven).
When either of the Crit_Alarm Trip or Alarm Window lock bits is set, this bit cannot be altered
until unlocked.