ds1720 Maxim Integrated Products, Inc., ds1720 Datasheet - Page 6

• Manufacturer Part Number: ds1720
• Description: Ds1720 Econ-digital Thermometer And Thermostat
• Manufacturer: Maxim Integrated Products, Inc.

THERMOSTAT OUTPUT OPERATION Figure 3
OPERATION AND CONTROL
The DS1720 must have temperature settings resident in the T
A configuration/status register is also used to determine the method of operation that the DS1720 will use
in a particular application, as well as indicating the status of the temperature conversion operation. The
configuration register is defined as follows:
CONFIGURATION/STATUS REGISTER
where
DONE = Conversion Done bit. 1=conversion complete, 0=conversion in progress.
T
the value of T
device. This feature provides a method of determining if the DS1720 has ever been subjected to
temperatures above T
T
value of T
device. This feature provides a method of determining if the DS1720 has ever been subjected to
temperatures below T
NVB = Nonvolatile Memory Busy Flag. 1=write to an E
memory is not busy. A copy to E
CPU = CPU use bit. If CPU=0, the CLK/
If CPU is 1, the DS1720 will be used with a CPU communicating to it over the 3–wire port, and the
operation of the CLK/
nonvolatile E
1SHOT = One–Shot Mode. If 1SHOT is 1, the DS1720 will perform one temperature conversion upon
reception of the Start Convert T protocol. If 1SHOT is 0, the DS1720 will continuously perform
temperature conversion. This bit is stored in nonvolatile E
The DS1720 is shipped with 1SHOT=0.
DONE
HF
LF
= Temperature Low Flag. This bit will be set to 1 when the temperature is less than or equal to the
= Temperature High Flag. This bit will be set to 1 when the temperature is greater than or equal to
L
. It will remain 1 until reset by writing 0 into this location or by removing power from the
THF
2
H
memory, capable of at least 50,000 writes. The DS1720 is shipped with CPU=0.
. It will remain 1 until reset by writing 0 into this location or by removing power from the
H
L
CONV
while power has been applied.
while power has been applied.
TLF
pin is as a normal clock in concert with DQ and
2
NVB
may take up to 10 ms.
CONV
1
pin acts as a conversion start control, when
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0
2
H
2
memory, capable of at least 50,000 writes.
and T
memory cell in progress. 0=nonvolatile
CPU
L
registers for thermostatic operation.
1SHOT
RST
. This bit is stored in
RST
DS1720
is low.