DS1620

THERMOSTAT OUTPUT OPERATION Figure 3

OPERATION AND CONTROL

The DS1620 must have temperature settings resident in the TH and TL registers for thermostatic

operation. A configuration/status register also determines the method of operation that the DS1620 will

use in a particular application and indicates 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. The power-up/POR

state is a 1.

THF

= Temperature High Flag. This bit will be set to 1 when the temperature is greater than or equal

to the value of TH. It will remain 1 until reset by writing 0 into this location or by removing power from

the device. This feature provides a method of determining if the DS1620 has ever been subjected to

temperatures above TH while power has been applied. The power-up/POR state is a 0.

TLF

= Temperature Low Flag. This bit will be set to 1 when the temperature is less than or equal to

the value of TL. It will remain 1 until reset by writing 0 into this location or by removing power from the

device. This feature provides a method of determining if the DS1620 has ever been subjected to

temperatures below TL while power has been applied. The power-up/POR state is a 0.

NVB

CPU

low. If CPU is 1, the DS1620 will be used with a CPU communicating to it over the 3–wire port, and the

TL

TH

T(°C)

DONE

THF

TLF

NVB

1

0

CPU

1SHOT

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