604-00002 Parallax Inc, 604-00002 Datasheet

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... DESCRIPTION The DS1620 Digital Thermometer and Thermostat provides 9–bit temperature readings which indicate the temperature of the device. With three thermal alarm outputs, the DS1620 can also act as a thermostat driven high if the DS1620’s temperature is greater than or equal to a user–defined temperature HIGH TH ...

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... User–defined temperature settings are stored in nonvolatile memory, so parts can be programmed prior to insertion in a system, as well as used in standalone applications without a CPU. Temperature settings and temperature readings are all communicated to/from the DS1620 over a simple 3–wire interface. ORDERING INFORMATION PART PACKAGE MARKING ...

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... DS1620 as either a 9–bit word (taking words, with the most significant 7 bits being ignored or set illustrated in Table 3. After the MSB, the DS1620 will output 0s. Note that temperature is represented in the DS1620 in terms of a ½°C LSB, yielding the 9–bit format shown in Figure 2. TEMPERATURE, TH, and TL REGISTER FORMAT Figure 2 ...

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... OPERATION–THERMOSTAT CONTROLS Three thermally triggered outputs thermostat, as shown in Figure 3. When the DS1620’s temperature meets or exceeds the value stored in the high temperature trip register, the output T DS1620’s measured temperature becomes less than the stored value in the high temperature register, TH. ...

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... TH while power has been applied. The power-up/POR state 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 ...

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... The next nine clock cycles will output the contents of this register. Write TH [01h] This command writes to the TH (HIGH TEMPERATURE) register. After issuing this command the next nine clock cycles clock in the 9–bit temperature limit which will set the threshold for operation of the T output. ...

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... T output. LOW Read TH [A1h] This command reads the value of the TH (HIGH TEMPERATURE) register. After issuing this command the next nine clock cycles clock out the 9–bit temperature limit which sets the threshold for operation of the T output. HIGH Read TL [A2h] This command reads the value of the TL (LOW TEMPERATURE) register. After issuing this command the next nine clock cycles clock out the 9– ...

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... In continuous conversion mode, a Stop Convert T command will halt continuous conversion. To restart, the Start Convert T command must be issued. In one–shot mode, a Start Convert T command must be issued for every temperature reading desired Writing to the E requires room temperature. After issuing a write command no further writes should be requested for at least 10 ms. PROTOCOL THERMOSTAT COMMANDS ...

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FUNCTION EXAMPLE Example: CPU sets up DS1620 for continuous conversion and thermostatic function. DS1620 MODE CPU MODE (3-WIRE ...

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... Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. ...

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... Standby Supply Current Input Current on Each Pin Thermal Drift SINGLE CONVERT TIMING DIAGRAM (STAND-ALONE MODE) CONV AC ELECTRICAL CHARACTERISTICS PARAMETERS Temperature Conversion Time Data to CLK Setup CLK to Data Hold CLK to Data Delay CLK Low Time CLK High Time CLK Frequency CLK Rise and Fall ...

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... All voltages are referenced to ground. 2. Valid for design revisions D1 and above. The supply range for Rev. C2 and below is 4.5V < 5.5V. 3. Thermometer error reflects temperature accuracy as tested during calibration. 4. Logic 0 voltages are specified at a sink current Logic 1 voltages are specified at a source current of 1 mA. ...