DS1629S/T&R Maxim Integrated Products, DS1629S/T&R Datasheet
DS1629S/T&R
Specifications of DS1629S/T&R
Related parts for DS1629S/T&R
DS1629S/T&R Summary of contents
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FEATURES § Measures temperatures from -55°C to +125°C; Fahrenheit equivalent is -67°F to 257°F § Real time clock counts seconds, minutes, hours, date of the month, month, day of the week, and year with leap year compensation through the ...
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The open-drain alarm output of the DS1629 will become active when either the measured temperature exceeds the programmed over-temperature limit (T setting. The user can configure which event (time only, temperature only, either, or neither) will generate an alarm condition. ...
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As conversions are performed in the background, reading the temperature register does not affect the conversion in progress. The host can modify DS1629 configuration such that it does not power up in the auto-convert or continuous convert modes. This ...
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DS1629 FUNCTIONAL BLOCK DIAGRAM Figure 1 OPERATION-Measuring Temperature The DS1629 measures temperature through the use of an on-chip temperature measurement technique with an operating range from -55°C to +125°C. The device can be configured to perform a single conversion, store ...
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At the same time, the counter is then preset with a value determined by the slope accumulator circuitry. This circuitry is needed to compensate for the parabolic behavior of the oscillators over temperature. The counter is then clocked again until ...
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OPERATION-Real Time Clock/Calendar DS1629 real-time clock/calendar data is accessed with the 2-wire command protocol C0h. If the R/ in the 2-wire control byte is set to 0, the bus master will set the clock (write to the clock register). The ...
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OPERATION-Alarms The DS1629 features an open-drain alarm output with a user-definable active state (factory default is active low). By programming the configuration register, the user also defines the event, if any, would generate an alarm condition. The four possibilities are: ...
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Thermometer Alarm The thermostat comparator updates as soon as a temperature conversion is complete. When the DS1629’s temperature meets or exceeds the value stored in the high temperature trip register (TH), the TAF flag becomes active (high), and will stay ...
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DS1629 SRAM FORMAT Table 4 BYTE 00h 01h 02h • • • 1Eh 1Fh DS1629 CLOCK ALARM REGISTER FORMAT Figure 4 OPERATION-Configuration/Status Register The configuration/status register is accessed via the Access Config (ACh) function command. Writing to or reading from ...
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DS1629 Thermometer Power-up Modes Table 5 CNV ISH 0 0 Powers up converting continuously (factory default Automatically performs one conversion upon power-up. Subsequent conversions require a Start Convert command Powers up in standby; upon Start Convert ...
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CAL = Clock Alarm Latch. This volatile status bit will be set to "1" when the clock comparator becomes active. Once set, it will remain latched until DS1629 power is cycled. A "0" in this location indicates the clock has ...
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Acknowledge: Each receiving device, when addressed, is obliged to generate an acknowledge after the reception of each byte. The master device must generate an extra clock pulse which is associated with this acknowledge bit. A device that acknowledges must pull ...
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SERIAL COMMUNICATION WITH DS1629 Figure ...
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SERIAL COMMUNICATION WITH DS1629 Figure 6 (continued ...
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COMMAND SET The command set for the DS1629 as shown in Table follows: Access Config [ACh "0", this command writes to the configuration register. After issuing this command, the next W data byte value ...
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Access TH [A1h "0", this command writes to the TH register. After issuing this command, the next two bytes W written to the DS1629, in the format described for thermostat set-points, will set the high temperature threshold ...
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NOTES: 1. Data direction depends upon R/ 2. When accessing (reading from or writing to) addressed SRAM in the page mode, the address pointer will automatically roll from the most significant byte to the least significant byte following the ACK ...
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Sample Command Sequence Table 9 Example: The bus master configures the DS1629 in the power-up one-shot mode. It sets the ALRM output active low with only the thermometer generating an ALRM and disables the oscillator output. It then sets the ...
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Sample Command Sequence Table 10 Example: Assuming the DS1629 is configured such that the clock is running and the thermometer is converting, read the current time and temperature. Also read the status of the alarm flags. BUS MASTER DS1629 MODE ...
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ABSOLUTE MAXIMUM RATINGS* Voltage Relative to Ground (Note 1) DD Voltage on any other pin, Relative to Ground Operating Temperature Storage Temperature Soldering Temperature This is a stress rating only and functional operation of the device at ...
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DC ELECTRICAL CHARACTERISTICS: DIGITAL THERMOMETER PARAMETER SYMBOL DS1629 Thermometer Error Resolution Conversion Time t CONVT AC ELECTRICAL CHARACTERISTICS: 2-WIRE INTERFACE PARAMETER SYMBOL SCL Clock Period Data In Setup Time to SCL High Data Out Stable after SCL Low SDA Low ...
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Cb - total capacitance of one bus line in pF. 9. Refer to Application Note 58. 2-WIRE BUS TIMING DIAGRAM Figure 7 Typical DS1629 Thermometer Performance Curve Figure ...