DS1921Z-F5# Maxim Integrated Products, DS1921Z-F5# Datasheet
DS1921Z-F5#
Specifications of DS1921Z-F5#
Related parts for DS1921Z-F5#
DS1921Z-F5# Summary of contents
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... Probe Pin Configuration appears at end of data sheet. Thermochron, iButton, and 1-Wire are registered trademarks of Maxim Integrated Products, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Thermochron iButton ♦ ...
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Thermochron iButton ABSOLUTE MAXIMUM RATINGS IO Voltage Range Relative to GND ..........................-0.5V to +6V IO Sink Current....................................................................20mA * Storage or operation above +50°C significantly reduces battery life. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to ...
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ELECTRICAL CHARACTERISTICS (continued +2.8V to +5.25V -40°C to +85°C.) PUP A PARAMETER SYMBOL IO PIN: 1-Wire WRITE Write-Zero Low Time (Notes 1, 12) Write-One Low Time (Notes 1, 13) IO PIN: 1-Wire READ Read Low Time ...
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Thermochron iButton ELECTRICAL CHARACTERISTICS (continued +2.8V to +5.25V -40°C to +85°C.) PUP A Note 17: WARNING: Not for use as the sole method of measuring or tracking temperature in products and articles that could affect the ...
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Minimum Product Lifetime vs. Temperature at Different Sample Rates 11.00 10.00 9.00 8.00 7.00 6.00 5.00 4.00 EVERY MINUTE 3.00 NO SAMPLES 2.00 EVERY 3 MINUTES OSCILLATOR OFF 1.00 ...
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Thermochron iButton Minimum Product Lifetime vs. Sample Rate at Different Temperatures 11.00 10.00 9.00 8.00 7.00 6.00 5.00 4.00 3.00 2.00 1.00 0.00 1 2.0 1.5 1.0 0.5 0 -0.5 -1.0 -1.5 -2.0 -40 -30 6 _______________________________________________________________________________________ 10 MINUTES BETWEEN ...
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Detailed Description The DS1921G Thermochron iButton is an ideal device to monitor the temperature of any object it is attached to or shipped with, such as perishable goods or con- tainers of temperature-sensitive chemicals. The read/write NV memory can store ...
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Thermochron iButton histogram memory; and 2048 bytes of data-logging memory. Except for the ROM and the scratchpad, all other memory is arranged in a single linear address space. All memory reserved for logging purposes, including counter registers and several other ...
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MSB 8-BIT CRC CODE MSB LSB MSB Figure 3. 64-Bit Lasered ROM 1ST 2ND 3RD STAGE STAGE STAGE Figure 4. 1-Wire CRC Generator using a polynomial generator consisting of a shift regis- ter and ...
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Thermochron iButton 32-BYTE INTERMEDIATE STORAGE SCRATCHPAD ADDRESS 0000h to 01FFh 0200h to 021Fh 0220h to 027Fh 0280h to 07FFh 0800h to 087Fh 0880h to 0FFFh 1000h to 17FFh 1800h to 1FFFh Figure 5. Memory Map ADDRESS BIT 7 BIT 6 ...
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ADDRESS BIT 7 BIT 6 BIT 5 0210h 0211h Temperature Read-Out (Forced Conversion) 0212h 0213h TCB 0214h MEMCLR 0215h 0216h 0217h 0218h 0219h 021Ah 021Bh 021Ch 021Dh 021Eh 021Fh * The left entry in the ACCESS column is valid between ...
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Thermochron iButton ADDRESS BIT 7 BIT 6 0200h 0 0201h 0 0202h 0 12/24 0203h 0 0 0204h 0 0 0205h CENT 0 0206h 0207h MS 0208h MM 0209h MH 12/24 020Ah MD 0 ALARM REGISTER MASK BITS (BIT 7 ...
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ADDRESS BIT 7 BIT 6 020Bh 020Ch ADDRRESS BIT 7 BIT 6 020Dh Temperature Conversion The DS1921G measures temperatures with a resolution of 0.5°C. Temperature values are represented in a sin- gle byte as an unsigned binary number, which trans- ...
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Thermochron iButton ADDRESS BIT 7 BIT 6 EOSC 020Eh EMCLR The DS1921G is set up for its operation by writing appropriate data to its special function registers that are located in the register page. Several functions that are controlled by ...
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ADDRESS BIT 7 BIT 6 TCB 0214h MEMCLR The Status register holds device status information and alarm flags. The register is located at address 0214h. Writing to this register does not necessarily end a mission. The functional assignments of the ...
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Thermochron iButton ADDRESS BIT 7 BIT 6 0215h 0 0216h 0 12/24 0217h 0 0 0218h 0 0 0219h ADDRESS BIT 7 BIT 6 021Ah 021Bh 021Ch ADDRESS BIT 7 BIT 6 021Dh 021Eh 021Fh Mission Timestamp The Mission Timestamp ...
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TEMPERATURE READING 00h 01h 02h 03h 04h 05h 06h 07h 08h … F3h F4h F5h F6h F7h F8h F9h FAh Figure 7. Histogram Bin and Temperature Cross-Reference For the temperature histogram, the DS1921G provides 63 bins that begin at memory ...
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Thermochron iButton ADDRESS 0220h 0221h 0222h 0223h 0224h to 0227h 0228h to 024Fh 0250h 0251h 0252h 0253h 0254h to 0257h 0258h to 027Fh Figure 8. Alarm Timestamps and Durations Address Map 214h). This way, if the search conditions (address 20Eh) ...
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Next, the low temperature and high temperature thresh- olds that specify the temperature tolerance band must be defined. The Temperature Conversion section describes how to convert a temperature value into the binary code to be written to the threshold registers. ...
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Thermochron iButton BIT NUMBER TARGET ADDRESS (TA1) TARGET ADDRESS (TA2) ENDING ADDRESS WITH DATA STATUS (E/S) (READ-ONLY) Figure 9. Address Registers write command was not recognized by the device. If everything went correctly, both flags are cleared and the ending ...
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Read Scratchpad [AAh] This command is used to verify scratchpad data and target addresses. After issuing the Read Scratchpad command, the master begins reading. The first 2 bytes are the target address. The next byte is the ending off- set/data ...
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Thermochron iButton MASTER Tx MEMORY OR FROM ROM FUNCTIONS CONTROL FUNCTION COMMAND FLOWCHART (FIGURE 13) 0Fh N WRITE SCRATCHPAD? Y DS1921G SETS EMCLR = 0 MASTER Tx TA1 [T7:T0], TA2 [T15:T8] DS1921G SETS SCRATCHPAD OFFSET = [T4:T0] AND CLEARS (PF, ...
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FROM FIGURE 10a F0h N READ MEMORY? Y DS1921G SETS EMCLR = 0 MASTER Rx TA1 [T7:T0], TA2 [T15:T8] DS1921G SETS MEMORY ADDRESS = [T15:T0] DS1921G MASTER Rx DATA BYTE FROM INCREMENTS MEMORY ADDRESS ADDRESS COUNTER Y MASTER Tx RESET? ...
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Thermochron iButton FROM FIGURE 10b TO FIGURE 10b Figure 10c. Memory/Control Function Flowchart 24 ______________________________________________________________________________________ 44h CONVERT N TEMPERATURE? Y TEMPERATURE DS1921G SETS CONVERSION PROCESS EMCLR = 0 DS1921G SETS Y MISSION IN TCB = 0 PROGRESS? N DS1921G PERFORMS ...
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Read Memory with CRC [A5h] The Read Memory with CRC command is used to read memory data that cannot be packetized, such as the register page and the data recorded by the device dur- ing a mission. The command works ...
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Thermochron iButton MISSION START PROCESS Y MIP = MEMCLR = NEW SAMPLE RATE = 0? N DS1921G COPIES NEW SAMPLE RATE FROM SCRATCHPAD TO SAMPLE RATE REGISTER DS1921G SETS ...
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Since all mission samples occur on the sec- onds rollover (59 to 00), memory conflicts can be avoid first reading the RTC seconds counter. For example takes 2s to read the data log, then avoid ...
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Thermochron iButton All transactions on the 1-Wire bus begin with an initial- ization sequence. The initialization sequence consists of a reset pulse transmitted by the bus master, followed by presence pulse(s) transmitted by the slave(s). The presence pulse lets the ...
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FROM MEMORY/CONTROL FUNCTIONS FLOWCHART (FIGURE 10) MASTER Tx ROM FUNCTION COMMAND 33h READ ROM COMMAND? Y DS1921G Tx FAMILY CODE (1 BYTE) DS1921G Tx SERIAL NUMBER (6 BYTES) DS1921G Tx CRC BYTE *TO BE TRANSMITTED OR RECEIVED AT OVERDRIVE SPEED ...
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Thermochron iButton TO FIGURE 13a FROM FIGURE 13a FROM FIGURE 13a TO FIGURE 13a ***ALWAYS TO BE TRANSMITTED AT OVERDRIVE SPEED. Figure 13b. ROM Functions Flowchart 30 ______________________________________________________________________________________ CCh 3Ch N N SKIP ROM OVERDRIVE- COMMAND? SKIP ROM ...
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Overdrive-Skip ROM [3Ch single-drop bus this command can save time by allowing the bus master to access the memory/control functions without providing the 64-bit ROM code. Unlike the normal Skip ROM command, the Overdrive-Skip ROM command sets the ...
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Thermochron iButton A t duration of 480µs or longer exits the overdrive RSTL mode, returning the device to standard speed. If the DS1921G is in overdrive mode and t than 80µs, the device remains in overdrive mode. After the bus ...
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WRITE-ONE TIME SLOT t W1L V PUP V IHMASTER ILMAX RESISTOR WRITE-ZERO TIME SLOT V PUP V IHMASTER ILMAX RESISTOR READ-DATA TIME SLOT t ...
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Thermochron iButton With the Read Scratchpad command, the CRC is gen- erated by first clearing the CRC generator and then shifting in the command code, the target addresses TA1 and TA2, the E/S byte, and the scratchpad data starting at ...
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Command-Specific 1-Wire Communication Protocol—Legend SYMBOL <00 to EOP> Transfer of as many 00h bytes as are needed to reach a memory page boundary <32 bytes> Transfer of 32 bytes <data> Transfer of an undetermined amount of data CRC-16 Transfer of ...
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Thermochron iButton Read Memory with CRC (Success) RST PD Select RMC TA <data to EOP> CRC-16 The “32 bytes” are either valid page data or 00h bytes when reading reserved pages 20 through through 127 or pages ...
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Step 1: Set the RTC Let the actual time be 15:30:00 hours on Monday, the 1st of April in 2002. This results in the following data to be writ- ten to the RTC registers: ADDRESS 200h DATA 00h With only ...
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Thermochron iButton Step 2: Clear the data of the previous mission Set the EMCLR bit to 1, enable the RTC, and then execute the Clear Memory command. The RTC oscillator must be stable before the Clear Memory command is issued. ...
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Step 3: Set the search condition and Mission Start Delay and clear the alarm flags In this example, the rollover is disabled and the search condition is set for a high temperature only. The mission is to start with a ...
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Thermochron iButton Step 4: Set the temperature alarms and write the Sample Rate to start the mission In this example, the temperature alarms are set to -5°C for the low temperature threshold and 0°C for the high tem- perature threshold. ...
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Pin Configuration 5.89mm 0.51mm BRANDING 89 21 ® 000000FBC52B ® 1-Wire ® Thermochrom IO GND ______________________________________________________________________________________ Thermochron iButton For the latest package outline information and land patterns www.maxim-ic.com/packages. PACKAGE TYPE F5 iButton 16.25mm 17.35mm Package Information PACKAGE CODE ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 42 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products ...