DS1922L-F5# Maxim Integrated Products, DS1922L-F5# Datasheet
DS1922L-F5#
Specifications of DS1922L-F5#
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DS1922L-F5# Summary of contents
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... First Applies Voltage ♦ Meets UL 913 (4th Edit.); Intrinsically Safe Apparatus: Features Approved Under Entity Concept for Use in Class I, Division 1, Group and D Locations PART DS1922L-F5# DS1922T-F5# # Denotes a RoHS-compliant device that may include lead(Pb) that is exempt under the RoHS requirements. PART DS9096P ...
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... IO Voltage Range to GND ........................................-0.3V to +6V IO Sink Current....................................................................20mA Operating Temperature Range DS1922L ...........................................................-40°C to +85°C DS1922T ............................................................0°C to +125°C * Storage or operation above +50°C significantly reduces battery life. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied ...
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Temperature Logger iButton with 8KB ELECTRICAL CHARACTERISTICS (continued +3.0V to +5.25V.) PUP PARAMETER SYMBOL Presence-Detect Low Time Presence-Detect Sample Time (Note 2) IO PIN: 1-Wire WRITE Write-Zero Low Time (Note 2) Write-One Low Time (Notes 2, 14) IO ...
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... OVERDRIVE SPEED (μs) MAX MIN MAX 7 (undefined 240 8 24 120 detected as logic 0. HY has been previously reached the input-high IL DS1922L/DS1922T VALUES STANDARD SPEED OVERDRIVE SPEED (μs) (μs) MIN MAX MIN * 65 (undefined) 9.5 (undefined) 690 720 287 7 60 120 7.5 MAX 80 ...
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... Temperature Logger iButton with 8KB DS1922L Minimum Product Lifetime vs. Temperature, Slow Sampling EVERY MINUTE NO SAMPLES -40 -30 -20 -10 EVERY MINUTE NO SAMPLES -40 -30 -20 -10 _______________________________________________________________________________________ Data-Log Memory EVERY 3 MINUTES EVERY 10 MINUTES EVERY 60 MINUTES OSCILLATOR OFF TEMPERATURE (°C) EVERY 10 MINUTES EVERY 3 MINUTES OSCILLATOR OFF ...
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... Temperature Logger iButton with 8KB Data-Log Memory DS1922L Minimum Product Lifetime vs. Temperature, Fast Sampling EVERY SECOND EVERY 30 SECONDS 350 300 250 200 150 100 50 0 -40 -30 EVERY SECOND EVERY 30 SECONDS 100 -40 -30 6 _______________________________________________________________________________________ EVERY 3 SECONDS EVERY 60 SECONDS -20 - TEMPERATURE (°C) EVERY 3 SECONDS ...
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Temperature Logger iButton with 8KB DS1922T Minimum Product Lifetime vs. Temperature, Slow Sampling EVERY MINUTE EVERY 60 MINUTES EVERY MINUTE EVERY 60 MINUTES 10 9 ...
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Temperature Logger iButton with 8KB Data-Log Memory DS1922T Minimum Product Lifetime vs. Temperature, Fast Sampling EVERY SECOND EVERY 30 SECONDS 350 300 250 200 150 100 EVERY SECOND EVERY 30 SECONDS 100 ...
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... Temperature Logger iButton with 8KB DS1922L Minimum Product Lifetime vs. Sample Rate 10 1 0.1 0.01 0.01 0 0.1 0.01 0.001 0.01 0.1 _______________________________________________________________________________________ Data-Log Memory 1 10 MINUTES BETWEEN SAMPLES 1 10 MINUTES BETWEEN SAMPLES 0°C +40°C -40°C +60°C +75°C +85°C 100 0°C +40°C -40°C +60° ...
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Temperature Logger iButton with 8KB Data-Log Memory DS1922T Minimum Product Lifetime vs. Sample Rate 10 1 0.1 0.01 0. 0.1 0.01 0.001 0.01 10 ______________________________________________________________________________________ 0.1 1 MINUTES BETWEEN SAMPLES 0.1 1 MINUTES BETWEEN SAMPLES 0°C +40°C +60°C ...
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... UNCORRECTED MAXIMUM ERROR 0.5 SW CORRECTED MAXIMUM ERROR 0.0 SW CORRECTED MINIMUM ERROR -0.5 UNCORRECTED MINIMUM ERROR -1.0 -1.5 -2.0 -2 NOTE: THE GRAPHS ARE BASED ON 11-BIT DATA. ______________________________________________________________________________________ Data-Log Memory DS1922L Temperature Accuracy TEMPERATURE (°C) DS1922T Temperature Accuracy 100 110 TEMPERATURE (°C) 80 120 ...
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... Temperature Logger iButton with 8KB Data-Log Memory 2.0 1.0 0.0 -1.0 -2.0 -3.0 -4.0 -5.0 -40 -30 2.0 0.0 -2.0 -4.0 -6.0 -8.0 -10.0 -12 ______________________________________________________________________________________ DS1922L RTC Accuracy (Typical) -20 - TEMPERATURE (°C) DS1922T RTC Accuracy (Typical TEMPERATURE (° 100 110 120 ...
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... Temperature Logger iButton with 8KB Detailed Description The DS1922L is an ideal device to monitor for extended periods of time the temperature of any object it is attached to or shipped with, such as fresh produce, medical drugs and supplies, and for use in refrigerators and freezers. With its shifted temperature range, the ...
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... OSCILLATOR THERMAL SENSE Figure 1. Block Diagram 14 ______________________________________________________________________________________ ROM 64-BIT IO FUNCTION LASERED CONTROL ROM MEMORY FUNCTION CONTROL DS1922L DS1922T GENERAL-PURPOSE SRAM (512 BYTES) INTERNAL TIMEKEEPING, REGISTER PAGES CONTROL REGISTERS, (64 BYTES) AND COUNTERS CALIBRATION MEMORY ADC (64 BYTES) CONTROL DATA-LOG MEMORY LOGIC 8KB ...
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... STAGE STAGE Figure 4. 1-Wire CRC Generator ______________________________________________________________________________________ OTHER DEVICES DS1922L/DS1922T AVAILABLE COMMANDS: DATA FIELD AFFECTED: READ ROM 64-BIT ROM, RC-FLAG MATCH ROM 64-BIT ROM, RC-FLAG SEARCH ROM 64-BIT ROM, RC-FLAG CONDITIONAL SEARCH ROM 64-BIT ROM, RC-FLAG, ALARM FLAGS, SEARCH CONDITIONS SKIP ROM ...
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... Temperature Logger iButton with 8KB Data-Log Memory Figure 5 shows the DS1922L/DS1922T memory map. Pages contain 512 bytes of general-purpose SRAM. The various registers to set up and control the device fill pages 16 and 17, called register pages 1 and 2 (see Figure 6 for details). Pages 18 and 19 pro- vide storage space for calibration data ...
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... Years 0206h 0207h 0 0 0208h 0209h 020Ah (No Function with the DS1922L/DS1922T) 020Bh (No Function with the DS1922L/DS1922T) 020Ch Low Byte 020Dh 020Eh (No Function with the DS1922L/DS1922T) 020Fh (No Function with the DS1922L/DS1922T) 0210h 0 0 0211h 1 1 0212h 0 0 0213h 1 1 0214h BOR 1 0215h ...
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Temperature Logger iButton with 8KB Data-Log Memory ADDRESS BIT 7 BIT 6 0219h 0 10 Seconds 021Ah 0 10 Minutes 20 Hour 021Bh 0 12/24 AM/PM 021Ch 0 0 021Dh CENT 0 021Eh 10 Years 021Fh 0220h 0221h 0222h 0223h ...
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... These bits always read 0 regardless of how they are written. The number representation of the RTC registers is binary-coded decimal (BCD) format. The DS1922L/DS1922T’s RTC can run in either 12hr or 24hr mode. Bit 6 of the Hours register (address 0202h) is defined as the 12hr- or 24hr-mode select bit. When high, the 12hr mode is selected ...
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... DS1922T, use “-1” instead of “-41.” To specify the temperature alarm thresholds, the previ- ous equations are resolved to: The “+82” applies to the DS1922L. For the DS1922T, use “+2.” Because the temperature alarm threshold is only one byte, the resolution or temperature increment is limit 0.5° ...
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... BIT 4 BIT minimize the power consumption of the DS1922L/ DS1922T, the RTC oscillator should be turned off when these devices are not in use. The oscillator on/off bit is located in the RTC Control register. This register also includes the EHSS bit, which determines whether the sample rate is specified in seconds or minutes ...
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... Note: During a mission, there is only read access to this register. Bits 6 and 7 have no function. They always read 1 and cannot be written to 0. Bits 1 and 3 control functions that are not available with the DS1922L/DS1922T. Bit 1 must be set to 0. Under this condi- tion the setting of bit 3 becomes a “don’t care.” ...
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... Note: There is only read access to this register. Bits have no function. They always read 1. Bits 2 and 3 have no function with the DS1922L/DS1922T. They always read 0. The alarm status bits are cleared simultaneously when the Clear Memory Function is invoked. See the Memory and Control Function Commands section for details. ...
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... For a typical mission, the Mission Start Delay mission is too long for a single DS1922L/DS1922T to store all readings at the selected sample rate, one can use several devices and set the Mission Start Delay for the second device to start recording as soon as the memory of the first device is full, and so on ...
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... BIT 5 BIT 4 EPW Other Indicators The DS1922L/DS1922T are designed to use two pass- words that control read access and full access. Reading from or writing to the scratchpad as well as the Forced Conversion command does not require a pass- word. The password must be transmitted immediately after the command code of the memory or control func- tion ...
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... FP0, FP1…FP62, FP63. It affects the functions Read Memory with CRC, Copy Scratchpad, Clear Memory, Start Mission, and Stop Mission. The DS1922L/DS1922T execute the command only if the password transmitted by the master was correct or if password checking is not enabled. Due to the special behavior of the write-access logic, the Password Control register and both passwords must be written at the same time ...
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... EHSS = 1). If there is a risk of unauthorized access to the DS1922L/ DS1922T or manipulation of data, one should define passwords for read access and full access. Before the passwords become effective, their use must be enabled ...
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... Sample Rate register and the EHSS bit. If the start upon temperature alarm mode is chosen (SUTA = 1) and temperature logging is enabled (ETL = 1), the DS1922L/DS1922T first wait until the start delay is over. Then the device wakes up in intervals as speci- fied by the sample rate and EHSS bit and measures the temperature ...
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... Figure 9 shows the protocols necessary for accessing the memory and the special function registers of the DS1922L/DS1922T. An example on how to use these and other functions to set up the DS1922L/DS1922T for a mission is included in the Mission Example: Prepare and Start a New Mission section. The communication between the master and the DS1922L/DS1922T takes place either at standard speed (default overdrive speed ( ...
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... CRC generator and then shifting in the contents of the data memory page. After the 16-bit CRC of the last page is read, the bus master receives logic 1s from the DS1922L/DS1922T until a reset pulse is issued. The Read Memory with CRC command sequence can be ended at any point by issuing a reset pulse ...
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Temperature Logger iButton with 8KB MASTER Tx MEMORY OR FROM ROM FUNCTIONS CONTROL FUNCTION COMMAND FLOWCHART (FIGURE 11) 0Fh N WRITE SCRATCHPAD? Y MASTER Tx TA1 [T7:T0] MASTER Tx TA2 [T15:T8] DS1922 SETS SCRATCHPAD OFFSET = [T4:T0] AND CLEARS (PF, ...
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Temperature Logger iButton with 8KB Data-Log Memory 69h FROM FIGURE 9a READ MEMORY [WITH PW] AND CRC Y MASTER Tx TA1 [T7:T0], TA2 [T15:T8] MASTER Tx DECISION MADE 64 BITS [PASSWORD] BY DS1922 PASSWORD ACCEPTED? Y DECISION MADE BY MASTER ...
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Temperature Logger iButton with 8KB FROM FIGURE 9b START MISSION 64 BITS [PASSWORD] FFh DUMMY BYTE N PASSWORD ACCEPTED? Y PROGRESS? N MEMCLR = 1? DS1922 SETS MEMCLR = 0 DS1922 INITIATES MISSION START DELAY PROCESS N MASTER Tx RESET? ...
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... General Status register reads 1. During a mission there is only read access to the register pages. Stop Mission with Password [33h] The DS1922L/DS1922T use a control function com- mand to stop a mission. Only a mission that is in progress can be stopped. After the command code, the master must transmit the 64-bit full-access pass- word followed by a FFh dummy byte ...
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Temperature Logger iButton with 8KB Memory Access Conflicts While a mission is in progress or while the device is waiting for a temperature alarm to start a mission, peri- odically a temperature sample is taken and logged. This “internal activity” ...
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... With the DS1922L/ DS1922T, the bus must be left low for no longer than 12µs at overdrive to ensure that no DS1922L/DS1922T on the 1-Wire bus performs a reset. The DS1922L/ DS1922T communicate properly when used in conjunc- tion with a DS2480B or DS2490 1-Wire driver and adapters that are based on these driver chips ...
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... The pres- ence pulse lets the bus master know that the DS1922L/DS1922T are on the bus and are ready to oper- ate. For more details, see the 1-Wire Signaling section. 1-Wire ROM Function Commands ...
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... AND result). The Overdrive-Match ROM command followed by a 64-bit ROM sequence transmitted at overdrive speed allows the bus master to address a specific DS1922L/ DS1922T on a multidrop bus and to simultaneously set it in overdrive mode. Only the DS1922L/DS1922T that exactly matches the 64-bit ROM sequence respond to the subsequent memory/control function command ...
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Temperature Logger iButton with 8KB FROM MEMORY/CONTROL FUNCTION FLOWCHART (FIGURE 9) BUS MASTER Tx ROM FUNCTION COMMAND 33h N READ ROM COMMAND DS1922 Tx FAMILY CODE (1 BYTE) DS1922 Tx SERIAL NUMBER (6 BYTES) DS1922 Tx ...
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Temperature Logger iButton with 8KB Data-Log Memory TO FIGURE 11a CCh FROM FIGURE 11a SKIP ROM COMMAND FROM FIGURE 11a TO FIGURE 11a NOTE: THE OD FLAG REMAINS THE DEVICE WAS ALREADY AT ...
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... ROM and memory function com- mand. If the bus master uses slew-rate control on the falling edge, it must pull down the line for t compensate for the edge RSTL longer exits the overdrive mode, returning the device to standard speed. If the DS1922L/DS1922T are in over- MASTER Tx "RESET PULSE" V PUP V IHMASTER ...
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... DS1922T start pulling the data line low; their internal timing generator determines when this pulldown ends and the voltage starts rising again. When responding with a 1, the DS1922L/DS1922T do not hold the data line low at all, and the voltage starts rising as soon over ...
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... TL V ILMAX RESISTOR WRITE-ZERO TIME SLOT V PUP V IHMASTER ILMAX RESISTOR READ-DATA TIME SLOT PUP V IHMASTER ILMAX RESISTOR Figure 13. Read/Write Timing Diagrams ______________________________________________________________________________________ ε t SLOT MASTER t W0L t SLOT MASTER MSR MASTER SAMPLING WINDOW δ t SLOT MASTER Data-Log Memory ε t REC t REC DS1922L/DS1922T 43 ...
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... X Figure 15. CRC-16 Hardware Description and Polynomial CRC Generation The DS1922L/DS1922T use two types of CRCs. One CRC is an 8-bit type and is stored in the most signifi- cant byte of the 64-bit ROM. The bus master can com- pute a CRC value from the first 56 bits of the 64-bit ...
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... Temperature Logger iButton with 8KB ing in the command code, the target addresses TA1 and TA2, and all the data bytes. The DS1922L/DS1922T transmit this CRC only if the data bytes written to the scratchpad include scratchpad ending offset 11111b. The data can start at any location within the scratchpad. ...
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Temperature Logger iButton with 8KB Data-Log Memory Command-Specific 1-Wire Communication Protocol—Color Codes Master-to-Slave Slave-to-Master Write Scratchpad, Reaching the End of the Scratchpad (Cannot Fail) RST PD Select WS TA <Data to EOS> Read Scratchpad (Cannot Fail) RST PD Select RS ...
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... To verify success, read the General Status register at address 0215h. If MIP is 0, the command was executed successfully. Mission Example: Prepare and Start a New Mission Assumption: The previous mission has been ended by using the Stop Mission command. Passwords are not enabled. The device is a DS1922L. Starting a mission requires three steps: MASTER MODE ...
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... Alarm Controls (Response to Conditional Search) • General Mission Parameters (e.g., Channels to Log and Logging Format, Rollover, Start Mode) • Mission Start Delay The following data sets up the DS1922L for a mission that logs temperature using 8-bit format. EXAMPLE VALUES Time Date ...
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Temperature Logger iButton with 8KB With only a single device connected to the bus master, the communication of step 2 looks like this: MASTER MODE ...
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... Read the 64-bit ROM to obtain the family code. If family code ≠ 41h, then stop (wrong device). Read the configuration byte at address 0226h. If code = 40h, then Tr1 = 60, Offset = 41 (DS1922L) If code = 60h, then Tr1 = 90, Offset = 1 (DS1922T) For all other codes, stop (wrong device). ...
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... T = 22.647°C CORR Note: The software correction requires floating-point arithmetic (24 bit or better). Suitable math libraries for microcontrollers are found on various websites and are included in cross com- pilers. Thermochron is a registered trademark of Maxim Integrated Products, Inc. ______________________________________________________________________________________ F5 SIZE 5.89mm CORRECTION IO READING For the latest package outline information and land patterns www ...
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... Added bullet “Water resistant or waterproof if placed inside DS9107 iButton capsule (Exceeds Water Resistant 3 ATM requirements)”. • Deleted “application pending” from UL bullet and safety statement. • Added text to Application section: Note that the initial sealing level of DS1922L/ 7 12/07 DS1922T achieves IP56. Aging and use conditions can degrade the integrity of ...