EVALUATION KIT AVAILABLE Thermochron iButton Device DS1921G General Description Benefits and Features The Thermochron iButton device (DS1921G) is a High Accuracy, Full-Featured Digital Temperature rugged, self-sufficient system that measures temperature Logger Simplifies Temperature Data Collection and and records the result in a protected memory section. Dissemination of Electronic Temperature Record The recording is done at a user-defined rate, both as a Accuracy 1C from -30C to +70C (See the direct storage of temperature values as well as in the Electrical Characteristics for Accuracy Specification) form of a histogram. Up to 2048 temperature values Digital Thermometer Measures Temperature in taken at equidistant intervals ranging from 1 to 255min 0.5C Increments can be stored. The histogram provides 63 data bins with Built-In Real-Time Clock (RTC) and Timer Has a resolution of 2.0C. If the temperature leaves a user- Accuracy of 2 Minutes per Month from 0C to +45C programmable range, the DS1921G also records when Automatically Wakes Up and Measures this happened, for how long the temperature stayed out- Temperature at User-Programmable Intervals from side the permitted range, and if the temperature was too 1 Minute to 255 Minutes high or too low. An additional 512 bytes of battery- Logs Consecutive Temperature Measurements in backed SRAM allow storing information pertaining to the 2kB of Datalog Memory object to which the DS1921G is associated. Data is Records a Long-Term Temperature Histogram with transferred serially through the 1-Wire protocol, which 2.0C Resolution requires only a single data lead and a ground return. Every DS1921G is factory lasered with a guaranteed Programmable Temperature High and Temperature unique, electrically readable, 64-bit registration number Low Alarm Trip Points that allows for absolute traceability. The durable stainless Records Up to 24 Timestamps and Durations steel package is highly resistant to environmental haz- When Temperature Leaves the Range Specified ards such as dirt, moisture, and shock. Accessories per- by the Trip Points mit the DS1921G to be mounted on almost any object Individually Calibrated in a NIST-Traceable Chamber including containers, pallets, and bags. Complies to Standard EN12830 512 Bytes of General-Purpose Battery-Backed SRAM Applications Rugged Construction Survives Harsh Environments Temperature Logging in Cold Chain, Food Safety, Water Resistant Enclosure (IP56) or Waterproof if Pharmaceutical, and Medical Products Placed Inside DS9107 iButton Capsule (Exceeds Water Resistant 3 ATM Requirements) Ordering Information CE, FCC, and UL913 Certifications PART TEMP RANGE PIN-PACKAGE Simple Serial Port Interfaces to Most Microcontrollers DS1921G-F5 -40C to +85C F5 Can for Rapid Data Transfer DS1921G-F5N -40C to +85C F5 Can Communicates to Host with a Single Digital Signal Denotes a RoHS-compliant device that include lead(Pb) that Up to 15.4kbps at Standard Speed or Up to is exempt under the RoHS requirements. 125kbps in Overdrive Mode Using 1-Wire Protocol A NIST traceability certificate is available for the DS1921G-F5N. See Application Note 4629 for details. Common iButton Device Features appear at end of data Examples of Accessories sheet. PART ACCESSORY DS9096P Self-Stick Adhesive Pad DS9101 Multipurpose Clip DS9093RA Mounting Lock Ring DS9093A Snap-In Fob DS9092 iButton Probe Pin Configuration appears at end of data sheet. Thermochron, iButton, and 1-Wire are registered trademarks of Maxim Integrated Products, Inc. 19-5101 Rev 9 3/15Thermochron iButton Device DS1921G Absolute Maximum Ratings IO Voltage Range Relative to GND ..........................-0.5V to +6V Operating Temperature Range ..........................-40C to +85C* IO Sink Current....................................................................20mA Storage Temperature Range..............................-40C to +50C* *Storage or operation above +50C 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. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Electrical Characteristics (V = +2.8V to +5.25V, T = -40C to +85C.) PUP A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS IO PIN: GENERAL DATA 1-Wire Pullup Resistance R (Notes 1, 2) 2.2 k PUP Input Capacitance C (Notes 3, 4) 100 800 pF IO Input Load Current I IO pin at V (Note 5) 10 A L PUP V > 4.5V 1.14 2.70 High-to-Low Switching Threshold PUP V V TL (Notes 4, 6, 7, 8) 0.71 2.70 Input Low Voltage V (Notes 1, 6, 9) 0.30 V IL V > 4.5V 1.00 2.70 Low-to-High Switching Threshold PUP V V TH (Notes 4, 6, 7, 10) 0.66 2.70 Output Low Voltage at 4mA V (Notes 6, 11) 0.4 V OL Standard speed, R = 2.2k 5 PUP Overdrive speed, R = 2.2k 2 PUP Recovery Time (Notes 1, 4) t s REC Overdrive speed, directly prior to reset 5 pulse R = 2.2k PUP Standard speed 65 Time-Slot Duration (Notes 1, 12) t s SLOT Overdrive speed 8 IO PIN: 1-Wire RESET, PRESENCE-DETECT CYCLE Standard speed, V > 4.5V 480 640 PUP Standard speed 540 640 Reset Low Time (Notes 1,12) t s RSTL Overdrive speed, V > 4.5V 48 80 PUP Overdrive speed 58 80 Standard speed 15 60 Presence-Detect High t s PDH Time (Note 12) Overdrive speed 1.1 6 Standard speed 60 270 Presence-Detect Low t s PDL Overdrive speed, V > 4.5V 7.5 24 PUP Time (Note 12) Overdrive speed 7.5 32 Standard speed 60 75 Presence-Detect t s MSP Sample Time (Notes 1, 4) Overdrive speed 6 8.6 www.maximintegrated.com Maxim Integrated 2