DS18B20U+ Maxim Integrated Products, DS18B20U+ Datasheet
DS18B20U+
Specifications of DS18B20U+
Related parts for DS18B20U+
DS18B20U+ Summary of contents
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... Software Compatible with the DS1822 Applications Include Thermostatic Controls, Industrial Systems, Consumer Products, Thermometers, or Any Thermally Sensitive System PIN CONFIGURATIONS MAXIM 18B20 equipment (BOTTOM VIEW) TO-92 (DS18B20) 1-Wire is a registered trademark of Maxim Integrated Products, Inc DS18B20 N.C. N. N. GND ...
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... DS18B20/T&R DS18B20+T&R DS18B20-SL/T&R DS18B20-SL+T&R DS18B20U DS18B20U+ DS18B20U/T&R DS18B20U+T&R DS18B20Z DS18B20Z+ DS18B20Z/T&R DS18B20Z+T&R +Denotes a lead-free package. A “+” will appear on the top mark of lead-free packages. T&R = Tape and reel. *TO-92 packages in tape and reel can be ordered with straight or formed leads. Choose “SL” for straight leads. Bulk TO-92 orders are straight leads only ...
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The 1-Wire bus protocol, including detailed explanations of the commands and “time slots,” is covered in the 1-Wire Bus System section. Another feature of the DS18B20 is the ability to operate without an external power supply. ...
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Figure 2. Temperature Register Format BIT 7 BIT BYTE 2 2 BIT 15 BIT 14 MS BYTE SIGN Table 1. Temperature/Data Relationship DIGITAL OUTPUT TEMPERATURE (°C) +125 0000 0111 1101 0000 +85* 0000 ...
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The master device can check the alarm flag status of all DS18B20s on the bus by issuing an Alarm Search [ECh] command. Any DS18B20s with a set alarm flag will respond to the command, so the master can determine exactly ...
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Figure 4. Supplying the Parasite-Powered DS18B20 During Temperature Conversions µP Figure 5. Powering the DS18B20 with an External Supply µP 64-BIT LASERED ROM CODE Each DS18B20 contains a unique 64–bit code (see Figure 6) stored in ROM. The least significant ...
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MEMORY The DS18B20’s memory is organized as shown in Figure 7. The memory consists of an SRAM scratchpad with nonvolatile EEPROM storage for the high and low alarm trigger registers (T and configuration register. Note that if the DS18B20 alarm ...
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CONFIGURATION REGISTER Byte 4 of the scratchpad memory contains the configuration register, which is organized as illustrated in Figure 8. The user can set the conversion resolution of the DS18B20 using the R0 and R1 bits in this register as ...
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Application Note 27: Understanding and Using Cyclic Redundancy Checks with Maxim iButton Products. Figure 9. CRC Generator (MSB) 1-WIRE BUS SYSTEM The 1-Wire bus system uses a single bus master to control one or more slave devices. ...
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... Only the slave that exactly matches the 64-bit ROM code sequence will respond to the function command issued by the master; all other slaves on the bus will wait for a reset pulse. iButton is a registered trademark of Maxim Integrated Products, Inc. ® Book of Standards at www.maxim-ic.com/ibuttonbook. After every ...
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SKIP ROM [CCh] The master can use this command to address all devices on the bus simultaneously without sending out any ROM code information. For example, the master can make all DS18B20s on the bus perform simultaneous temperature conversions by ...
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COPY SCRATCHPAD [48h] This command copies the contents of the scratchpad T to EEPROM. If the device is being used in parasite power mode, within 10µs (max) after this command is issued the master must enable a strong pullup on ...
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Figure 11. ROM Commands Flowchart Initialization Sequence 33h N READ ROM MATCH ROM COMMAND Y MASTER T DS18B20 T X FAMILY CODE 1 BYTE DS18B20 T X SERIAL NUMBER 6 BYTES MASTER T DS18B20 T X CRC BYTE MASTER T ...
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Figure 12. DS18B20 Function Commands Flowchart 44h MASTER T CONVERT X FUNCTION TEMPERATURE COMMAND ? Y N PARASITE POWER ? DS18B20 BEGINS CONVERSION DEVICE N CONVERTING TEMPERATURE ? Y MASTER MASTER R “0s” R “1s” B4h N READ ...
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SIGNALING The DS18B20 uses a strict 1-Wire communication protocol to ensure data integrity. Several signal types are defined by this protocol: reset pulse, presence pulse, write 0, write 1, read 0, and read 1. The bus master initiates all ...
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The DS18B20 samples the 1-Wire bus during a window that lasts from 15µs to 60µs after the master initiates the write time slot. If the bus is high during the sampling window written to the DS18B20. If ...
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DS18B20 is valid for 15µs after the falling edge that initiated the read time slot. Therefore, the master must release the bus and then sample the bus state within 15µs from the start of the slot. Figure ...
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DS18B20 OPERATION EXAMPLE 1 In this example there are multiple DS18B20s on the bus and they are using parasite power. The bus master initiates a temperature conversion in a specific DS18B20 and then reads its scratchpad and recalculates the CRC ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground .................................................................. -0.5V to +6.0V Operating Temperature Range ....................................................................................... -55°C to +125°C Storage Temperature Range ........................................................................................... -55°C to +125°C Solder Temperature ..................................................... Refer to the IPC/JEDEC J-STD-020 Specification. These are ...
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AC ELECTRICAL CHARACTERISTICS—NV MEMORY PARAMETER NV Write Cycle Time EEPROM Writes EEPROM Data Retention AC ELECTRICAL CHARACTERISTICS PARAMETER Temperature Conversion Time Time to Strong Pullup On Time Slot Recovery Time Write 0 Low Time Write 1 Low Time Read Data ...
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Figure 18. Timing Diagrams DS18B20 ...
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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 © 2008 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. DS18B20 PAGES CHANGED 19 5 ...