DS18S20Z+ Maxim Integrated Products, DS18S20Z+ Datasheet
DS18S20Z+
Specifications of DS18S20Z+
Related parts for DS18S20Z+
DS18S20Z+ Summary of contents
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... Applications that can benefit from this feature include HVAC environmental controls, temperature monitoring systems inside buildings, equipment, or machinery, and process monitoring and control systems. 1-Wire is a registered trademark of Maxim Integrated Products, Inc. High-Precision 1-Wire Digital Thermometer PIN CONFIGURATIONS MAXIM ...
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... DS18S20Z DS18S20Z+ DS18S20Z/T&R DS18S20Z+T&R +Denotes a lead(Pb)-free/RoHS-compliant package. A “+” appears on the top mark of lead(Pb)-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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Figure 1. DS18S20 Block Diagram V PU PARASITE POWER 4.7k CIRCUIT DQ INTERNAL V GND OPERATION—MEASURING TEMPERATURE The core functionality of the DS18S20 is its direct-to-digital temperature sensor. The temperature sensor output has 9-bit resolution, which ...
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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 TEMPERATURE DIGITAL OUTPUT (°C) +85.0* 0000 0000 1010 1010 +25.0 0000 ...
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POWERING THE DS18S20 The DS18S20 can be powered by an external supply on the V mode, which allows the DS18S20 to function without a local external supply. Parasite power is very useful for applications that require remote temperature sensing or ...
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Figure 4. Supplying the Parasite-Powered DS18S20 During Temperature Conversions µP Figure 5. Powering the DS18S20 with an External Supply µP 64-BIT LASERED ROM CODE Each DS18S20 contains a unique 64-bit code (see Figure 6) stored in ROM. The least significant ...
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MEMORY The DS18S20’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 Note that if the DS18S20 alarm function is not ...
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CRC GENERATION CRC bytes are provided as part of the DS18S20’s 64-bit ROM code and in the 9th byte of the scratchpad memory. The ROM code CRC is calculated from the first 56 bits of the ROM code and is ...
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BUS SYSTEM The 1-Wire bus system uses a single bus master to control one or more slave devices. The DS18S20 is always a slave. When there is only one slave on the bus, the system is referred to as ...
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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 DS18S20s on the bus perform simultaneous temperature conversions by ...
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COPY SCRATCHPAD [48h] This command copies the contents of the scratchpad T 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 the 1-Wire bus ...
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SIGNALING The DS18S20 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. All these signals, with the ...
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READ-TIME SLOTS The DS18S20 can only transmit data to the master when the master issues read-time slots. Therefore, the master must generate read-time slots immediately after issuing a Read Scratchpad [BEh] or Read Power Supply [B4h] command, so that the ...
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Figure 12. Detailed Master Read 1 Timing V PU 1-WIRE BUS GND T INT Figure 13. Recommended Master Read 1 Timing V PU 1-WIRE BUS GND INT RC small small > 1µ 15µs VIH ...
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Figure 14. ROM Commands Flowchart Initialization Sequence 33h N READ ROM COMMAND Y DS18S20 T X FAMILY CODE 1 BYTE DS18S20 T X SERIAL NUMBER 6 BYTES DS18S20 T X CRC BYTE MASTER T X RESET PULSE DS18S20 T X ...
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Figure 15. DS18S20 Function Commands Flowchart 44h MASTER T CONVERT X FUNCTION TEMPERATURE COMMAND ? Y N PARASITE POWER ? DS18S20 BEGINS CONVERSION DEVICE N CONVERTING TEMPERATURE ? Y MASTER MASTER R “0s” R “1s” B4h N READ ...
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DS18S20 OPERATION EXAMPLE 1 In this example there are multiple DS18S20s on the bus and they are using parasite power. The bus master initiates a temperature conversion in a specific DS18S20 and then reads its scratchpad and recalculates the CRC ...
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DS18S20 OPERATION EXAMPLE 3 In this example there is only one DS18S20 on the bus and it is using parasite power. The bus master initiates a temperature conversion then reads the DS18S20 scratchpad and calculates a higher resolution result using ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground ........................................................................................ -0.5V to +6.0V Continuous Power Dissipation (T = +70°C) A 8-Pin SO (derate 5.9mW/°C above +70°C) .......................................................................................... 470.6mW 3-Pin TO-92 (derate 6.3mW/°C above +70°C)..................................................................................... 500mW Operating Temperature Range ...
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AC ELECTRICAL CHARACTERISTICS—NV MEMORY (V = 3.0V to 5.5V -55°C to +100°C, unless otherwise noted PARAMETER NV Write Cycle Time EEPROM Writes EEPROM Data Retention AC ELECTRICAL CHARACTERISTICS (V = 3.0V to 5.5V -55°C ...
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Figure 17. Timing Diagrams PACKAGE INFORMATION For the latest package outline information and land patterns the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless ...
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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 © 2010 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. DS18S20 PAGES CHANGED ...