DS18S20Z Maxim Integrated Products, DS18S20Z Datasheet
DS18S20Z
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DS18S20Z Summary of contents
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... Maxim Integrated Products, Inc. High-Precision 1-Wire Digital Thermometer PIN CONFIGURATIONS MAXIM DS1820 (BOTTOM VIEW) TO-92 (DS18S20 DS18S20 N. (150 mils) (DS18S20Z N.C. 8 N.C. 7 N.C. 6 GND 5 ...
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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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... The temperature data is stored as a 16-bit sign-extended two’s complement number in the temperature register (see Figure 2). The sign bits (S) indicate if the temperature is positive or negative: for positive numbers and for negative numbers Table 1 gives examples of digital output data and the corresponding temperature reading. ...
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... Only bits 8 through 1 of the temperature register are used in the T are 8-bit registers. If the measured temperature is lower than or equal to T condition exists and an alarm flag is set inside the DS18S20. This flag is updated after every temperature measurement; therefore, if the alarm condition goes away, the flag will be turned off after the next temperature conversion ...
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... The master needs this information to determine if the strong bus pullup should be used during temperature conversions. To get this information, the master can issue a Skip ROM [CCh] command followed by a Read Power Supply [B4h] command followed by a “read-time slot”. ...
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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 8 bits of the ROM code contain the DS18S20’s 1-Wire family code: 10h. The next 48 bits contain a unique serial number ...
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... Note that if the DS18S20 alarm function is not used, the T memory. All memory commands are described in detail in the DS18S20 Function Commands section. Byte 0 and byte 1 of the scratchpad contain the LSB and the MSB of the temperature register, respectively. These bytes are read-only. Bytes 2 and 3 provide access are reserved for internal use by the device and cannot be overwritten ...
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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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... This command initiates a single temperature conversion. Following the conversion, the resulting thermal data is stored in the 2-byte temperature register in the scratchpad memory and the DS18S20 returns to its low-power idle state. If the device is being used in parasite power mode, within 10µs (max) after this ...
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... Signals DS18S20 power Supply supply mode to the master. For parasite-powered DS18S20s, the master must enable a strong pullup on the 1-Wire bus during temperature Note 1: conversions and copies from the scratchpad to EEPROM. No other bus activity may take place during this time. Note 2: The master can interrupt the transmission of data at any time by issuing a reset. ...
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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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... X B4h N READ POWER SUPPLY ? PARASITE POWERED ? MASTER MASTER R “1s” R “0s” MASTER ENABLES STRONG PULLUP ON DQ DS18S20 CONVERTS TEMPERATURE PROGRESS Y MASTER DISABLES STRONG PULLUP MASTER N B8h 2 RECALL MASTER BEGINS DATA 2 RECALL FROM E PROM DEVICE N BUSY RECALLING DATA ? Y MASTER MASTER R “0s” ...
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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 to verify the data. MASTER MODE ...
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... 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 the data from the temperature, COUNT REMAIN and COUNT PER °C registers. ...
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... DQ should be within the following ranges: GND ≤ DQ ≤ GND + 0. minimize I DDS – 0.3V ≤ DQ ≤ Active current refers to supply current during active temperature conversions or EEPROM writes. 10) DQ line is high (“high-Z” state). 11) Drift data is based on a 1000-hour stress test at +125°C with V CONDITIONS MIN TYP Local Power +3.0 Parasite Power +3 ...
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... SLOT t REC t LOW0 t LOW1 t RDV t RSTH t RSTL t PDHIGH t PDLOW C IN/OUT > 960µs, a power-on reset may occur. DS18S20 Typical Error Curve Mean Error Temperature (° MIN TYP MAX 2 10 50k 10 MIN TYP MAX UNITS 750 ms µs 10 µs 60 120 µs 1 µs 60 120 µs ...
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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 ...