DS28EA00U+ Maxim Integrated Products, DS28EA00U+ Datasheet
DS28EA00U+
Specifications of DS28EA00U+
Related parts for DS28EA00U+
DS28EA00U+ Summary of contents
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... Data Communication Equipment Process Temperature Monitoring HVAC Systems Ordering Information PART TEMP RANGE DS28EA00U+ -40°C to +85°C DS28EA00U+T&R -40°C to +85°C + Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel 1-Wire MASTER PX. Y MICROCONTROLLER NOTE: SCHEMATIC SHOWS PIO PINS WIRED FOR SEQUENCE-DETECT FUNCTION ...
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Digital Thermometer with Sequence Detect and PIO ABSOLUTE MAXIMUM RATINGS IO Voltage Range to GND ........................................-0.5V to +6V IO Sink Current....................................................................20mA Maximum PIOA or PIOB Pin Current...................................20mA Maximum Current Through GND Pin ..................................40mA Stresses beyond those listed under “Absolute ...
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ELECTRICAL CHARACTERISTICS (continued -40°C to +85°C.) (Note 1) A PARAMETER SYMBOL Presence-Detect High Time Presence-Detect Fall Time (Notes 3, 15) Presence-Detect Low Time Presence-Detect Sample Time (Notes 2, 16) IO PIN: 1-Wire WRITE Write-Zero Low Time (Notes 2, ...
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Digital Thermometer with Sequence Detect and PIO ELECTRICAL CHARACTERISTICS (continued -40°C to +85°C.) (Note 1) A Note 1: Specifications -40°C are guaranteed by design and not production tested. A Note 2: System requirement. Note ...
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... ROM, Overdrive-Match ROM. Upon completion of an overdrive ROM command exe- cuted at standard speed, the device enters overdrive mode, where all subsequent communication occurs at iButton is a registered trademark of Maxim Integrated Products, Inc. _______________________________________________________________________________________ 1-Wire Digital Thermometer with Sequence Detect and PIO FUNCTION a higher speed ...
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Digital Thermometer with Sequence Detect and PIO DS28EA00 PIOB (EN) CONFIGURATION COMMAND LEVEL: 1-Wire ROM FUNCTION COMMANDS (SEE FIGURE 11) DS28EA00-SPECIFIC CONTROL FUNCTION COMMANDS (SEE FIGURE 9) Figure 1. Hierarchical Structure for 1-Wire Protocol 6 _______________________________________________________________________________________ ...
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MSB 8-BIT CRC CODE MSB LSB MSB Figure 2. 64-Bit Registration Number 1ST 2ND 3RD STAGE STAGE STAGE Figure 3. 1-Wire CRC Generator Memory Description The memory map of the DS28EA00 is shown in ...
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Digital Thermometer with Sequence Detect and PIO ADDRRESS BIT 7 BIT ADDRRESS BIT 7 BIT Table 1. Temperature/Data Relationship TEMPERATURE (°C) ...
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ADDRRESS BIT 7 BIT The functional assignments of the individual bits are explained in the table below. Bits [4:0] and bit 7 have BIT DESCRIPTION BIT(S) R1, R0: Temperature [6:5] Converter Resolution Each PIO consists of ...
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Digital Thermometer with Sequence Detect and PIO The power-on default chain state is OFF, where PIOA and PIOB are solely controlled through the PIO Access Read and Write commands. In the chain ON state, PIOA is pulled high to ...
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BIT 7 BIT 6 BIT 5 COMPLEMENT BIT 7 BIT 6 BIT PIO Access Read [F5h] This command reads the PIO logical status and reports it together with the state of the PIO ...
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Digital Thermometer with Sequence Detect and PIO MOST SIGNIFICANT 2 BITS OF INVERTED PIO OUTPUT DATA BYTE IO PIO Figure 7. PIO Access Write Timing Diagram as the new PIO output state arrives in its true form at the ...
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BUS MASTER Tx CONTROL FUNCTION COMMAND 4Eh N WRITE SCRATCHPAD? Y DS28EA00 SETS BYTE ADDRESS = 2 MASTER Tx DATA BYTE TO SCRATCHPAD Y MASTER Tx RESET? N BYTE Y ADDRESS = 4? N DS28EA00 INCREMENTS BYTE ADDRESS N MASTER ...
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Digital Thermometer with Sequence Detect and PIO FROM FIGURE 9a TEMPERATURE MASTER DECISION. THE MASTER NEEDS TO KNOW WHETHER V DD POWER IS AVAILABLE DS28EA00 STARTS TEMPERATURE CONVERSION CONVERSION COMPLETED? N MASTER Rx "0"s MASTER Tx RESET? ...
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FROM FIGURE 9b B8h N RECALL EEPROM? Y DS28EA00 STARTS RECALL EEPROM TO SCRATCHPAD RECALL Y COMPLETED? N MASTER Rx "0"s MASTER Rx "1"s Y MASTER Tx RESET? N MASTER Rx "1"s TO FIGURE 9b *SEE THE COMMAND DESCRIPTION FOR ...
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Digital Thermometer with Sequence Detect and PIO FROM FIGURE 9c CHAIN COMMAND? MASTER Tx CHAIN CONTROL BYTE MASTER Tx INVERTED CHAIN CONTROL BYTE TRANSMISSION CONTROL BYTE VALID CHAIN CONTROL BYTE CODES: 3Ch OFF 5Ah ON 96h DONE DS28EA00 UPDATES ...
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Bus System The 1-Wire bus is a system that has a single bus master and one or more slaves. In all instances the DS28EA00 is a slave device. The bus master is typically a micro- controller. The discussion of ...
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Digital Thermometer with Sequence Detect and PIO 1-Wire ROM Function Commands Once the bus master has detected a presence, it can issue one of the eight ROM function commands that the DS28EA00 supports. All ROM function commands are 8 ...
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This command can save time in a single-drop bus sys- tem by allowing the bus master to access the control functions without providing the 64-bit ROM code. If more than one slave is present on the bus and, for example, ...
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Digital Thermometer with Sequence Detect and PIO FROM CONTROL FUNCTIONS FLOWCHART (FIGURE 9) BUS MASTER Tx ROM FUNCTION COMMAND 33h N READ ROM COMMAND? Y DS28EA00 Tx FAMILY CODE (1 BYTE) DS28EA00 Tx SERIAL NUMBER (6 BYTES) DS28EA00 Tx ...
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TO FIGURE 11a 0Fh FROM FIGURE 11a CONDITIONAL READ ROM CHAIN = ON LOW? Y DS28EA00 Tx FAMILY CODE (1 BYTE) DS28EA00 Tx SERIAL NUMBER (6 BYTES) DS28EA00 Tx CRC BYTE FROM FIGURE 11a ...
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Digital Thermometer with Sequence Detect and PIO 1-Wire Signaling The DS28EA00 requires strict protocols to ensure data integrity. The protocol consists of four types of signaling on one line: reset sequence with reset pulse and pres- ence pulse, write-zero, ...
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WRITE-ONE TIME SLOT t W1L V PUP V IHMASTER ILMAX RESISTOR WRITE-ZERO TIME SLOT V PUP V IHMASTER ILMAX RESISTOR READ-DATA TIME SLOT t ...
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Digital Thermometer with Sequence Detect and PIO For a write-one time slot, the voltage on the data line must have crossed the V threshold before the write- TH one low time t is expired. For a write-zero time W1LMAX ...
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V PUP CASE A 0V Figure 14. Noise Suppression Scheme through R of the PIOA pin charges the PIOA/PIOB CO connections to logic 1 level at all devices except for the first device in the chain. ...
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Digital Thermometer with Sequence Detect and PIO Command-Specific 1-Wire Communication Protocol—Legend SYMBOL RST 1-Wire reset pulse generated by master PD 1-Wire presence pulse generated by slave SELECT Command and data to satisfy the ROM function protocol SKIPR ROM function ...
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Digital Thermometer with Write Scratchpad RST PD SELECT WSP <3 Bytes> Read Scratchpad RST PD SELECT RSP <8 Bytes> Copy Scratchpad (Parasite Powered) Wait t RST PD SELECT CPS PROGMAX Copy Scratchpad (Local V Powered) DD RST PD SELECT ...
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Digital Thermometer with Sequence Detect and PIO PIO Access Write (Invalid Data Byte) RST PD SELECT PIOW <PIO Output Data> The PIO Access Write command is ignored by the device while in chain ON or chain DONE state. Change ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 29 © 2009 Maxim Integrated Products ...