DS2505+TR MAXIM [Maxim Integrated Products], DS2505+TR Datasheet
DS2505+TR
Related parts for DS2505+TR
DS2505+TR Summary of contents
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FEATURES 16384 bits Electrically Programmable Read Only Memory (EPROM) communicates with the economy of one signal plus ground Unique, factory-lasered and tested 64-bit registration number (8-bit family code + 48-bit serial number + 8-bit CRC tester) assures ...
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SILICON LABEL DESCRIPTION The DS2505 16Kb Add–Only Memory identifies and stores relevant information about the product to which it is associated. This lot or product specific information can be accessed with minimal interface, for example a single port pin of ...
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This protocol is described in the ROM functions flow chart (Figure 8). The 1-Wire bus master must first provide one of four ROM function commands: 1) Read ROM, 2) Match ROM, 3) Search ROM ...
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HIERARCHICAL STRUCTURE FOR 1-WIRE PROTOCOL Figure 2 64-BIT LASERED ROM Figure 3 8-Bit CRC Code MSB 16384-BITS EPROM The memory map in Figure 4 shows the 16384-bit EPROM section of the DS2505 which is configured as 64 pages of 32 ...
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EPROM STATUS BYTES In addition to the 16384 bits of data memory the DS2505 provides 704 bits of Status Memory accessible with separate commands. The EPROM Status Bytes can be read or programmed to indicate various conditions to the software ...
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The Status Memory address range of the DS2505 extends from 000 to 13FH. The memory locations 008H to 01FH, 028H to 03FH, 048H to 0FFH and 140H to 7FFH are physically not implemented. Reading these locations will usually result in ...
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MEMORY FUNCTION COMMANDS The “Memory Function Flow Chart” (Figure 5) describes the protocols necessary for accessing the various data fields within the DS2505. The Memory Function Control section, 8-bit scratchpad, and the Program Voltage Detect circuit combine to interpret the ...
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MEMORY FUNCTION FLOW CHART Figure ...
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MEMORY FUNCTION FLOW CHART Figure 5 (cont’ ...
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MEMORY FUNCTION FLOW CHART Figure 5 (cont’ ...
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Note that the initial pass through the Read Status flow chart will generate a 16-bit CRC value that is the result of clearing the CRC generator and then shifting in the command byte followed by the 2 address bytes, and ...
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With the next 24 read data time slots the master will receive the Redirection Byte of the next page followed by a 16-bit CRC of the Redirection Byte. After this, data is again read from the 16,384-bit EPROM data field ...
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As the DS2505 receives this byte of data into the scratchpad, it also shifts the data into the CRC generator that has been preloaded with the current address and the result is a 16-bit CRC of the new data byte ...
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EPROM Status address sent least significant bit first. This byte contains the logical AND of all bytes written to this EPROM Status Byte address. If the EPROM Status Byte contains 1s in bit ...
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Hardware Configuration The 1-Wire bus has only a single line by definition important that each device on the bus be able to drive it at the appropriate time. To facilitate this, each device attached to the 1-Wire bus ...
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DS2505 EQUIVALENT CIRCUIT Figure 6 BUS MASTER CIRCUIT Figure ...
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ROM FUNCTIONS FLOW CHART Figure ...
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Match ROM [55H] The Match ROM command, followed by a 64-bit ROM sequence, allows the bus master to address a specific DS2505 on a multidrop bus. Only the DS2505 that exactly matches the 64-bit ROM sequence will respond to the ...
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Note that due to the high voltage programming requirements for any 1-Wire EPROM ...
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READ/WRITE TIMING DIAGRAM Figure 10 (cont’d) NOTE: For read-data time slots the optimal sampling point for the master is as close as possible to the end of the t period without exceeding the 15 µs window. For the case of ...
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PROGRAM PULSE TIMING DIAGRAM Figure 11 CRC GENERATION With the DS2505 there are two different types of CRCs (Cyclic Redundancy Checks). One CRC is an 8-bit type and is stored in the most significant byte of the 64-bit ROM. The ...
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When reading the data memory of the DS2505 with the Extended Read Memory command, there are two situations where a 16-bit CRC is transmitted. One 16-bit CRC follows each Redirection Byte; another 16-bit CRC is received after the last byte ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * This is a stress rating only and functional operation of the device at these or any other conditions outside those indicated in the ...
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NOTES: 1. All voltages are referenced to ground external pullup voltage PUP may not reproduce the correct memory contents. Therefore, under low voltage conditions recommended to set either the most significant bit or ...