DS2502G-00C+T&R Maxim Integrated, DS2502G-00C+T&R Datasheet
DS2502G-00C+T&R
Specifications of DS2502G-00C+T&R
Related parts for DS2502G-00C+T&R
DS2502G-00C+T&R Summary of contents
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... Pin Configurations appear at end of data sheet. Functional Diagrams continued at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com. 19-5075; Rev 12/11 ...
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... ORDERING INFORMATION PART TEMP RANGE PIN-PACKAGE DS2502+ -40°C to +85°C DS2502+T&R -40°C to +85°C DS2502G+T&R -40°C to +85°C DS2502P+ -40°C to +85°C DS2502P+T&R -40°C to +85°C DS2502R+T&R -40°C to +85°C DS2502S+ -40°C to +85°C DS2502S+T&R -40°C to +85°C DS2502X1 -40° ...
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... Bus System.” The memory functions required to read and program the EPROM sections of the DS2502 are not accessible until the ROM function protocol has been satisfied. This protocol is described in the ROM functions flow chart (Figure 9). The 1- Wire bus master must first provide one of four ROM function commands: 1) Read ROM, 2) Match ROM, 3) Search ROM Skip ROM ...
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HIERARCHICAL STRUCTURE FOR 1-WIRE PROTOCOL Figure 2 64-BIT LASERED ROM Figure 3 8–Bit CRC Code MSB 1-WIRE CRC GENERATOR Figure 4 48–Bit Serial Number LSB MSB 8–Bit Family Code (09h) LSB MSB LSB ...
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... The hardware of the DS2502 makes no decisions based on the contents of the Page Address Redirection Bytes. These additional bytes of Status EPROM technology, bits within a page can be changed from a logical logical 0 by programming, but cannot be changed back. Therefore not possible to simply rewrite a page if the data requires changing or updating, but with space permitting, an entire page of data can be redirected to another page within the DS2502 by writing the one’ ...
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Writing data involves not only issuing the correct command sequence by also providing a 12-volt programming voltage at the appropriate times. To execute a write sequence, a byte of data is first loaded into the scratchpad and then programmed ...
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MEMORY FUNCTION FLOW CHART Figure 6 ...
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MEMORY FUNCTION FLOW CHART Figure 6 (cont’d) LEGEND: DECISION MADE BY THE MASTER DECISION MADE BY DS2502 ...
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MEMORY FUNCTION FLOW CHART Figure 6 (cont’d) ...
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... DS2502 starting at the supplied address and continuing until the end of the EPROM Status data field is reached. At that point the bus master will receive an 8-bit CRC that is the result of shifting into the CRC generator all of the data bytes from the initial starting byte through the final factory-programmed byte that contains the 00h value ...
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... Wire bus for 480 µs) is issued by the bus master. Prior to programming, the entire unprogrammed 1024- bit EPROM data field will appear as logical 1s. For each bit in the data byte provided by the bus master that is set to a logical 0, the corresponding bit in the selected byte of the 1024-bit EPROM will be programmed to a logical 0 after the programming pulse has been applied at that byte location. After the 480 µ ...
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... If the CRC received by the bus master is correct, a programming pulse (12 volts on the 1- Wire bus for 480 µs) is issued by the bus master. Prior to programming, the first 7 bytes of the EPROM Status data field will appear as logical 1s. For each bit in the data byte provided by the bus master that is set to a logical 0, the corresponding bit in the selected byte of the EPROM Status data field will be programmed to a logical 0 after the programming pulse has been applied at the byte location ...
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... EPROM byte. The decision to continue is again made entirely by the bus master, therefore if the EPROM data byte does not match the supplied data byte but the master continues with the Write Status command, incorrect programming could occur within the DS2502 ...
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... If the bus master is also required to perform programming of the EPROM portions of the DS2502, a programming supply capable of delivering milliamps at 12 volts for 480 µs is required. The idle state for the 1-Wire bus is high. If, for any reason, a transaction needs to be suspended, the bus MUST be left in the idle state if the transaction is to resume. If this does not occur and the bus is left low for more than 120 µ ...
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DS2502 EQUIVALENT CIRCUIT Figure 7 BUS MASTER CIRCUIT Figure 8 ...
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ROM FUNCTIONS FLOW CHART Figure 9 ...
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... If the data bit the device will leave the read data time slot unchanged. PROGRAM PULSE To copy data from the 8-bit scratchpad to the 1024-bit EPROM Memory or Status Memory, a program pulse of 12 volts is applied to the data line after the bus master has confirmed that the CRC for the current byte is correct ...
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... CRC commands to confirm that these bytes have been received correctly. The CRC generator on the DS2502 is also used to provide verification of error-free data transfer as each page of data from the 1024- bit EPROM is sent to the bus master during a Read Data/Generate 8-Bit CRC command, and for the 8 bytes of information in the status memory field. ...
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READ/WRITE TIMING DIAGRAM Figure 11 Write-one Time Slot Write-zero Time Slot Read-data Time Slot RESISTOR MASTER DS2502 DS2502 SAMPLING WINDOW 60 µs ≤ t < 120 µs SLOT 1 µs ≤ t < 15 µs LOW1 1 µs ≤ t ...
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PROGRAM PULSE TIMING DIAGRAM Figure 12 ...
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... DC ELECTRICAL CHARACTERISTICS PARAMETER Pullup Voltage Logic 1 Logic 0 Output Logic Low @ 4 mA Input Load Current Operating Charge Programming Voltage @ 10 mA Valid EPROM Read Voltage CAPACITANCE PARAMETER Data (1-Wire) AC ELECTRICAL CHARACTERISTICS PARAMETER Time Slot Write 1 Low Time Write 0 Low Time Read Data Valid ...
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... µs after power has been applied the parasite capacitance will not affect may have to be reduced to as much as 0.5V to always ILMAX PUP =2.5V or higher, but EPROM data read is recovery time above the minimum V REC PUP ...
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PACKAGE INFORMATION For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the ...
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... Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 © 2011 Maxim Integrated DESCRIPTION to 960µs maximum. RSTL to 960µs maximum. The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc. PAGES CHANGED all ...