View DS2502-E48_9187.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

DS2502-E48 48-Bit Node Address Chip
www.maxim-ic.com
FEATURES
Factory programmed 48-bit node address chip with 768 bits user-programmable OTPEPROM communicates with the economy of one signal plus ground Provides valid MAC-48/EUI-48 ETHERNET address Unique, factory lasered and tested 64-bit registration number assures absolute traceability because no two parts are alike Built-in multidrop controller ensures compatibility with other 1-Wire(R) products Device is an "add-only" memory where additional data can be programmed into EPROM without disturbing existing data Reduces control, address, data, power and programming signals to a single pin Directly connects to a single port pin of a microprocessor and communicates at up to 16.3kbps Presence detector acknowledges when reader first applies voltage Low cost TO-92 or TSOC surface mount packages Reads over a wide voltage range of 2.8V to 6.0V from -40C to +85C; programs at 11.5V to 12.0V from -40C to + 50C
PIN CONFIGURATION
TO-92

BOTTOM VIEW TSOC PACKAGE
TOP VIEW
ORDERING INFORMATION
DS2502-E48 TO-92 package DS2502P-E48 TSOC package DS2502P-E48/T&R Tape-and-Reel version of DS2502P-E48
GLOBAL IDENTIFIER DESCRIPTION
The DS2502-E48 is a variant of the DS2502 1024-bit add-only memory. It differs from the standard DS2502 in its custom ROM family code 89H, and the UniqueWare Identifier 5E7H in place of the upper 12 bits of the standard ROM serialization field. Otherwise, the electrical and logical behavior is identical to that of the DS2502. For technical details please refer to the DS2502 data sheet.
1-Wire is a registered trademark of Dallas Semiconductor. Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.
1 of 2
021103
DS2502-E48
The first 32 bytes of the DS2502-E48's EPROM memory contain a globally unique 48-bit node address and are write-protected. The data structure follows the conventions of UniqueWare devices using Default Data Structure (Figure 1).
Figure 1. NODE ADDRESS CHIP DATA STRUCTURE
CRC16 (unused) 19 bytes FFH high address MSB 2 bytes LSB Company ID Value MSB LSB 3 bytes constant 006035H Extension ID Value MSB LSB 3 bytes serialization Project ID MSB LSB 4 bytes constant 00001129H Length 1 byte 0AH low address
The data record starts with a length byte (0AH) and the 4-byte UniqueWare Project ID 00001129H. The next 6 bytes contain the 48-bit node address which consists of an incrementing 24-bit extension identifier and the IEEE-assigned 24-bit company ID value 006035H. A 16-bit CRC ends the data record. The remaining bytes of the 32-byte memory page remain unprogrammed. Neither the 24-bit extension identifier nor the 24-bit company ID are related to the 64-bit ROM registration number. The ROM registration number is used to provide a unique address to access the DS2502-E48 when multidropped on a 1-Wire bus. The company ID value 006035H has been assigned by the IEEE to Dallas Semiconductor. If a different company ID value is required, See App Note 99: UniqueWare Project Setup Manual. http://dbserv.maxim-ic.com/appnotes.cfm/appnote_number/518/ln/en
EXAMPLE
Assume that a manufacturer's company ID value is 006035H and the 24-bit extension identifier is 67ABCDH. The 48-bit node address value generated from these two numbers is 00603567ABCDH, whose byte and bit representations are illustrated in Figure 2.
Figure 2. SAMPLE NODE ADDRESS VALUE
MOST SIGNIFICANT BYTE 00 60 0000 0000 0110 0000 MOST SIGNIFICANT BIT 35 0011 0101 67 0110 0111 LEAST SIGNIFICANT BYTE AB CD 1010 1011 1100 1101 LEAST SIGNIFICANT BIT HEX BINARY
This information is stored in the DS2502-E48 as 48-bit number with the least significant byte at the lower address. Including the length byte and the CRC, the complete set of data is shown in Figure 3.
Figure 3. PHYSICAL ADDRESS AND DATA MAPPING INSIDE THE DEVICE
ADDRESS DATA 0C XX 0B XX 0A 00 09 60 08 35 07 67 06 AB 05 CD 04 00 03 00 02 11 01 29 00 0A
XX XX = CRC16, value depends on actual data
The four bytes at memory addresses 01 to 04 contain the UniqueWare Project ID 00001129H. The two bytes at addresses 0BH and 0CH are the 16-bit CRC over the length byte, Project ID and node address value. The least significant byte of the CRC is stored at address 0B. This CRC is generated according to the standardized CRC16 polynomial function X16 + X15 + X2 + 1. For more details on generating CRC values including examples in both hardware and software, see Application Note 27. The contents of the memory address range 0DH to 1FH is FFH. These cells cannot be altered since the whole memory page is write-protected. The memory range from 20H to 7FH, however, is userprogrammable. It can be write-protected by programming the corresponding write-protect bit in the status memory of the DS2502-E48.
2 of 2

▲Up To Search▲

Price & Availability of DS2502-E48

	To Download DS2502-E48 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .