DS1992_11 MAXIM [Maxim Integrated Products], DS1992_11 Datasheet
DS1992_11
Related parts for DS1992_11
DS1992_11 Summary of contents
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SPECIAL FEATURES 4096 bits of Read/Write Nonvolatile Memory (DS1993) 1024 bits of Read/Write Nonvolatile Memory (DS1992) 256-bit Scratchpad Ensures Integrity of Data Transfer Memory Partitioned into 256-bit Pages for Packetizing Data Data Integrity Assured with ...
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DESCRIPTION The DS1992/DS1993 memory iButtons (hereafter referred to as DS199x) are rugged read/write data carriers that act as a localized database, easily accessible with minimal hardware. The nonvolatile memory and optional timekeeping capability offer a simple solution to storing ...
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Figure 1. DS1992/DS1993 BLOCK DIAGRAM 1-WIRE FUNCTION 1-W PORT CONTROL MEMORY FUNCTION CONTROL 3V LITHIUM Figure 2. 64-BIT LASERED ROM MSB 8-Bit CRC Code MSB LSB Figure 3. 1-Wire CRC CODE STAGE STAGE STAGE ...
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Figure 4a. DS1993 MEMORY MAP SCRATCHPAD PAGE PAGE 0 PAGE 1 PAGE 2 PAGE 3 PAGE 4 PAGE 5 PAGE 6 PAGE 7 PAGE 8 MEMORY PAGE 9 PAGE 10 PAGE 11 PAGE 12 PAGE 13 PAGE 14 PAGE 15 ...
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MEMORY The memory map in Figure 4 shows a 32-Byte page called the scratchpad, and additional 32-Byte pages called memory. The DS1992 contains pages 0 though 3 that make up the 1024-bit SRAM. The DS1993 contain pages 0 through 15 ...
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Copy Scratchpad [55h] This command is used to copy data from the scratchpad to memory. After issuing the copy scratchpad command, the user must provide a 3-byte authorization pattern. This pattern must exactly match the data contained in the three ...
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Figure 6. MEMORY FUNCTIONS FLOW CHART Master TX Memory Function Command 0FH Write Scratchpad Bus Master TX TA1 (T7:T0) Bus Master TX TA2 (T15:T8) DS199x sets Scratchpad Offset = (T4:T0) and Clears (PF, OF, AA) Master TX Data Byte To ...
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Figure 6. MEMORY FUNCTIONS FLOW CHART (continued) From Figure 6 55H Copy Scratchpad First Part ? Y Bus Master TX TA1 (T7:T0) Bus Master TX TA2 (T15:T8) Bus Master TX E/S Byte Authorization Code Match ? ...
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MEMORY FUNCTION EXAMPLES Example: Write two data Bytes to memory locations 0026h and 0027h (the seventh and eighth Bytes of page 1). Read entire memory. MASTER MODE DATA (LSB FIRST ...
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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 DS199x is a slave device. The bus master is typically a microcontroller or PC. For small ...
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The presence pulse lets the bus master know that the DS199x is on the bus and is ready to operate. For more details, see the 1-Wire Signaling section. ROM FUNCTION COMMANDS Once the bus master has detected a presence, ...
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Figure 9. ROM FUNCTIONS FLOW CHART 33H N Read ROM Match ROM Command Command ? Y DS199x TX Family Code Master TX Bit 0 1 Byte Match ? DS199x TX Master TX Bit 1 Serial Number 6 Bytes Match ? ...
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Figure 10. INITIALIZATION PROCEDURE RESET AND PRESENCE PULSE MASTER TX "RESET PULSE" V PULLUP V PULLUP MIN V IH MIN V IL MAX 0V t RSTL RESISTOR MASTER DS199x READ/WRITE TIME SLOTS The definitions of write and read time slots ...
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Figure 11. READ/WRITE TIMING DIAGRAM (continued) Write-Zero Time Slot V PULLUP V PULLUP MIN V IH MIN V IL MAX 0V RESISTOR MASTER Read-Data Time Slot V PULLUP V PULLUP MIN V IH MIN V IL MAX 0V RESISTOR MASTER ...
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PHYSICAL SPECIFICATIONS Size Weight Expected Service Life Safety ABSOLUTE MAXIMUM RATINGS Voltage Range on any Pin Relative to Ground Operating Temperature Range Storage Temperature Range This is a stress rating only and functional operation of the device at these or ...
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Note 1: All voltages are referenced to ground. Note function of the external pullup resistor and the V IH Note external pullup voltage. PUP Note 4: Input load is to ground. Note 5: ...
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REVISION HISTORY REVISION DATE 7/08 Updated the F5 MicroCan face brand with the latest per PCN H020201. Change the last sentence of the Parasite Power section to “The advantages of parasite power are two-fold parasiting off this input, ...