DS2251T_06 DALLAS [Dallas Semiconductor], DS2251T_06 Datasheet
DS2251T_06
Related parts for DS2251T_06
DS2251T_06 Summary of contents
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FEATURES 8051-Compatible Microcontroller Adapts to Its Task 32, 64, or 128kbytes of Nonvolatile SRAM for Program and/or Data Storage In-System Programming via On-Chip Serial Port Capable of Modifying its Own Program or Data Memory in the End System Provides ...
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The DS2251T provides the benefits of NV RAM without using I/O resources. Between 32 kbytes and 128 kbytes of onboard NV RAM are available. A non-multiplexed Byte-wide address and data bus is used for memory access. This bus, which is ...
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DS2251T BLOCK DIAGRAM Figure ...
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PIN ASSIGNMENT PIN NAME PIN 1 P1.0 2 P1.1 3 P1.2 4 P1.3 5 P1.4 6 P1.5 7 P1.6 8 P1.7 9 RST 10 P3.0/RXD 11 P3.1/TXD 12 P3.2/ INT0 13 P3.3/ INT1 14 P3.4/T0 15 P3.5/T1 16 P3.6/ WR ...
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PIN 15 P3.5/T1. General-purpose I/O port pin 3.5. Also serves as the Timer 1 input. P3.6/ . General-purpose I/O port pin. Also serves as the write strobe for Expanded bus WR 16 operation. P3.7/ . General-purpose I/O port pin. Also ...
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PIN . This I/O pin (open-drain with internal pullup) indicates that the power supply (V VRST has fallen below the V 71 DS2251T will drive this pin to a logic 0. Because the micro is lithium backed, this signal is ...
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DS2251T MEMORY MAP IN NON-PARTITIONABLE MODE ( Figure 2 DS2251T MEMORY MAP IN PARTITIONABLE MODE ( Figure ...
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DS2251T MEMORY MAP WITH (PES = 1) Figure 4 POWER MANAGEMENT The DS2251T monitors V CC switchover to lithium backup. It uses an internal band-gap reference in determining the switch points. These are called PFW CCMIN perform ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground……………………………………...-0. Voltage Range on V Relative to Ground………………………………………………….-0.3V to +6.0V CC Operating Temperature Range………………………………………………………………-40°C to +85°C Storage Temperature (Note 1)……………………………………………………………..-55°C to +125°C Soldering Temperature………………………………………………………………+260°C for 10 seconds This ...
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DC CHARACTERISTICS (continued ±10 0˚C to +70˚C PARAMETER Idle Mode Current at 12MHz Stop Mode Current Pin Capacitance With BAT = 3.0V Reset Trip Point in Stop Mode With BAT = 3.3V AC ...
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AC CHARACTERISTICS—EXPANDED BUS MODE TIMING SPECIFICATIONS (continued ±10 0˚C to +70˚C PARAMETER 19 ALE Low to Valid Data In Valid Address to Valid Data ALE Low ...
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EXPANDED DATA MEMORY READ CYCLE ...
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EXPANDED DATA MEMORY WRITE CYCLE ...
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AC CHARACTERISTICS—EXTERNAL CLOCK DRIVE = 5V ±10 0˚C to +70˚C PARAMETER 28 External Clock High Time 29 External Clock Low Time 30 External Clock Rise Time 31 External Clock Fall Time EXTERNAL CLOCK TIMING ...
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AC CHARACTERISTICS—POWER CYCLE TIMING = 5V ±10 0˚C to +70˚C PARAMETER 32 Slew Rate from V CCMIN 33 Crystal Startup Time 34 Power-On Reset Delay POWER CYCLE TIMING SYMBOL to 3. ...
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AC CHARACTERISTICS—SERIAL PORT TIMING: MODE ±10 0˚C to +70˚C PARAMETER 35 Serial Port Cycle Time 36 Output Data Setup to Rising Clock Edge 37 Output Data Hold after Rising Clock Edge ...
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AC CHARACTERISTICS—PARALLEL PROGRAM LOAD TIMING = 5V ±10 0˚C to +70˚C PARAMETER 41 Pulse Width of 3-4 PE Byte-wide Address Hold after 45 During MOVX Delay from Byte-wide Address Valid 46 Low During MOVX ...
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RPC AC CHARACTERISTICS—DBB READ = 5V ±10 0˚C to +70˚C PARAMETER Setup Hold After Pulse Width ...
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RPC TIMING MODE 16 RPC TIMING MODE 16 (continued ...
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NOTES: 1. All voltages are referenced to ground. 2. Maximum operating =10ns 0.5V; XTAL2 disconnected; RST = PORT0 = V CLKF IL 3. Idle mode I is measured with all output pins disconnected; XTAL1 driven ...
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PACKAGE DRAWING PKG INCHES DIM MIN MAX A 4.245 4.255 B 3.979 3.989 C 0.995 1.005 D 0.395 0.405 E 0.245 0.255 F 0.050 BSC G 0.075 0.085 H 0.245 0.255 I 1.750 BSC J 0.120 0.130 K 2.120 2.130 ...
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DATA SHEET REVISION SUMMARY The following represent the key differences between 12/13/95 and 08/13/96 version of the DS2251T data sheet. Please review this summary carefully. 1. Change V slew rate definition to reference 3.3V instead Add ...