ds2482-100-ds2482s-100 Maxim Integrated Products, Inc., ds2482-100-ds2482s-100 Datasheet
ds2482-100-ds2482s-100
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ds2482-100-ds2482s-100 Summary of contents
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... C masters to perform bidirectional pro- 2 tocol conversion between the I downstream 1-Wire slave devices. Relative to any attached 1-Wire slave device, the DS2482-100 is a 1-Wire master. Internal, factory-trimmed timers relieve the system host processor from generating time-critical 1-Wire waveforms, supporting both standard and over- drive 1-Wire communication speeds ...
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Single-Channel 1-Wire Master ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground.........-0.5V to +6V Maximum Current into Any Pin..........................................±20mA Operating Temperature Range ...........................-40°C to +85°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to ...
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ELECTRICAL CHARACTERISTICS (continued 2.9V to 5.5V -40°C to +85°C PARAMETER SYMBOL Fall Time High-to-Low (Notes 6, 7) Write-Zero Low Time Write-Zero Recovery Time t Reset Low Time Presence-Detect Sample Time Sampling for Short and ...
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... Note 10: Applies to SDA, SCL, AD0 and AD1. Note 11: The input/output pins of the DS2482-100 do not obstruct the SDA and SCL lines if V Note 12: The DS2482-100 provides a hold time of at least 300ns for the SDA signal (referred to the V bridge the undefined region of the falling edge of SCL. ...
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... Figure 1. Block Diagram _______________________________________________________________________________________ Single-Channel 1-Wire Master FUNCTION CC or GND. These inputs determine the I CC CONFIGURATION T-TIME OSC REGISTER INPUT/OUTPUT CONTROLLER INTERFACE CONTROLLER STATUS REGISTER DS2482-100 READ DATA REGISTER Pin Description through a pullup resistor. through a pullup resistor slave LINE IO XCVR PCTLZ 5 ...
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... Single-Channel 1-Wire Master Detailed Description The DS2482-100 is a self-timed 1-Wire master that sup- ports advanced 1-Wire waveform features including standard and overdrive speeds, active pullup, strong pullup for power delivery, and presence-pulse masking. The active pullup affects rising edges on the 1-Wire side ...
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... Reflections can cause glitches in the network that, in turn, can cause slave devices to lose synchronization with the 1-Wire master. Figure 3 shows the timing references for the presence- pulse masking. If enabled (PPM = 1), the DS2482-100 begins pulling the 1-Wire line low at t reset low time t t ...
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... Electrical Characteristics to determine if the internal strong pullup is sufficient given the current load on the device. If SPU is 1, the DS2482-100 treats the rising edge of the time slot in which the strong pullup starts as if the active pullup was activated. However, in contrast to the active pullup, the strong pullup, i.e., the internal pullup transis- ...
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... DS2482-100 in read mode (during the acknowledge cycle), provided that the read pointer is positioned at the Status Register. If the RST bit is 1, the DS2482-100 has performed an internal reset cycle, either caused by a power-on reset 1-Wire Busy (1WB) or from executing the Device Reset command. The RST ...
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... Single-Channel 1-Wire Master Function Commands The DS2482-100 understands eight function com- mands that fall into four categories: device control, I communication, 1-Wire setup, and 1-Wire communica- tion. The feedback path to the host is controlled by a read pointer, which is set automatically by each func- tion command for the host to efficiently access relevant information ...
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... Status Register, bits PPD and SD. Typical Use To initiate or end any 1-Wire communication sequence. Restriction 1-Wire activity must have ended before the DS2482-100 can process this command. Command code is not acknowledged if 1WB = 1 at the time the command code is received and Error Response the command is ignored. ...
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... To perform single-bit writes or reads at the 1-Wire line when single bit communication is Typical Use necessary (the exception). Restriction 1-Wire activity must have ended before the DS2482-100 can process this command. Command code and bit byte are not acknowledged if 1WB = 1 at the time the command code is Error Response received and the command is ignored. ...
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... F1 PULLUP (SEE FIGURE 2) NOTE: DEPENDING ON ITS INTERNAL STATE, A 1-Wire SLAVE DEVICE TRANSMITS DATA TO ITS MASTER (e.g. THE DS2482-100). WHEN RESPONDING WITH 1-Wire SLAVE STARTS PULLING THE LINE LOW DURING t STARTS RISING AGAIN. WHEN RESPONDING WITH 1-Wire SLAVE DOES NOT HOLD THE LINE LOW AT ALL, AND THE VOLTAGE STARTS RISING AS SOON OVER ...
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... Begins maximum 262.5ns after the falling SCL edge of the command code acknowledge bit. Status Register (for busy polling). Note: To read the data byte received from the 1-Wire line, issue Read Pointer Position the Set Read Pointer command and select the Read Data Register. Then access the DS2482-100 in read mode. Status Bits Affected ...
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... The direction byte determines the type of write time slot if both read time slots are 0 (a typical case). In this case, the DS2482-100 generates a write-one time slot and a write-zero time slot Description See Table 3 ...
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... Interface transmitted first. After each byte follows an acknowledge bit to allow synchronization between master and slave. The slave address to which the DS2482-100 responds is shown in Figure 9. The logic state at the address pins AD0 and AD1 determines the value of the address bits A0 and A1. The address pins allow the device to respond to one of four possible slave addresses ...
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SDA t BUF t LOW SCL t t HD:STA R STOP START NOTE: TIMING IS REFERENCED TO V AND V . IL(MAX) IH(MIN) 2 Figure 10 Timing Diagram The following terminology is commonly used to 2 describe I ...
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... Reading from the DS2482-100 To read from the DS2482-100, the master must access the device in read mode, i.e., the slave address must be sent with the direction bit set to 1. The read pointer determines the register that the master reads from. The ...
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... In the first cycle, the master sends the command. Then the master waits (Idle) for the 1-Wire reset to complete. In the second cycle, the DS2482-100 is accessed to read the result of the 1-Wire reset from the Status Register. Case B: 1-Wire Idle (1WB = 0), Busy Polling Until the 1-Wire Command is Completed, then Read the Result ...
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... When 1WB has changed from the 1-Wire Write Byte command is completed. Case C: 1-Wire Busy (1WB = 1) S AD,0 A 1WWB A\ The master should stop and restart as soon as the DS2482-100 does not acknowledge the command code. 20 ______________________________________________________________________________________ Communication Examples (continued) <byte> (Idle) ...
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... Register (code E1h) and access the device again to read the data byte that was obtained from the 1-Wire line. Case D: 1-Wire Busy (1WB = 1) S AD,0 A 1WRB A\ The master should stop and restart as soon as the DS2482-100 does not acknowledge the command code. ______________________________________________________________________________________ Single-Channel 1-Wire Master Communication Examples (continued) P (Idle) SRP ...
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... S AD,0 A 1WT A\ The master should stop and restart as soon as the DS2482-100 does not acknowledge the command code. Applications Information SDA and SCL Pullup Resistors SDA is an open-drain output on the DS2482-100 that requires a pullup resistor to realize high-logic levels. Because the DS2482-100 uses SCL only as input (no ...
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... R CURRENT-LIMITING RESISTOR SDA SCL PCTLZ DS2482-100 1-Wire LINE AD0 IO AD1 V CC SDA SCL PCTLZ DS2482-100 1-Wire LINE V AD0 IO CC AD1 SIZING MAX LOAD AT MIN PULLUP VOLTAGE (V) ” line 1-Wire DEVICE #1 (WITH SPECIAL POWER ...
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... TOP VIEW (BUMP SIDE DOWN) DS2482-100 PCTLZ AD1 AD0 B SCL SDA GND IO WLP PACKAGE CODE — W92A1+1 Pin Configurations TOP MARK DS2482-100 WLP Package Information DOCUMENT NO. 56-G2008-001 21-0067 ...
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... Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 25 © 2008 Maxim Integrated Products Single-Channel 1-Wire Master DESCRIPTION and R values in the Electrical Characteristics table. IL1 WPU is a registered trademark of Maxim Integrated Products, Inc. Revision History PAGES CHANGED ...