DS2480B+ Maxim Integrated Products, DS2480B+ Datasheet
DS2480B+
Specifications of DS2480B+
Related parts for DS2480B+
DS2480B+ Summary of contents
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... Programming Voltage POL - RXD/TXD Polarity Select TXD - Serial Data from UART RXD - Serial Data to UART ORDERING INFORMATION TEMP PART RANGE DS2480B+ -40°C to +85°C DS2480B+T&R -40°C to +85°C + Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel DS2480B Driver 8 RXD 7 TXD 6 POL ...
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DS2480B uses a unique protocol that merges data and control information without requiring control pins. This approach maintains compatibility to off-the-shelf serial to wireless converters, allowing easy realization of 1-Wire media jumpers. The various control functions of the DS2480B are ...
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As data enters the core of the DS2480B’s logic circuitry analyzed to separate data and command bytes and to calibrate the device’s timing generator. The timing generator controls all speed relations of the communication interface and the 1-Wire ...
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Figure 2. STATE TRANSITION DIAGRAM LEGEND: V BINARY VALUE (TYPE OF WRITE TIME SLOT) SS 1-WIRE SPEED SELECTION CODE P IF LOGIC 1, GENERATES STRONG PULLUP TO 5V IMMEDIATELY TIME SLOT T TYPE OF PULSE STRONG PULLUP (5V), ...
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A master reset cycle can also be generated by means of software. This may be necessary if the host for any reason has lost synchronization with the device. The DS2480B will perform a master reset cycle equivalent to the power-on ...
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In addition to the command codes explained in the subsequent sections the DS2480B understands the following reserved command codes: E1h switch to Data Mode E3h switch to Command Mode F1h pulse termination Except for these reserved commands, the Search Accelerator ...
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Table 1. COMMUNICATION COMMAND CODES FUNCTION BIT 7 BIT 6 Single Bit 1 Search Accelerator 1 Control Reset 1 Pulse 1 Table 2. COMMUNICATION COMMAND RESPONSE FUNCTION BIT 7 BIT 6 Single Bit 1 0 Reset 1 1 Pulse 1 ...
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Data Mode. The arm/disarm function is controlled by bit 1 of the command code. Bit 4 determines whether the device will generate a strong ...
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During the execution of the Search ROM function, the Search Accelerator receives from the host information on the preferred path to choose as one contiguous chain of bytes and then translates it into the appropriate time slots on the 1-Wire ...
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The type of time slot b2 (write 1 or write 0) is determined by the DS2480B as follows conflict (as chosen by the host conflict (there is no alternative ...
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Search Accelerator Usage Example Action Sequence Generate Reset Pulse Set Data Mode Search ROM command Set Command Mode Search Accelerator On Set Data Mode Send 16 bytes Set Command Mode Search Accelerator Off Set Data Mode Do Memory Function Set ...
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Table 3. CONFIGURATION PARAMETER OVERVIEW Parameter Description Par. Code Pulldown Slew Rate Control Programming Pulse Duration Strong Pullup Duration Write-1 Low Time Data Sample Offset and Write 0 Recovery Time RS232 Baud Rate The numbers given for parameter 001 (Pulldown ...
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Table 4. CONFIGURATION PARAMETER VALUE CODES Parameter Code 000 001 (PDSRC) 15 010 (PPD) 32 011 (SPUD) 16.4 100 (W1LT) 8 101 (DSO/W0RT) 3 110 (LOAD) 1.8 111 (RBR) 9.6 Note: The value code 110 of parameter 011 (Strong Pullup ...
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CONTROLLED EDGES One of the tasks of the DS2480B is to actively shape the edges of the 1-Wire communication waveforms. This speeds up the recharging of the 1-Wire bus (rising edges) and reduces ringing of long lines (falling edges). The ...
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Falling Edges (DS2480B-initiated) Whenever the DS2480B begins pulling the 1-Wire bus low to initiate a time slot, for example, it first turns off the weak pullup current I falling edge at a slew rate of typically 15V/s. This value is ...
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COMMUNICATION WAVEFORMS One of the major features of the DS2480B is that it relieves the host from generating the timing of the 1-Wire signals and sampling the 1-Wire bus at the appropriate times. How this is done for the ...
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A Write-1 and Read Data time slot is comprised of the segments t time slots, after the Write-1 low time t offset and then samples the voltage at the 1-Wire bus to read the response. After this, the waiting time ...
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PULSE WAVEFORMS, DISARMED The Pulse command can be used to generate a strong pullup to 5V and a 12V programming pulse, respectively. The duration of the pulse is predefined if the parameter value code of parameter 010 (Programming Pulse Duration) ...
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For EPROM programming, only a single slave device should be connected to the 1-Wire bus and the cable must to be short, not to exceed a few meters. One should not attempt generating a programming pulse with a non-EPROM device ...
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PULSE WAVEFORM, ARMED As explained in the Communication Commands section, bit 1 of the Pulse command allows the arming of a strong pullup the bit is set the strong pullup is armed and the ...
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SINGLE BIT WITH STRONG PULLUP Similar to the Pulse command, the Single Bit command also allows generating a strong pullup immediately following a time slot. The strong pullup of the Single Bit command, however, is controlled directly by bit 1 ...
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The minimum duration of a strong pullup of infinite duration strongly depends on the baud rate of the communication between host and DS2480B. The host must first receive the response byte of the Single Bit command, react to it and ...
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READ MEMORY SEQUENCE Action Sequence Generate Reset Pulse Set Data Mode Skip ROM Command Read Memory Command Starting Address TA1 Starting Address TA2 Read 8 Bytes of Data Set Command Mode Generate Reset Pulse WRITE EPROM SEQUENCE (DS2505) Write memory ...
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HARDWARE APPLICATION EXAMPLES This section discusses five typical application scenarios. The DS2480B can be configured for EPROM programming as well as for 5V operation only. OUTPUT FILTERING As described in the CONTROLLED EDGES section, the DS2480B employs an active pullup ...
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Figure 11a. UART DIRECT 12 V Regulator UART SIN (RXD) or μC SOUT (TXD Start 0 Figure 11b. ±5V RS232 DTR RTS UART SIN (RXD) or μC SOUT (TXD Start 0 The signals DTR and RTS ...
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Figure 11c. ±12V RS232 DTR RTS SIN UART (RXD) or μC SOUT (TXD) 1 μ Start 0 In the interface to a true RS232C system (12V, Figure 11c) the power for the DS2480B is stolen from DTR and ...
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Figure 11d. UART DIRECT OPTO-ISOLATED 5 V SIN (RXD) UART or μC SOUT (TXD) L Start The circuit in Figure 11d is essentially the same as in Figure 11a. The main difference is the opto- isolation. The characteristics of the ...
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Figure 12. RS232 DATA TIMING RXD LINE Figure 13. RECEIVE DELAY TIMING Figure 14. RS232 DATA TIMING TXD LINE Figure 15. TXD LINE ASYMMETRY ...
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Table 7. FUNCTION AND SPEED MATRIX Baud Rate 9600bps 19200bps 57600bps 115200bps √ guaranteed by the UART; no precautions necessary. IDLET X Not recommended unless t 1-Wire Speed Standard Flexible √ √ √ √ √ X ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on 1-W to Ground Voltage on VPP to Ground Voltage on VDD, RXD, TXD, POL to Ground Operating Temperature Range Storage Temperature Range Lead Temperature (soldering, 10s) Soldering Temperature (reflow) * This is a stress rating ...
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AC ELECTRICAL CHARACTERISTICS PARAMETER UART Bit Time Device Bit Time Fall Time RXD Rise Time RXD Transmit Idle Time Receive Idle Time Asymmetry Arrival Response Time Master Reset Time Active Pullup on Time Response Time NOTES: - ...
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... Maxim/Dallas Semiconductor cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim/Dallas Semiconductor product. No circuit patent licenses are implied. Maxim/Dallas Semiconductor reserves the right to change the circuitry and The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas DESCRIPTION spec, changed V PPmin from 5 ...