DS2408S Maxim Integrated Products, DS2408S Datasheet
DS2408S
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DS2408S Summary of contents
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... Addressable Switch PIN CONFIGURATION N. I/O 4 GND 5 N. 150-mil SO ORDERING INFORMATION TEMP PART RANGE DS2408S -40°C to +85°C DS2408S -40°C to +85°C /T& DS2408 16 N. RSTZ 9 P5 PACKAGE 16-Pin SO, 150 mil Tape-and-Reel of DS2408S 051403 ...
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ABSOLUTE MAXIMUM RATINGS P7, RSTZ, I/O Voltage to GND P0 to P7, RSTZ, I/O combined sink current Operating Temperature Range Junction Temperature Storage Temperature Range Lead Temperature (10s) * This is a stress rating only and functional operation ...
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PARAMETER SYMBOL I/O Pin, 1-Wire Reset, Presence-Detect Cycle Reset-Low Time t RSTL (Notes 1, 12) Presence-Detect High t PDH Time (Note 12) Presence-Detect Fall t FPD Time (Note 13) Presence-Detect Low t PDL Time (Note 12) Presence-Detect t MSP Sample ...
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Note 1: System Requirement Note 2: Maximum allowable pullup resistance is a function of the number of 1-Wire devices in the system and 1-Wire recovery times. The specified value here applies to systems with only one device and with the ...
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PIN DESCRIPTION PIN NAME 1 N. I/O 5 GND 6 N. RSTZ N.C. 16 N.C. APPLICATION The DS2408 ...
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Figure 1. DS2408 BLOCK DIAGRAM V CC I/O GND Figure 2. HIERARCHICAL STRUCTURE FOR 1-Wire PROTOCOL Bus Master Command Level: 1-Wire ROM Function Commands DS2408-Specific Control Function Commands PARASITE POWER INTERNAL V CC 1-WIRE FUNCTION CONTROL REGISTER FUNCTION CONTROL CRC16 ...
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PARASITE POWER The DS2408 can derive its power entirely from the 1-Wire bus by storing energy on an internal capacitor during periods of time when the signal line is high. During low times the device continues to operate from this ...
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Figure 5. DS2408 REGISTER ADDRESS MAP ADDRESS RANGE ACCESS TYPE 0000h to 0087h 0088h 0089h 008Ah 008Bh 008Ch 008Dh 008Eh to 008Fh PIO Logic-State Register The logic state of the PIO pins can be obtained by reading this register using ...
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PIO Activity Latch State Register The data in this register represents the current state of the PIO activity latches. This register is read using the Read PIO Registers command. Reading this register does not generate a signal at the RSTZ ...
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Conditional Search Channel Selection Mask Register The data in this register controls whether a PIO channel qualifies for participation in the conditional search command. To include one or more of the PIO channels, the bits in this register that correspond ...
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Control/Status Register The data in this register reports status information, determines the function of the RSTZ pin and further configures the device for conditional search. This register can only be written through the Write Condi- tional Search Registers command. Control/Status ...
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Figure 8-1. CONTROL FUNCTIONS FLOW CHART Bus Master TX Control Function Command Read PIO Reg.? Bus Master TX TA1 (T7:T0), TA2 (T15:T8) N Address < 90h? From ROM Functions Flow Chart (Figure 12) F0h N Note read the ...
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Figure 8-2. CONTROL FUNCTIONS FLOW CHART From Figure Part Channel Access Note 1) DS2408 Samples See the command PIO Pin Status description for the exact timing of the PIO Sample PIO pin sampling and updating. Y Sample ...
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Figure 8-3. CONTROL FUNCTIONS FLOW CHART From Figure Part Write C. Search TA1 (T7:T0), TA2 (T15:T8) Note: To read 8Bh to 8Dh use the Read PIO Registers command. N 8Bh£ Address £ Bus Master RX “1”s N ...
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CONTROL FUNCTION COMMANDS Once a ROM function command is completed, the Control Function Commands can be issued. The Control Functions Flow Chart (Figure 8) describes the protocols necessary for accessing the PIO channels and the special function registers of the ...
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The status of all eight PIO channels is sampled at the same time. The first sampling occurs during the last (most significant) bit of the command code F5h. While the master receives the MSB of the PIO status (i.e., the ...
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AAh. If the RSTZ pin is configured as transmission of the first two (least significant) bits of the confirmation byte. The strobe can signal a FIFO or a microcontroller to read the new data byte from the ...
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Figure 11. HARDWARE CONFIGURATION SIMPLE BUS MASTER RX TX OPEN-DRAIN PORT PIN DS2480B BUS MASTER HOST CPU SERIAL SERIAL IN PORT SERIAL OUT A multidrop bus consists of a 1-Wire bus with multiple slaves attached. At standard speed the 1-Wire ...
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TRANSACTION SEQUENCE The protocol for accessing the DS2408 through the 1-Wire port is as follows: § Initialization § ROM Function Command § Control Function Command § Transaction/Data Illustrations of the transaction sequence for the various control function commands are found ...
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PLS of the Control/Status Register (address 008Dh), and the state of the PIO channels. See Figure 7 for a description of the Conditional Search logic. The device also responds to the Conditional Search if the PORL bit is set. The ...
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Figure 12-1. ROM FUNCTIONS FLOW CHART From Control Functions Flow Chart (Figure 8) Bus Master TX ROM Function Command 33h N Read ROM Command DS2408 TX Master TX Bit 0 Family Code (1 Byte) DS2408 TX ...
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Figure 12-2. ROM FUNCTIONS FLOW CHART st To Figure 12, 1 Part From Figure Part CCh N Skip ROM Command From Figure Part To Figure Part A5h ...
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SIGNALING The DS2408 requires strict protocols to ensure data integrity. The protocol consists of four types of signaling on one line: Reset Sequence with Reset Pulse and Presence Pulse, Write-Zero, Write-One, and Read-Data. Except for the presence pulse, the ...
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Read/Write Time Slots Data communication with the DS2408 takes place in time slots, which carry a single bit each. Write time slots transport data from bus master to slave. Read time slots transfer data from slave to master. The definitions ...
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Read-Data Time Slot PUP V IHMASTER ILMAX RESISTOR Slave-to-Master A read-data time slot begins like a write-one time slot. The voltage on the data line must remain below V ...
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The input buffer was designed with hysteresis negative glitch crosses will not be recognized (Figure 15, Case A). The hysteresis is effective at any 1-Wire TH HY speed. 4) There is ...
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Figure 16. CRC-16 HARDWARE DESCRIPTION AND POLYNOMIAL STAGE STAGE STAGE STAGE STAGE Figure 17. DS2408 AS SLAVE INTERFACE FOR MICROCONTROLLER ...
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Figure 18. DS2408 AS SLAVE INTERFACE FOR INTELLIGENT DISPLAY VCC 5VDC GND 1W Figure 19. DS2408 AS MICROCONTROLLER PORT EXPANDER MICROCONTROLLER WITH FEW I/O PINS VCC 1 VCC GND 2 OSC1/ OSC2/ CLR/P3 P2/CK PIC12C508 24 ...
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Figure 20. DS2408 AS µC-OPERATED KEYBOARD SCANNER VCC VCC GND Figure 21. DS2408 AS PARASITE-POWERED PUSH-BUTTON SENSOR VCC 0.1U Parasite Power 1W GND 10U VCC ...
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Figure 22. DS2408 AS MULTIPURPOSE SENSOR/ACTUATOR 47U VCC VCC 1W 3 GND VCC GND DS2408 10kW ...
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Command-Specific 1-Wire Communication Protocol—Legend SYMBOL RST 1-Wire Reset Pulse generated by master. PD 1-Wire Presence Pulse generated by slave. Select Command and data to satisfy the ROM function protocol. RPR Command "Read PIO Registers". CAR Command "Channel-Access Read". CAW Command ...
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... Figure 17. They show how to write to the PIO with readback for verification or for receiving an immediate response (example 1) and how to read from the PIO in an endless loop (example 2). The third example assumes a network of multiple DS2408s where each of the devices is connected to 8 pushbuttons Figure 21. ...
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MASTER MODE TX RX Step Step (—) RX (— (— When using this communication example to send data to a ...
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MASTER MODE Step Step (—) RX (—) RX (— When using this communication example to read data from a remote microcontroller Figure ...
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Control/Status register, Source is Activity Latch Þ PLS = 1 Term is OR Þ RSTZ = inactive (input) Þ ROS = 0 Clear Power-On Reset Latch Þ PORL = 0 The resulting setup data for the Control/Status ...
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... After all DS2408s are initialized, perform the search process below as an endless loop: MASTER MODE Step Step (— (—) Note 1: For a full description of the Search Algorithm see Application Note 187. DATA (LSB FIRST) ...