DS2703U+ Maxim Integrated Products, DS2703U+ Datasheet
DS2703U+
Specifications of DS2703U+
Related parts for DS2703U+
DS2703U+ Summary of contents
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... Handheld or Notebook Computers and Terminals Digital Still and Video Cameras PART TEMP RANGE -20°C to +70°C 2mm x 3mm TDFN DS2703G+ on -20°C to +70°C Tape-and-Reel μMAX-8 -20°C to +70°C DS2703U+ on -20°C to +70°C Tape-and-Reel DS2703 ® Interface PIN-PACKAGE REV: 061307 ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on DQ, THM Pins Relative to Ground Voltage Range on VB Pin Relative to Ground Operating Temperature Range Storage Temperature Range Soldering Temperature Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage ...
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AC ELECTRICAL CHARACTERISTICS (V = 2.7V to 5.5V -20°C to +70°C.) PULLUP A PARAMETER THM Low Delay Computation Delay Time Computation Time Programming Pulse Width Programming Pulse Rise Time Programming Pulse Fall Time Start-up Delay Time AC ELECTRICAL ...
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PIN DESCRIPTION 8-PIN 2mm x 3mm NAME µMAX TDFN 1 7 THM N.C. Figure 1. Block Diagram Thermistor Mux. ...
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DETAILED DESCRIPTION The DS2703 is comprised of a SHA-1 Authentication function and thermistor mux control that are accessed via a 1- Wire interface. The high voltage (HV) detection circuit routes the externally supplied programming voltage to the EEPROM array and ...
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Table 1. Variable Initiation [31:0] A 67h B EFh 98h C D 10h E C3h The 160-bit MAC is computed per FIPS 180, including the addition of constants H0-H4. Adding H0-H4 is necessary only to maintain compliance with FIPS 180. ...
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SHA Computation The variables and constants H0, H1, H2, H3, and H4 are initialized as follows 67452301h B := EFCDAB89h C := 98BADCFEh D := 10325476h E := C3D2E1F0h The final values of ...
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SHA-1 related commands used while authenticating a battery or peripheral device are summarized in Table 3 for convenience. Four additional commands for clearing, computing and locking of the Secret are described in detail in the following section. Table 3. Authentication ...
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SET OVERDRIVE [8Bh]. This command sets the 1-Wire Overdrive bit to select the Overdrive 1-Wire timings shown in the Electrical Characteristics table. The Overdrive bit is stored in EEPROM so that the programmed speed selection can be recalled on initial ...
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The DS2703 will remain in thermistor measurement mode until the stored charge on the VB pin capacitor is depleted causing the IC to power cycle back to standard mode of operation. While in thermistor measurement mode, communication to the DS2703 ...
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Figure 4. 1-Wire CRC Generation Block Diagram MSb HARDWARE CONFIGURATION The DS2703 uses an open-drain output driver as part of the bidirectional interface circuitry shown in Figure bidirectional pin is not available on the bus master, separate ...
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TRANSACTION SEQUENCE The protocol for accessing the DS2703 through the 1-Wire port is as follows: Initialization Net Address Command Function Command(s) Data Transfer (not all commands have data transfer) All transactions of the 1-Wire bus begin with an initialization sequence ...
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Figure 6. Net Address Command Flow Chart 33h NO READ YES DS2703 Tx FAMILY CODE 1 BYTE DS2703 Tx SERIAL NUMBER 6 BYTES DS2703 Tx CRC 1 BYTE MASTER Tx YES FUNCTION COMMAND MASTER Tx RESET PULSE DS2703 Tx PRESENCE ...
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I/O SIGNALING The 1-Wire bus requires strict signaling protocols to ensure data integrity. The four protocols used by the DS2703 are as follows: the initialization sequence (reset pulse followed by presence pulse), write 0, write 1, and read data. The ...
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Figure 8. 1-Wire Write and Read Time Slots ...
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Table 7. All Function Commands COMMAND HEX Write Challenge 0C Compute MAC without ROM_ID and 36 return MAC Compute MAC 35 with ROM_ID and return MAC Load Secret 5A Compute Next Secret 30 without ROM ID Compute Next Secret 33 ...
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LOW-IMPEDANCE DQ DURING COMPUTATION The SHA-1 computation requires more current than the DQ pullup resistor used during normal communication can supply. During the computation, the DQ source impedance must be reduced to maintain power to the device under the higher ...
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PROGRAMMING PULSE A typical programming waveform is shown in Figure 10. The user issues a 1-Wire reset followed by a Skip ROMID command, Match ROMID plus the ROMID, Search or Read Net, the Load Secret command and then the two ...
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COMPUTATION AND PROGRAMMING The Compute Next Secret operation waveform is shown in Figure 11. The user issues a 1-Wire reset followed by a Skip ROMID command, Match ROMID plus the ROMID, Search or Read Net, followed by the Compute Next ...
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HIGH-IMPEDANCE DQ FOR THERMISTOR MEASUREMENT The user issues a 1-Wire reset followed by a Skip ROMID command, Match ROMID plus the ROMID, Search or Read Net, followed by the Activate Thermistor command. Within the time period t input and internally ...