DS21T09S Dallas Semiconducotr, DS21T09S Datasheet
DS21T09S
Related parts for DS21T09S
DS21T09S Summary of contents
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... Plug and Play SCSI Terminator PIN ASSIGNMENT PDI HS-GND 8 HS-GND 9 PDO TPWR DS21T09S 28-Pin SOIC (300-mil DS21T09 28 GND 27 R18 26 R17 25 R16 24 R15 23 R14 22 TCS 21 HS-GND 20 PDE 19 R13 18 R12 17 R11 16 R10 15 ...
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PnP SCSI Specification PnP ISA Specification PnP BIOS Specification PnP Option ROM Specification Available from: Plug and Play forum on CompuServe (Go plugplay). FUNCTIONAL DESCRIPTION The DS21T09 is designed single chip termination subsystem for use in PnP ...
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The DS21T09 consists of three major functional blocks, Figure 2: Voltage reference, terminating resistors, and isolation switches Bus current sensing circuitry Bus ground sensing circuitry When the Bus Ground Sensing Circuitry or Bus Current Sensing Circuitry determines that the SCSI ...
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DETAILED PIN DESCRIPTION Table 1 PIN SYMBOL FCN 1 I PDI 2-6, R1…R13 T 10-13, R15…R18 16-19, 24- HS-GND PDO 14 TPWR REF 20 I PDE 22 TCS I 23 ...
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BUS GROUND SENSING If internal and external SCSI devices are connected to the SCSI bus, the DS21T09 will disconnect from the SCSI bus according to the circuit in Figure 3. To utilize this automatic disconnect method of bus sensing, configure ...
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BUS CURRENT SENSING The DS21T09 has the capability to use current sensing to determine if the SCSI bus is over- or under- terminated =resistor in series with the SCSI bus (preferable the RST line) is used to monitor ...
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BUS CURRENT SENSE CONFIGURATION Figure 6 BUS CURRENT SENSE TIMING DIAGRAM Figure ...
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DISCONNECT MODES Table 2 PDI PDE NOTE: “1” denotes pin left open circuited. WIDE SCSI CONFIGURATION Figure 8 I > 32 mA? DS21T09 ISOLATED ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the ...
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NOTES TCS PDI PDE 2. 4.00V < TERMPWR < 5.50V. 3. 0.0V < signal lines < TERMPWR. 4. All signal lines = 0.0V. 5. All signal lines open. 6. Power down enabled. 7. Guaranteed by design; not ...