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DS21T09 Plug and Play SCSI Terminator
FEATURES
Fully compliant with SCSI-1, Fast SCSI and Ultra SCSI C...
www.dalsemi.com
DS21T09 Plug and Play SCSI Terminator
FEATURES
Fully compliant with SCSI-1, Fast SCSI and Ultra SCSI Compatible with Plug and Play SCSI Profile Functional drop in replacement for the DS2109 Complementary part to DS21T07 for wide SCSI Provides active termination for 18 signal lines 2% tolerance on termination resistors and voltage
regulator Bus termination sensing Low power-down capacitance of 3 pF Onboard thermal shutdown circuitry
PIN ASSIGNMENT
PDI 1
28 GND
R1 2 R2 3 R3 4
R4 5 R5 6
27 R18
26 R17 25 R16 24 R15 23 R14
HS-GND HS-GND
PDO R6 R7 R8 R9
TPWR
7 8 9 10 11 12 13 14
22 TCS 21 HS-GND 20 PDE 19 R13 18 R12 17 R11 16 R10 15 VREF
DS21T09S 28-Pin SOIC (300-mil)
DESCRIPTION
The DS21T09 is intended for one-chip Plug and Play (
PnP) SCSI termination. Plug and Play SCSI requires the exit-point terminator on computer motherboards or host bus adapters to automatically switch off if an external device is connected to the system. The DS21T09 satisfies this requireme...