TL2218-285Y

ą TL2218Ć285, TL2218Ć285Y EXCALIBUR CURRENTĆMODE SCSI TERMINATOR ą SLVS072C − DECEMBER 1992 − REVISED OCTOBER 1995 available features Fully Integrated 9-Channel SCSI Termination No External Components Required Maximum Allowed Current Applied at First High-Level Step 6-pF Typical Power-Down Output Capacitance Wide Vterm† (Termination Voltage) Operating Range, 3.5 V to 5.5 V TTL-Compatible Disable Feature Compatible With Active Negation Thermal Regulation PW PACKAGE (TOP VIEW) TERMPWR NC NC D0 D1 D2 D3 D4 NC GND 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 NC − No internal connection TERMPWR DISABLE NC D8 D7 NC D6 D5 NC GND description The TL2218-285 is a current-mode 9-channel monolithic terminator specially designed for single-ended small-computer-systems-interface (SCSI) bus termination. A user-controlled disable function is provided to reduce standby power. No impedance-matching resistors or other external components are required for its operation as a complete terminator. The device operates over a wide termination-voltage (Vterm†) range of 3.5 V to 5.5 V, offering an extra 0.5 V of operating range when compared to the minimum termination voltage of 4 V required by other integrated active terminators. The TL2218-285 functions as a current-sourcing terminator and supplies a constant output current of 23 mA into each asserted line. When a line is deasserted, the device senses the rising voltage level and begins to function as a voltage source, ...