UCC5619

UCC5619 provides 27 lines of active termination for a SCSI (Small Computer Systems Interface) parallel bus. The SCSI standard recommends active termination at both ends of the cable.

The UCC5619 is ideal for high performance 5V SCSI systems. During disconnectthe supply current is typically only 100mA, which makes the IC attractive for lower powered systems.

The UCC5619 is designed with a low channel capacitance of 2.5pF, which eliminates effects on signal integrity from disconnected terminators at interim points on the bus.

The power amplifier output stage allows the UCC5619 to source full termination current and sink active negation current when all termination lines are actively negated.

The UCC5619, as with all Unitrode terminators, is completely hot pluggable and appears as high impedance at the teminating channels with VTRMPWR = 0V or open.

Internal circuit trimming is utilized, first to trim the 110W impedance, and then most importantly, to trim the output current as close to the maximum SCSI-3 specification as possible, which maximizes noise margin in fast SCSI operation.

Other features include thermal shutdown and current limit. This device is offered in low thermal resistance versions of the industry standard 36 pin wide body QSSOP (MWP) and 48 pin LQFP (FQP).

Consult SSOP-36 (MWP QSSOP-36) and FQP-48 Packaging Diagram for exact dimensions.