IMP5245

The IMP5245/5246 ICs are Low Voltage Differential (LVD) terminators designed to comply with the LVD termination specification in the SPI-2 document. The IMP5245/5246 are designed specifically for LVD applications.Because the IMP5245/5246 support only LVD, they have lower output capacitance than multimode terminators.

The IMP5245/5246 deliver the ultimate in SCSI bus performance while saving component cost and board area. Elimination of the external capacitors also mitigates the need for a lengthy capacitor selection process. The individual high bandwidth drivers also maximize channel separation and reduces channel-to-channel noise and cross talk. The high-bandwidth architecture insures ULTRA-2 performance, while providing  a clear migration path to ULTRA-3 and beyond.

When the IMP5245/5246 are enabled, the differential sense (DIFFSENSE) pin supplies a voltage between 1.2V and 1.4V. The terminator DIFFSENSE output is connected to the system DIFFSENSE line. If there are no single ended or HVD devices attached to the system the LVD output will be enabled. If the DIFFSENSE line is LOW, indicating a single ended device, the IMP5245/5246 output will be in a highimpedance state. If the DIFFSENSE line is HIGH, indicating a high voltage differential device, the IMP5245/5246 output will also be in a high-impedance state.

The IMP5245/5246 ICs have a TTL compatible disconnect pin. The IMP5245 is active LOW and the IMP5246 is active HIGH. During sleep mode, power supply current is reduced to just 5A. During sleep mode all outputs are in a high-impedance state. Also during sleep mode, the DIFFSENSE function is disabled and is placed in a highimpedance state.