VSC3144

The fully nonblocking switch core of the VSC3144 device is programmed using a multimode port interface that allows random access programming of each I/O port. Each VSC3144 data output can be programmed to connect to any of its inputs. The signal path through the device uses no registers and is fully asynchronous. This means there are no restrictions on the phase, frequency, or signal pattern of any input.

A high degree of signal integrity is maintained throughout the VSC3144 device because each high-speed output is a fully differential, switched-current driver with on-die terminations. Data inputs are terminated on-die using 100 resistors between true and complement inputs, with a common connection to an internal bias source, which facilitates AC coupling to the switch inputs.

Core programming for the VSC3144 device can be sequential on a port-by-port basis, or multiple program assignments can be queued and issued simultaneously using the CONFIG bit. The entire device can be initialized for straight-through, multicast, or other configurations. Unused channels can be powered down to allow efficient use of the switch in applications that require only a subset of the available I/O channels. Power-down is enabled in the software by programming individual unused outputs with a power-down code.