A power efficient and reduced electromagnetic interference (EMI) emissions transmitter
for unshielded twisted pair (UTP) data communication applications. Transmit data
is interpolated by N and processed by a digital filter to obtain the pulse shape
required by the particular communication application. The digital filter output
data is converted to a current-mode analog waveform by a digital-to-analog converter
(DAC). The digital filter is integrated with the DAC binary decoder in a memory
device such as a ROM with time multiplexed output. When implemented in such manner,
the logical implementation and memory replaces digital filtering circuits, DAC
decoding logic circuit and re-synchronization logic circuits that are conventionally
implemented in hardware. Thus, the hardware functionality of these circuits is
rendered into arithmetic form and implemented in a memory device.