The Intersil HSP45102 is Numerically Controlled Oscillator
(NCO12) with 32-bit frequency resolution and 12-bit output.
With over 69dB of spurious free dynamic range and worst
case frequency resolution of 0.009Hz, the NCO12 provides
significant accuracy for frequency synthesis solutions at a
competitive price.
The frequency to be generated is selected from two frequency
control words. A single control pin selects which word is used
to determine the output frequency. Switching from one
frequency to another occurs in one clock cycle, with a 6 clock
pipeline delay from the time that the new control word is
loaded until t4-he new frequency appears on the output.
Two pins, P0-1, are provided for phase modulation. They are
encoded and added to the top two bits of the phase
accumulator to offset the phase in 90° increments.
The 13-bit output of the Phase Offset Adder is mapped to the
sine wave amplitude via the Sine ROM. The output data
format is offset binary to simplify interfacing to D/A
converters. Spurious frequency components in the output
sinusoid are less than -69dBc.
The NCO12 has applications as a Direct Digital Synthesizer
and modulator in low cost digital radios, satellite terminals,
and function generators.