It is shown that a digital phase locked loop can be designed tonperform the functions of capturing fundamental of an input referencenwave, and producing sine and cosine values of the phase angle to a 16nbit accuracy. Digital differential analyzers are used for continuousncalculation of the sine and cosine, since the simplicity of the hardwarenrequired reduces the number of cells needed for implementation in a gatenarray ASIC. In the implementation the variable frequency oscillatornoccupies 2586 cells the phase comparator 2711 cells, PI control 1196ncells, and compensating filters in the loop a total of 3018 cells.nAlternative methods would have required a significantly greater area, ornplaced an additional software burden on an existing processor. While thendevice is currently being incorporated into a power converter chip aimednat center frequencies of 40-60 Hz, with a lock band of ±8 Hz anwider frequency range is possible with a sacrifice of some accuracy innthe output values. A version for motor current control over a frequencynrange from 0-2000 Hz is being developed
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