The linear to logarithmic converter (Q1701 and Q1711) at the input of the logarithmic to linear converter (Q1704 and Q1710) provides a means for generating a differential output current (that is) proportional to the phase offset control signal, i.e. maps the input current to the output, when enabled by the phase offset enable signal 137 (the transistor Q1705 is ???ON??? and the transistor Q1708 is