Patent ID: 7327179

Claim:
A pulse generator comprising: an oscillator; a selecting arrangement; a plurality of variable delay elements of the same type arranged as first and second groups, each delay element having a delay control input for controlling the delay (T D ) provided by the element, the selecting arrangement being arranged to select how many of the delay elements of the first group are connected in series to an output of the pulse generator, the delay elements of the second group being connected in series, the inputs of the first and second groups being connected to the output of the oscillator; a measuring circuit for repeatedly measuring the delay (IPD) provided by the second group; a reference pulse generator for generating a series of reference pulses (RP), each of which is of predetermined duration (IRD) equal to a predetermined fraction of the period of output pulses (IF clock) of the oscillator; and a control circuit whose output is connected to the delay control inputs of all of the delay elements and which is arranged to control the delay (T D ) provided by each element such that each measured delay (IPD) has a predetermined relationship with the predetermined duration (IRD).