A novel design for deadzone-less fast charge pump with low harmonic content at the output

A novel design for a charge pump is presented. Unlike common charge pumps where the transistors are operating as switches, in this design transistors are kept in their saturation region at all times. This design has resulted in faster operation of the pump in addition to lower levels of output harmonic content. The actual strong point of this design is the smooth change of the output current. This may result in small spurious and phase noise levels if this charge pump is used in a PLL or frequency synthesizer. Comparison of simulation results for this circuit and those of a regular charge pump reveals the potential superiority or this design over traditional circuits.

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