A system and method of generating an output signal of very precise frequency without the use of a crystal oscillator. An input signal is generated using any convenient such as an RC oscillator. A circuit for producing a frequency-controlled output signal comprises a phase lock loop having a VCO and a down counter. The down counter reduces the frequency of a VCO clock signal in accordance with a down count value. The down count value is loaded in a register and stored in non-volatile memory. The down count value is set during a calibration operation using a precision external clock signal. In this way, a clock signal with a highly precise frequency is generated without using a crystal oscillator.