Design of a High Precision and High stability Oscillator with External Synchronization

In this paper, a well designed bias block provides a supply-insensitive and temperature-insensitive current to bias the oscillator so that a supply-insensitive, temperature-insensitive and process-insensitive output frequency is acquired. The oscillator designed could be synchronized with external frequency in the range of 750 kHz-1.2 MHz compared with a 1 MHz intrinsic frequency. The duty cycle of output frequency is set by the internal circuit to be kept in the range of 76%-86%. Simulation results with HSPICE based on the 0.6 mum BiCMOS process show that the oscillator frequency error is less than 2.0% over a large range of temperature in all process corners. The oscillator can be widely used in many kinds of electronic circuits, especially in DC-DC converters.