James J McDonald, Ii

Title: Innovations of James J McDonald, II

Introduction

James J McDonald, II is a notable inventor based in Gorham, ME (US). He has made significant contributions to the field of electronics, particularly in the design of circuits for voltage controlled oscillators and phase locked loops. With a total of 5 patents to his name, McDonald has demonstrated a commitment to advancing technology through innovative solutions.

Latest Patents

One of McDonald's latest patents is a circuit designed to linearize the gain of a voltage controlled oscillator over a wide frequency range. This circuit utilizes multiple delay stages, with the last stage looped back out of phase to the first stage. Each stage delay is formed by charging one or more capacitors, and the active components exhibit a square law relationship between the control voltage and the resulting current. This innovation allows for a linear relationship between the VCO frequency and the input control voltage, extending the linear range through the use of square law current sources.

Another significant patent involves circuitry to reduce the lock acquisition time in phase locked loops (PLLs). This design features multiple parallel charge pumps that are selectively disabled as the phase lock is approached. A lock detection circuit enables reference currents to be fed to the charge pumps, optimizing the error signal from a phase detector. This approach enhances the loop gain initially to reduce lock time and then smoothly transitions to a lower gain as the lock is achieved, minimizing switching noise through the operation of a low pass filter.

Career Highlights

James J McDonald, II is currently employed at Fairchild Semiconductor Corporation, where he continues to innovate in the field of electronics. His work has had a lasting impact on the development of efficient and reliable electronic circuits.

Collaborations

Throughout his career, McDonald has collaborated with notable colleagues such as Ronald B Hulfachor and Christian Klein. These partnerships have contributed to the advancement of his projects and the successful implementation of his inventions.

Conclusion

James J McDonald, II is a distinguished inventor whose work in circuit design has led to significant advancements in electronics. His innovative patents reflect his expertise and dedication to improving technology.