Phase-Locked-Loop Control Of A Tuning Fork Oscillator
Original Publication Date: 1979-Aug-01
Included in the Prior Art Database: 2005-Feb-20
The disclosed circuit controls the mechanical multiplexing of a row of light-emitting diodes (LEDs) to produce a multiple-character alphanumeric display for use on a computer terminal or text-processing typewriter. The circuit sustains oscillation of a tuning fork mechanical resonator, regulates the amplitude of its oscillation, derives synchronizing pulses from signals generated by the tuning fork, and produces a burst of LED firing pulses. All of these features are made possible through the use of a phase-locked loop (PLL).