Power supply unit for data viewing devices

Details Power supply unit for data viewing devices Power supply unit for data viewing devices

1976-06-10

1978-03-14

Griffin, Robert L.

Facsimile and static presentation processing

Facsimile

Specific signal processing circuitry

358190, 358194, H04N 504, H04N 318, H04N 544

Patent

active

040794180

ABSTRACT:
The invention relates to a power supply unit for data viewing devices, which, from a main alternating voltage produces at least one d.c. voltage for the operation of the data viewing device, where the power supply unit is in the form of a switching power supply unit and contains an oscillator which produces signals which determine the switching frequency of the switching power supply unit and where the data viewing device contains a pulse generator which, in order to produce an image on a screen, produces timing pulses of a given repetition frequency and a given duration.
More particularly, the control stage for a switching power supply unit of a data viewing device having a display screen includes a free-running oscillator whose frequency is synchronized by timing pulses from a pulse generator. These pulses are of a predetermined repetition frequency and a given duration. The oscillator is preferably an astable multivibrator. The output signal of the oscillator is pulse modulated and fed to the base of a switching transistor in the power supply circuit. A separator stage such as an optical coupling element or transformer, is provided in the circuit between the pulse generator and the oscillator. The oscillator may contain an amplifier provided with a positive feedback and a negative feedback and which oscillator has its control input connected to the non-inverting input of the amplifier. The non-inverting input of the amplifier preferably includes a capacitor.

REFERENCES:
patent: 3432737 (1969-03-01), Hunter et al.
patent: 3818128 (1974-06-01), Chambers et al.
patent: 3869566 (1975-03-01), Smith
patent: 3989995 (1976-11-01), Peterson

Affiliated with

Also associated with

Rating

Power supply unit for data viewing devices does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Power supply unit for data viewing devices, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Power supply unit for data viewing devices will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2233493