Drive circuit for a display
AssigneeRockwell International Corporation
InventorJohn R. Spence
Life of this patent
Estimating the term…
Abstract
A compact circuit for selectively controlling the operation of a plurality of metal oxide semiconductor field effect transistors (MOSFETs) which drive a readout display, such as that found in a hand-held calculator, or the like. The circuit includes an internal power supply to develop a driving voltage (V.sub.gg), the magnitude of which is substantially boosted with respect to that of the calculator operating voltage (V.sub.DD). The circuit also includes an improved strobe driver connected between the display and the power supply to selectively apply the boosted driving voltage to a control electrode of any one of the plurality of MOSFETs.
Claims14
In combination:
- at least one first multi-terminal semiconductor device,
- source means to supply a reference potential signal,
- power supply means connected to said source for boosting said reference potential signal, and
- driver means connected between said power supply means and said at least one semiconductor device and adapted to selectively apply said boosted signal to a control electrode of said first semiconductor device to thereby drive said device,
- said driver means including second and third multiterminal semiconductor devices,
- the conduction path of said second semiconductor device selectively connected between said power supply means and the control electrode of said at least one first semiconductor device,
- the conduction path of said third semiconductor device connected between one conduction path electrode and the control electrode of said second semiconductor device so as to form a feedback path therebetween, and
- the control electrode of said third device connected to the one conduction path electrode of said second device.
In combination:
- at least one first multi-terminal semiconductor device,
- source means to provide a first reference potential signal,
- power supply means connected to said source means for boosting said first reference potential signal, and
- driver means connected between said power supply means and said at least one first semiconductor device to selectively apply said boosted signal to said first semiconductor device and thereby drive said device,
- said power supply means including second and third multi-terminal semiconductor devices,
- the respective conduction paths of each of said second and third semiconductor devices connected in electrical parallel with respect to one another between said source means and said driver means, the control electrode of said second device connected to one conduction path electrode thereof, and
- means to apply said boosted signal to the control electode of each of said second and third devices.
A circuit for driving a semiconductor device and comprising:
- reference potential source means,
- first and second inverter means,
- each of said inverter means having clock terminals to receive respective multi-phase clock signals,
- charge storage capacitor means, said charge storage capacitor means including first and second capacitors,
- transmission gate means having conduction path terminals selectively connected between one plate of said first capacitor and a control electrode of said semiconductor device to be driven, said transmission gate means having a control terminal connected to a first plate of said second capacitor,
- said first inverter means connecting the first plate of each of said first and second capacitors to said source means during a first of said multi-phase clock signals for charging said first and second capacitors and said transmission gate means control terminal, and
- said second inverter means connecting second plates of each of said first and second capacitors to said source means during a second of said multi-phase clock signals for boosting the charge of said first and second capacitors and said transmission gate means control terminal for driving said transmission gate means.
Dependencies are inferred from the claim text.