Resources Contact Us Home
Microcontroller chip with integrated LCD control module and switched capacitor driver circuit

Image Number 3 for United States Patent #5861861.

Apparatus for providing multiple of discrete voltage levels to drive a liquid crystal display (LCD) from an LCD module on board a microcontroller chip includes a charge pump with a switched-capacitor that develops the discrete voltages as multiples of the value of a base voltage that remains substantially without change irrespective of change in the supply voltage. A switched-capacitor charging circuit selectively charges a capacitor to produce successive additive charges individually retrievable from the capacitor. An LCD drive selectively transmits the discrete voltage levels to activate the LCD according to status of an external system under the control of the microcontroller. Voltage losses that may occur during the switched-capacitor charging are compensated to maintain the levels of the discrete voltages free of decay. Compensation is achieved by overcharging the capacitor by an amount substantially equivalent to the amount of voltage loss on the capacitor, using active feedback obtained from monitoring the charge on the capacitor.

  Recently Added Patents
Traffic flow analysis mitigation using a cover signal
Selected alert delivery in a distributed processing system
Wristband with detachable labels
Method for forming ventilation holes in an electrode plate
Aromatic amine derivative, organic electroluminescent element employing the same, and process for producing aromatic amine derivative
Vehicle driving assistance apparatus
Cartridge for conducting a chemical reaction
  Randomly Featured Patents
Electric feeding method and apparatus for a continuous plating apparatus
Apparatus and method for transmitting and receiving a signal in a communication system
Insulated gate static induction type thyristor
Food and beverage container nesting device
Self cleaning valve assembly
Method and apparatus for positioning a suture anchor
Docking connector
Watch bracelet
Polishing apparatus for end faces of optical fibers
Electric lamp with insulating base