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
Base station, relay station, and bandwidth allocation method
Using sets of OTDR receive fibers with different lengths of marker events to verify optical fiber connectivity
Vibration disturbance estimation and control
Pharmaceutical treatment process using chitosan or derivative thereof
Performance apparatus, a method of controlling the performance apparatus and a program recording medium
Human activity monitoring device
  Randomly Featured Patents
Modular step ramp
Fastening member for vertical board siding, method of fastening lower end of siding board using the fastening member, and structure fastened using the fastening member
High-tension high-compression foundation for tower structures
Timer state control optimized for frequent cancel and reset operations
Plate fin coil assembly
Modular system for obtaining equipped walls and workbenches, in particular for use in laboratories
Burst mode digital data amplifier circuit unit and amplifier circuit
Process for preparing aromatic amines in a fluidized-bed reactor
Corrosion inhibition with CU-BTA
Erasing head