An electronic timekeeping device includes bipolar integrated circuit implemented logic in combination with a liquid crystal display. The bipolar circuitry is configured to effectively implement logic functions with a supply voltage of 1 volt. Drive circuitry is coupled to the liquid crystal display to effectively impress an a.c. voltage across the liquid crystal cell. Logic of the drive circuitry is effective to provide out of phase voltages across the liquid crystal cell when display is required. When display is not required the voltages across the liquid crystal display cell are in phase such that effectively no potential difference is generated across the liquid crystal material.
An electronic device, having a liquid crystal display cell, includes a driving circuit for changing the state of the liquid crystal cell in accordance with the energized state of the cell thereby preventing the cell from deteriorating due to the energization by a direct current.
An electronic timekeeping system is implemented in bipolar integrated circuit technology for displaying time by way of a digital display. The bipolar circuitry is implemented utilizing integrated injection logic and has a stacked oscillator/regulator combination which provides a highly regulated timekeeping signal source. The regulator consumes a first amount of current in providing the regulated output, and the first amount of current is reconsumed by the series connected oscillator, thereby conserving system power.
A timing circuit in a digital watch with a two digit display. When the circuit is activated by a push button, the two display elements first display the hours information, for as long as the push button is depressed, and after release of the push button, the display elements show minutes for about one-half second before turning off.
A digital timing circuit in a digital watch with a two digit display. When said circuit is activated by a push button, the two display elements first display the hours information, next are blank for a short duration, then display the minutes information, then go blank until the button is pushed again.
First and second color liquid crystal display elements of the negative guest-host type are disposed in adjacent and opposing relation to each other and the color liquid crystal display elements provide display in different colors, at least one of electrodes of each color liquid crystal display element having formed therein a display pattern. By the control of a changeover switch, an alternating drive voltage is applied from a drive circuit to one of the first and second color liquid crystal display elements to change the color of a background of the display in accordance with the control of the changeover switch.
