Abstract: A compound type keyboard detector is disclosed. It comprises a time-sequencing generator, a keyboard scanner, a column input port and a row input port, a column lock and a row lock, a keyboard-synchronization detector, a keyboard detector and a keyboard decoder. With the unique design of the keyboard detector in conjunction with the various circuits that are associated therewith, a given number of pins can be used for a relatively greater number of input keys, or a smaller number of pins can be used for relatively complicated input keyw. This type of keyboard detector is good for small IC products, and can reduce the manufacturing cost thereof.

Abstract: An encoding control device includes a voltage provider providing different voltage levels at different instances, a data control device electrically connected to the voltage provider and outputting data respectively corresponding to the voltage levels, and an encoding device electrically connected to the data control device for encoding according to the data. The present encoding control device effectively reduces the pin number of an IC package.

Abstract: A digital phase-locked loop locks to the reference clock signal in the encoded input data stream and separates the reference clock signal from the actual data signal. The digital phase-locked loop includes a digital oscillator that generates a pulse train with a period continuously adjusted in accordance with time variations in the input data stream so as to maintain the regenerated data in proper phase relationship with the reference clock. The digital phase-locked loop also contains a predict phase generator that generates a predict phase with a fraction part in order to improve the precision of phase adjustment without increasing frequency of the system clock. The circuit also includes a digital low pass filter that generates a first order predict phase, of which the small transient phase variation in the reference clock is removed such that the frequency stability of the recovered reference clock is enhanced.

Abstract: A cost-effective and/or convenient digital plate being palpably controllable is provided. The digital plate includes an induction plate capable of inducing a change of a parameter when in contact with an object having a reactant property, a measurer for sensing the change, and a controller having an output for converting the change into a parametral information to be sent to the output.

Abstract: A digital-to-analog converter includes a generator responsive to a digital input signal, a set of switches each being directly connected to the generator, and a first and a second terminals connecting therebetween a resistor device having a plurality of nodes directly connected to the switches in order that a node voltage can be obtained between one of the nodes and one of the terminals to serve as an analog signal. Such converter has a low distortion/noise and can be used in a broad source voltage scope.

Abstract: An erasable and programmable seven segment display driver includes an oscillator, a signal source selector, a column address generator, a row address generator, a common signal driver, a segment signal driver, an EPROM array, and a seven segment display. A set of preset numerical data is stored in the EPROM memory array for display. The data stored in the memory is programmable and erasable, so numerical data can be reprogrammable in accordance with any desired display data. It is possible to lower the cost and enhance the usability and convenience of the display driver.