摘要:
The multiplex circuit inludes a cascade connection of flip-flop elements (118,120,122) for producing a high data-rate multiplexsignal. In order to avoid disturbances caused by parallel loading the flip-flop circuits, the slave-section (130) of the flip-flop generating the multiplexsignal is not parallel loaded, which results in a continuous outputsignal. This way of loading requires a specific flip-flop circuit as shown in the description.
摘要:
In integrated circuits the delay of the signal transitions has to lie within specified limits. This delay is partly determined by variations in the manufacturing process (process scatter). To compensate for the effect of this scatter a load capacitance 28 (figure 1) is connected via a switching element (26) to a node which is to be influenced in the integrated circuit. The switching element 26 receives a reference voltage VR1 which is dependent on the manufacturing process and is generated by reference source 2 , so that the node capacitance 26 is connected to the said node for a longer or shorter time, depending on the process scatter.
摘要:
In relatively large systems of (integrated) circuits data signals can experience a delay which is in the order of magnitude of a clock-pulse period. The receiving circuit (i.e. receiving the data signal) then receives the data signal too late (the clock pulse has ceased) and can at that moment no longer take over the data signal for further processing or transport. In the system according to the invention the clock pulses (CLK) are led via a delaying element (for example, the inverting circuits in series) (35) to the receiving circuit (slave of the master/slave flip-flop) (22). The data output of the receiving circuit is connected to a data input of another circuit (master of another master/slave flip-flop) (23), which receives the undelayed clock pulses (CLK), the data delay between the receiving circuit and the other circuit being negligible. The data delay is thus in fact distributed over two clock pulses.
摘要:
The invention relates to a memory device of the charge-coupled shift register type which is subdivided into four sections each of which has a storage capacity of, for example 208,800 bits and which can operate in different modes: parallel-in/parallel-out (as background video memory); 2x2 parallel-in, demultiplex/multiplex mode, for example for 100 Hz TV; scan mode; parallel-in-recirculation mode; "shortened" memory, for example for 525-line system, etcetera. Control is realized via a decoding and timing block in which a multi-bit control word is serially input and decoded. In a scan mode (for example, as a teletext memory), the memory sections are scanned one-by-one under the control of a separate scan register in which a scan bit (logic 1) is step-wise shifted until all sections have been read. Via a data output, the scan bit is transferred, for example to the scan register of a further memory device (via its serial data input) which is connected in series with the former memory device.