Integrated circuitry systems

A circuitry system comprising first and second IC chips, configured or configurable such that:

• the first IC chip has an output terminal connected to receive an output signal from an output-signal unit of the first IC chip, the output-signal unit being connected between high and low voltage-reference sources of the first IC chip, the high and low voltage-reference sources being connected to respective high and low voltage-reference terminals of the first IC chip;
• and
• the second IC chip has an input terminal connected in a potential-divider arrangement between high and low voltage-reference terminals of the second IC chip,
• wherein:
• the high and low voltage-reference terminals of the first IC chip are respectively connected to the high and low voltage-reference terminals of the second IC chip;
• and
• the output terminal of the first IC chip is connected to the input terminal of the second IC chip for transmission of the output signal from the first IC chip to the second IC chip,
• and wherein:
• the output-signal unit and potential-divider arrangement are configured or configurable such that the resistance they present between the high and low voltage-reference sources when the output signal has a logic low value and the resistance they present between the high and low voltage-reference sources when the output signal has a logic high value are substantially the same as one another;
• or
• the output-signal unit is configured to present a first on resistance between the high voltage-reference source and the output terminal when the output signal has the logic high value and to present a second on resistance between the low voltage-reference source and the output terminal when the output signal has the logic low value, and said first and second on resistances are substantially the same as one another;
• or
• the potential-divider arrangement is configured or configurable to present a first potential-divider resistance between the high voltage-reference source and the input terminal and to present a second potential-divider resistance between the low voltage-reference source and the input terminal, and said first and second potential-divider resistances are substantially the same as one another.

A circuitry system comprising first and second IC chips, configured or configurable such that:

• the first IC chip has an output terminal connected to receive an output signal from an output-signal unit of the first IC chip, the output-signal unit being connected between high and low voltage-reference sources of the first IC chip, the high and low voltage-reference sources being connected to respective high and low voltage-reference terminals of the first IC chip;
• and
• the second IC chip has an input terminal connected in a potential-divider arrangement between high and low voltage-reference terminals of the second IC chip,
• wherein:
• the high and low voltage-reference terminals of the first IC chip are respectively connected to the high and low voltage-reference terminals of the second IC chip;
• and
• the output terminal of the first IC chip is connected to the input terminal of the second IC chip for transmission of the output signal from the first IC chip to the second IC chip,
• and wherein:
• the circuitry system is configured or configurable such that the output terminal of the first IC chip is connected to the input terminal of the second IC chip via a transmission line connection;
• and
• the input impedance of the transmission line is equal to the on-resistances of the output-signal unit when the output signal has a logic low value and when the output signal has a logic high value, and/or the first and second potential-divider resistances each have a resistance twice the input impedance of the transmission line.