Output driver for reducing transient noise in integrated circuits

An integrated circuit comprising:

• a plurality of parallel channels of digital circuitry;
• a plurality of connections including a first power supply pin, a second power supply pin, and a plurality of output terminals equal in number to the channels;
• a plurality of output driver circuits equal in number to the channels, each output driver having:
• a binary data input terminal;
• a plurality of first switches connected between the first power supply pin and the corresponding output terminal;
• first means as a binary signal at the input terminal changes from a first level to a second level for sequentially closing the individual first switches responsive to different voltage levels at the corresponding output terminal to increase the charging or discharging current in stepwise fashion as the corresponding output terminal is switched to the first power supply pin;
• switching means connected between the second power supply pin and the corresponding output terminal;
• and
• second means as a binary signal at the input terminal changes from the second level to the first level for closing the switching means to switch the corresponding output terminal to the second power supply pin.