SCLS263R December 1995 – October 2023 SN54AHCT74 , SN74AHCT74
PRODMIX
Refer to the PDF data sheet for device specific package drawings
Input signals must cross to be considered a logic LOW, and to be considered a logic HIGH. Do not exceed the maximum input voltage range found in the Absolute Maximum Ratings.
Unused inputs must be terminated to either VCC or ground. The unused inputs can be directly terminated if the input is completely unused, or they can be connected with a pull-up or pull-down resistor if the input will be used sometimes, but not always. A pull-up resistor is used for a default state of HIGH, and a pull-down resistor is used for a default state of LOW. The drive current of the controller, leakage current into the SNx4AHCT74 (as specified in the Electrical Characteristics), and the desired input transition rate limits the resistor size. A 10-kΩ resistor value is often used due to these factors.
Refer to the Feature Description section for additional information regarding the inputs for this device.