SCLS997 March 2024 SN74LVC7002A-Q1
PRODUCTION DATA
Input signals must cross Vt-(min) to be considered a logic LOW, and Vt+(max) 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. These 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 is to 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 resistor size is limited by drive current of the controller, leakage current into the SN74LVC7002A-Q1, as specified in the Electrical Characteristics , and the desired input transition rate. A 10-kΩ resistor value is often used due to these factors.
The SN74LVC7002A-Q1 has no input signal transition rate requirements because it has Schmitt-trigger inputs.
Another benefit to having Schmitt-trigger inputs is the ability to reject noise. Noise with a large enough amplitude can still cause issues. To know how much noise is too much, please refer to the ΔVT(min) in the Electrical Characteristics . This hysteresis value will provide the peak-to-peak limit.
Unlike what happens with standard CMOS inputs, Schmitt-trigger inputs can be held at any valid value without causing huge increases in power consumption. The typical additional current caused by holding an input at a value other than VCC or ground is plotted in the Typical Characteristics.
Refer to Section 7.3 for additional information regarding the inputs for this device.