The maximum frequency of operation for the SN74ALS09D is typically around 100 MHz, but this can vary depending on the specific application, supply voltage, and output load.
To ensure proper operation, the SN74ALS09D should be powered from a stable, low-noise power supply with a decoupling capacitor (e.g., 0.1 μF) placed close to the device. Additionally, the power supply voltage should be within the recommended range of 4.5 V to 5.5 V.
The input voltage threshold for the SN74ALS09D is typically around 1.5 V to 2.5 V, depending on the supply voltage. This means that an input voltage above 1.5 V to 2.5 V will be considered a logic high, and an input voltage below 1.5 V to 2.5 V will be considered a logic low.
While the SN74ALS09D is typically specified for 5 V operation, it can be used with a 3.3 V power supply, but the output voltage levels and noise margins may be reduced. Additionally, the device may not meet all of the specified timing and electrical characteristics at 3.3 V.
Unused inputs on the SN74ALS09D should be tied to a valid logic level (either VCC or GND) to prevent floating inputs and ensure proper device operation.
SN74ALS09D datasheet
by Texas Instruments
