The maximum frequency of operation for the M74HC138M1R is 25 MHz.
Ensure that the VCC pin is connected to a stable 5V power supply, and the GND pin is connected to a reliable ground. Also, decouple the power supply with a 0.1uF capacitor to reduce noise.
The M74HC138M1R can sink or source up to 20mA of current per output pin.
Connect the A0, A1, and A2 input pins to the 3-bit binary input, and the Y0-Y7 output pins will be asserted based on the input code. Use the E1 and E2 enable inputs to enable or disable the decoder.
The propagation delay of the M74HC138M1R is typically around 10ns, but can vary depending on the operating conditions and load capacitance.