SN74HC138DR datasheet by Texas Instruments

SN74HC138DR Frequently Asked Questions (FAQs)

• What is the maximum frequency of operation for the SN74HC138DR?
  The maximum frequency of operation for the SN74HC138DR is 25 MHz.
• How do I ensure that the SN74HC138DR is properly powered?
  Ensure that the SN74HC138DR is powered with a stable 5V supply, and that the power supply noise is minimized. Also, ensure that the decoupling capacitors are placed close to the device.
• What is the maximum current that the SN74HC138DR can sink or source?
  The SN74HC138DR can sink or source up to 25 mA of current per output pin.
• How do I handle the enable inputs (E1, E2, and E3) of the SN74HC138DR?
  The enable inputs (E1, E2, and E3) are active-low inputs. To enable the device, all three enable inputs must be low. To disable the device, at least one of the enable inputs must be high.
• What is the propagation delay of the SN74HC138DR?
  The propagation delay of the SN74HC138DR is typically around 10-15 ns.