SN74HC139N datasheet by Texas Instruments

SN74HC139N Frequently Asked Questions (FAQs)

• What is the maximum frequency of operation for the SN74HC139N?
  The maximum frequency of operation for the SN74HC139N is typically 25 MHz, but it can vary depending on the specific application and operating conditions.
• How do I ensure that the SN74HC139N is properly powered?
  To ensure proper power supply, connect VCC to a stable 5V power source, and GND to a reliable ground connection. Also, ensure that the power supply noise is minimized and decoupling capacitors are used to filter out high-frequency noise.
• What is the maximum current that the SN74HC139N can sink or source?
  The SN74HC139N can sink or source up to 25 mA of current per output pin, but it's recommended to limit the current to 10 mA or less to ensure reliable operation.
• How do I handle the enable inputs (E1 and E2) for proper operation?
  The enable inputs (E1 and E2) are active-low, meaning they must be pulled low to enable the decoder. Connect them to a logic low (GND) to enable the decoder, or to a logic high (VCC) to disable it.
• What is the propagation delay of the SN74HC139N?
  The propagation delay of the SN74HC139N is typically around 10-15 ns, but it can vary depending on the specific application and operating conditions.