i want to make expansion PCB for ESP8266 and i'have read many discussion for Arduino BJT connection, but still need to ensure is it working with esp8266 to switch on 20mA 24DC buzzer.

and also what is suitable value for those component ?

Below is the Schematic :

enter image description here

  • \$\begingroup\$ 24 V is a fairly substantial voltage. The BJT may be fine for it, especially if there is enough base current (and we can't tell how much is needed because we don't know what the buzzer needs.) But there is always a risk with the I/O pin, especially if there is an accidental short. You'll have to write more about how much you value your ESP8266 (do you care a lot if it is damaged and are you willing to go to long lengths to protect it), and about the buzzer current requirements. If I had to guess, I'd say you can at least try this circuit without the IO pin. Just tie 3.3 V to R1 and see. \$\endgroup\$
    – jonk
    Commented Aug 13, 2021 at 1:02
  • \$\begingroup\$ @jonk the buzzer need at least 20mA, okey, i will follow your instruction, for the Diode do you have any suggestion suitable part number for this ? \$\endgroup\$ Commented Aug 13, 2021 at 1:50
  • \$\begingroup\$ No. Most anything is okay. You probably can get away without one. But if you have a diode you can just use it. \$\endgroup\$
    – jonk
    Commented Aug 13, 2021 at 1:56
  • \$\begingroup\$ okay i will follow as your suggestion 👍 \$\endgroup\$ Commented Aug 13, 2021 at 3:38


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.