Hello, I'm just looking for some guidance on a project I'm working on. I have a R503 fingerprint reader and 0.96" OLED display that are powered by a D1 mini which is encased within a 3D printed enclosure. That circuit has been running happily 24/7 for months without issue.
I'm looking to add an active buzzer to this project and have got the buzzer running on a secondary test D1 mini but just want to check my wiring plans attached (sorry if they're a bit of a mess, not used any online diagram tools before) are correct before soldering up to the existing circuit. Only the active buzzer is changing here. I'm not too familiar with the hardware side of things so not sure if I've got the resistor/power stuff right.
There are loads of different examples online of wiring up an active buzzer.... some just directly wire up the pins to GND and D5, some use resistors in between and some also add capacitors. For my quick test I just used a 330Ω resistor I had. I've not really gone into resistors/capacitors before so I'm not sure if that's needed or not but looking for a reliable and safe circuit with everything else that is currently attached.
Thanks for any help, I know this will be an easy question to most here!
Some power usage if it helps:
- 5V Active buzzer - 3.5 - 5.5V. <25mA
- OLED 50% lit - 11.0mA
- R503 Typical touch standby voltage: 3.3V, Average current: 2uA. Working current: 20mA