They used the PIC because the engineer that designed it didn’t have any gray hair. 😉 As you said overkill but they probably had one lab in school with a 555 and never saw it again. Years ago can’t tell you how many 555, 556(7), 741 I used …. All the work horses!
@@RobRoschewsk another big reason is reduced inventory. If they have one product that needs that part, the R&D teams will be encouraged to make as much use of it as possible.
BTW the company that supply the control board wanted over £270 for a replacement and wouldn't share the schematic to help either. I would estimate no more than £30 worth of components, including the PCB.
You could, but remember the output will be a fixed duration. If the length of the switch press is important to your project, then you can still use the 555 as de-bounce, but in a different manner. See my "Switch De Bounce Using a 555 Timer Chip" video (link below):- th-cam.com/video/mfoYkVQkLyc/w-d-xo.htmlsi=35hLxNfdUxvZ59md
Ahh... end of the video: "Just throw a PIC (or Arduino) at it!" Thank you for this anecdote. Designers of modern devices seem to have forgotten the KISS principle. Yes, PICs are so cheap these days that the incremental BOM cost vs. a 555 in a device that costs more than ~$40 is probably lost in the noise. But what about repairability? If the PIC gets fried for whatever reason, you can't replace it without access to the original firmware image! Lack of awareness/understanding of how to do simple things without a microcontroller in the loop is a pet peeve, TBH. Taken this even further to its illogical extreme, we have devices performing seemingly simple functions which can't operate without a WiFi connection to "The Cloud"...
So very true. It's so much more rewarding if you develop solutions without resorting to software. Microcontrollers are amazing developments and certainly have their place. I also feel that a lot of young enthusiasts start out in the world of low cost microcontrollers and begin learning electronics from there.
IIRC, there's another version of this circuit that resets regardless of whether the button is still pressed. Basically when you press the button, it creates a short pulse and the output resets regardless of whether rhe button is srill being held down. It's a really useful circuit for creating very short pulses faster than you can press an release a button. Unfortunately I cannot for the life of me remember how it's done. 🤨
You use an extra resistor, an extra capacitor and a diode, all connected to the trigger pin. The capacitor goes between the extra resistor/push button and the trigger pin. The diode is there to limit the overshoot voltage to the NE555. The capacitor means that the trigger input only ever sees a pulse, never a constant voltage.
They used the PIC because the engineer that designed it didn’t have any gray hair. 😉 As you said overkill but they probably had one lab in school with a 555 and never saw it again. Years ago can’t tell you how many 555, 556(7), 741 I used …. All the work horses!
😆
@@RobRoschewsk another big reason is reduced inventory. If they have one product that needs that part, the R&D teams will be encouraged to make as much use of it as possible.
BTW the company that supply the control board wanted over £270 for a replacement and wouldn't share the schematic to help either. I would estimate no more than £30 worth of components, including the PCB.
is this how you do a debouncer?
Exactly
You could, but remember the output will be a fixed duration. If the length of the switch press is important to your project, then you can still use the 555 as de-bounce, but in a different manner. See my "Switch De Bounce Using a 555 Timer Chip" video (link below):-
th-cam.com/video/mfoYkVQkLyc/w-d-xo.htmlsi=35hLxNfdUxvZ59md
What offset value has that Resistor network?
Not quite sure what you mean. Presume you mean the additional unwanted resistance of the PCB and connectors?
wow and pearl chicken or pearl hens is different than common chicken its new for me and i dont know where its come from sir
Ahh... end of the video: "Just throw a PIC (or Arduino) at it!"
Thank you for this anecdote.
Designers of modern devices seem to have forgotten the KISS principle. Yes, PICs are so cheap these days that the incremental BOM cost vs. a 555 in a device that costs more than ~$40 is probably lost in the noise. But what about repairability? If the PIC gets fried for whatever reason, you can't replace it without access to the original firmware image!
Lack of awareness/understanding of how to do simple things without a microcontroller in the loop is a pet peeve, TBH. Taken this even further to its illogical extreme, we have devices performing seemingly simple functions which can't operate without a WiFi connection to "The Cloud"...
So very true. It's so much more rewarding if you develop solutions without resorting to software.
Microcontrollers are amazing developments and certainly have their place. I also feel that a lot of young enthusiasts start out in the world of low cost microcontrollers and begin learning electronics from there.
IIRC, there's another version of this circuit that resets regardless of whether the button is still pressed. Basically when you press the button, it creates a short pulse and the output resets regardless of whether rhe button is srill being held down. It's a really useful circuit for creating very short pulses faster than you can press an release a button. Unfortunately I cannot for the life of me remember how it's done. 🤨
You use an extra resistor, an extra capacitor and a diode, all connected to the trigger pin. The capacitor goes between the extra resistor/push button and the trigger pin. The diode is there to limit the overshoot voltage to the NE555. The capacitor means that the trigger input only ever sees a pulse, never a constant voltage.
@Mark1024MAK thank you. I knew it wasn't an overly extravagant set-up