Relay Shield 2.1 VCC power capability
Account cancelled 2020-04-16 11:24:20 1771 Views1 Replies I don't see this on the wiki, but the row of pins marked D/VCC/GND (Digital IO on the wiki) which allow for 3 pin plug in connections to GPIO with easy power and ground. Again, on the wiki, these are marked Digital IO in the pinout section. I measure VCC at 5.4 V on my scope which I find kind of weird. The schematic shows VIN going to the 7805, which outputs 5V and then 5V goes through a diode to VCC. But that means I should be getting a lot closer to 5V, probably less than 5V from the diode, than 5.4. It definitely should not be MORE than the 5V labeled pins (which are 5.14 V on my scope).
That said, I can handle the voltage, but, how many milliamps can each Digital IO VCC pin source (not the GPIO itself)? How can VCC be measured at 5.4 volts if 5V is 5.14V? I'd like to know if I can source enough current to drive a combination of 14 Neopixels safely from one of the pins? That's about 840 ma full on, but I'll never have all of them on full. I expect at any give time to be using 4-6 leds at about 30 ma per led (Neopixels are 60 ma when RGB are all on full). I expect to never need to pull more than about 200 ma total give or take. This is for lighting a scene for a christmas setup, so I would do things like color lights, but dim, and then they are RGBW, so I can do white via the 20ma white LED instead of 3 at 60ma.
Note, I'm not talking about the relays. I'm using those for switching some other AC peripherals on and off. This is strictly the VCC labeled RED strip labeled Digital IO and numbered 13 through 0.
How much energy can those pins handle?
Thank you.
That said, I can handle the voltage, but, how many milliamps can each Digital IO VCC pin source (not the GPIO itself)? How can VCC be measured at 5.4 volts if 5V is 5.14V? I'd like to know if I can source enough current to drive a combination of 14 Neopixels safely from one of the pins? That's about 840 ma full on, but I'll never have all of them on full. I expect at any give time to be using 4-6 leds at about 30 ma per led (Neopixels are 60 ma when RGB are all on full). I expect to never need to pull more than about 200 ma total give or take. This is for lighting a scene for a christmas setup, so I would do things like color lights, but dim, and then they are RGBW, so I can do white via the 20ma white LED instead of 3 at 60ma.
Note, I'm not talking about the relays. I'm using those for switching some other AC peripherals on and off. This is strictly the VCC labeled RED strip labeled Digital IO and numbered 13 through 0.
How much energy can those pins handle?
Thank you.
