I have a project that requires use of the Arduino Nano or any other microcontroller that gets the job done. It needs to be able to run a 3x10 LED array circuit or circular LED circuit. A RTC module, SD Card module, LCD screen, and a ultrasonic sensor. Is this possible to run on one Nano or anything else? I haven't tried much, I made a schematic that connects everything, but it definitely isn't right.

 

hi tyc,
Welcome to AAC.
Please check the orientation of your LED arrays.
E

 

Hi tyc,
There is no rectification of the AC input?
Also no capacitor filtering.
No DC fusing
No note of the transformer rating.

E

 

T1 primary is short-circuited by the two Gnd connections.
No decent current control for the LEDs.

 

LEDs backwards.
Q1 will not turn on well. You will drop about 1V across the transistor. Do you want that fixed?
Why different resistors for the LEDs.
What type of LEDs.
What supply voltage (5V)??

 

ya I am trying to fix that. Also didn't mean for different LED resistors, they should all be 47 ohms, not 1k. LEDs are 505nm (green blue). Supply voltage is 5V yes

 

You can put low voltage LEDs together, two in series. (1.5V+1.5V=3V) You must leave some voltage across the resistor. Maybe 1V or more. Most white LEDs need 3V. Each color is different.

Q4 cannot turn on well. You will drop 0.8 to 1V. The part may get hot. The Base voltage will be below +5V and the Emitter will be 0.65 below that.
Q3 is turned on well. (watch out for the inversion of the signal)

 

I use I2C for the displays...

That just uses A4 (SDA) and A5 (SCL), and it allows multiple I2C devices to share those 2 pins. There are a number of I2C port expanders that you could use to drive the LEDs too, or have you looked at the addressable LEDs like the WS2812B?

They just use 1 pin.

But you may run out of memory so a Raspberry Pi Pico could be a better choice as the controller.