Chat

Welcome to Flux

Treat Flux like your intern. Tell it what you'd like to build and it'll get to work. You can also ask it questions, brainstorm ideas, and teach it your preferences. Learn More

Explain project
Write a project description
Find schematic issues
Create a test plan
Simulate a circuit
Prepare for Manufacturing
Component Selection Workflow
New Subsystem Wizard
Write I2C initialization code
Generate firmware skeleton
I would like to connect about 10 LED to the circuit and control them individualy
perle

perle

@copilot I would like to connect about 10 LED to the circuit and control them individualy
2y

copilot

To individually control about 10 LEDs using the ATTINY412-SSF (U1) in your project, you'll need to use a technique to expand the number of GPIO pins, as the ATTINY412 has limited IOs. Two common approaches are using a shift register or an I²C GPIO expander. Given the components listed in your project, using an I²C expander seems more inline with your current design approach, considering you're already using I²C with U2 (VL53L0CXV0DH/1).
An I²C GPIO expander, like the MCP23017 from Microchip, offers 16 additional GPIO pins over the I²C bus, which would be more than sufficient for your 10 LEDs. Here's how you could integrate this into your project:
  1. Add an I²C GPIO Expander: Choose MCP23017 for expanding GPIOs via I²C.
  2. Connect the Expander to the ATTINY412:
    • Connect U1:PA2 (SDA) to MCP23017:SDA
    • Connect U1:PA1 (SCL) to MCP23017:SCL
    • Connect U1:VCC to MCP23017:VDD
    • Connect U1:GND to MCP23017:VSS
    This setup utilizes the existing I²C bus formed between U1 (ATTINY412) and U2 (VL53L0CXV0DH/1).
  3. Connect LEDs to GPIO Expander:
    • You'll connect the cathode (-) of each LED to a GPIO pin on the MCP23017.
    • The anode (+) of each LED should be connected to the positive voltage through an appropriate current-limiting resistor.
  4. Current-Limiting Resistors:
    • It's crucial to use current-limiting resistors for each LED to prevent them from drawing too much current.
    • Assuming each LED has a forward voltage ($V_F$) of about 2V and a desired forward current ($I_F$) of 20mA, and you're powering them from a 3V source, the resistor value ($R$) can be calculated using Ohm’s law: $R = \frac{V_{source} - V_F}{I_F}$.
    • In this case, $R = \frac{3V - 2V}{20mA} = 50\Omega$.
    Given these assumptions, here's how you'd connect one of the LEDs as an example:
    • Connect LED1 Anode to BATT1:(+) through a 50Ω resistor.
    • Connect LED1 Cathode to one of the GPIO pins on MCP23017.
Repeat the connection for each LED, ensuring each is connected to a unique GPIO pin on the MCP23017.
Programming the ATTINY412:
  • To control the LEDs, you'll program the ATTINY412 to send I²C commands to the MCP23017, setting its GPIO pins high or low to turn the LEDs on or off, respectively. This involves using an I²C library compatible with the ATTINY412 and writing the logic for LEDs' control.
Please Note: Adjust the resistor values based on the actual forward voltage and desired forward current of your LEDs. The calculation assumes typical values for common LEDs.
2y
Someone is typing...
4
U4
BATT1
SW1
U1
U2

No files yet

Documents

    Documents are markdown text files which describe project goals, capture details, or even simulation outputs.

    Assets

    Assets are files uploaded to this project which can be used in various ways.

    Precise Turquoise Matter Compiler thumbnail
    A ToF based pcb that controls some LEDs.

    Properties

    Properties describe core aspects of the project.

    Pricing & Availability

    Distributor

    Qty 1

    Digi-Key

    $7.52–$11.97

    LCSC

    $8.80

    Mouser

    $11.02

    Controls