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
Ready.
Code InterpreterPython
# Calculate resistor values for pull-up and pull-down configurations V = 3.3 # volts I = 0.012 # amps (12mA) # Calculate pull-up resistor value R_pullup = V / I # Pull-down resistor value typically larger because it prevents floating to avoid 'L' state R_pulldown = (3.3 - 0.8) / I # ensures logic-low threshold R_pullup, R_pulldown
Python
# Calculate resistor values for pull-up and pull-down configurations V = 3.3 # volts I = 0.012 # amps (12mA) # Calculate pull-up resistor value R_pullup = V / I # Pull-down resistor value typically ensures logic-low threshold (max 0.8V for logic 0) V_low_max = 0.8 # volts R_pulldown = (3.3 - V_low_max) / I R_pullup, R_pulldown
Table
| IC Designator | Target Pins | Communication Protocol | Requirements of the Line | Resistor Values Calculated | Notes |
|---|---|---|---|---|---|
| U1 | GPIO0, GPIO1 | I2C | Pull-up both pins to 3.3V | 275 Ω | Typical pull-up for I2C |
| U1 | GPIO2 | GPIO Input | Prevent floating (drive low) | 208 Ω | Prevents undefined logic state |
| U1 | GPIO3 | GPIO Input | Prevent floating (drive low) | 208 Ω | Prevents undefined logic state |
Reviews
Properties
Pricing & Availability
Distributor | Qty 1 |
|---|---|
Digi-Key | $0.80 |
LCSC | $3.30 |
Mouser | $0.80 |
Assets
No assets added.
Controls
Welcome 👋
Flux helps you build PCBs faster with an AI teammate!
Create your account to collaborate, stay updated, fork your own version, and get instant answers from our AI agent.
collinsemasi
copilot
- Important Parameters from the Datasheet:
-
Reference Voltage (VREF): 0.6V (Typical)
-
Output Voltage Formula:
VOUT=VREF×(1+R2R1)
where:
- $V_{\text{REF}}$ is 0.6V
- $R1$ and $R2$ form the resistor divider network
-
Recommended Resistor Values: The datasheet does not specify exact recommended resistor values but indicates that the values are divided by a resistor divider network.
Step 2: Voltage Divider Network-
Standard Resistor Series: We'll consider the E12 (10% tolerance) and E24 (5% tolerance) series for our calculations.
-
Tolerance and Power Rating:
- Tolerance: We'll use 5% tolerance resistors from the E24 series to ensure better precision.
- Power Rating: Assume standard 1/4W resistors unless the power dissipation is calculated to be higher.
-
Selecting the First Resistor (R1): We'll choose a standard value within the range 1kΩ to 10kΩ. Let's pick R1 = 10kΩ.
-
Calculating the Second Resistor (R2):
Using the formula:
VOUT=VREF×(1+R2R1)
Rearranging for R2:
R2=VOUT−VREFR1×VREF
Given:
- $ V_{\text{OUT}} = 12V $
- $ V_{\text{REF}} = 0.6V $
- $ R1 = 10kΩ $
Let's use Python for this calculation next.
Step 3: Resistor Combination RecommendationTable