I²C Bus Capacitance
Sum device input capacitance and wiring capacitance to estimate total I²C bus capacitance. Use datasheet values and include all connected devices; whether the result meets a limit depends on the I²C mode.
Description
Sum device input capacitance and wiring capacitance to estimate total I²C bus capacitance. Use datasheet values and include all connected devices; whether the result meets a limit depends on the I²C mode.
I²C Bus Capacitance: Sum device input capacitance and wiring capacitance to estimate total I²C bus capacitance. Use datasheet values and include all connected devices; whether the result meets a limit depends on the I²C mode.
When to use I²C Bus Capacitance
Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.
- Total device capacitance (pF)
- Required number input.
- Wiring capacitance (pF)
- Required number input.
How I²C Bus Capacitance works
Sum device input capacitance and wiring capacitance to estimate total I²C bus capacitance. Use datasheet values and include all connected devices; whether the result meets a limit depends on the I²C mode. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.1
- Total Capacitance pF
- The resulting total capacitance pf returned as a number.
Limitations and assumptions
- I²C pull-up and capacitance estimates depend on supply voltage, logic thresholds, sink-current limits, rise-time mode, trace and device capacitance, level shifters, topology, and bus speed. Confirm the complete bus against the applicable I²C timing specification and every device datasheet.
- Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.
Alternative or Complementary approaches
Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.
References
-
I2C — Wikipedia contributors
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