TheCircuitDogOhm's Law Calculator
Use Ohm’s law to solve voltage, current, resistance or electrical power in an ideal resistive DC circuit.
Open calculator →Calculate · Diagnose · Design
Electronics engineering, explained with real numbers.
Practical circuit calculators, power-sequencing checklists and hardware troubleshooting guides. Built to make engineering concepts easier to understand—not to replace your datasheet.
Explore 15 free calculatorsTHE CIRCUIT DOG // TOOLKIT
> V = I × R> τ = R × C> PLDO ≈ (Vin−Vout) × I> f₀ = 1 / (2π√LC)All calculator logic runs locally in your browser.Featured calculators
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15 interactive calculators for power, analog, digital, and PCB work—no signup or backend.
Voltage Divider Calculator
Find the output of a two-resistor divider. Add an optional load resistance to estimate how the load pulls the output down.
Open calculator →LED Resistor Calculator
Size a series resistor for one or more LEDs in a string. The calculator estimates the resistor value and power dissipation.
Open calculator →RC Time Constant Calculator
Estimate first-order resistor-capacitor timing, including the 63.2% charge time and the approximate −3 dB low-pass corner.
Open calculator →Series and Parallel Resistor Calculator
Enter resistor values in ohms, separated by commas or spaces, and select a series or parallel connection.
Open calculator →Series and Parallel Capacitor Calculator
Enter capacitances in microfarads. This tool computes ideal series and parallel capacitance.
Open calculator →Hardware know-how
Bench-first engineering guides
Power Sequencing and PGOOD Logic
When one supply enables another through PGOOD, the important signals are the actual voltage waveforms—not the appearance of a status LED.
Read guide →Choosing Power-Good Pull-Ups
A pull-up resistor on a PGOOD output is not just a formality: it determines rise time and the current the driving transistor must sink.
Read guide →LDO and DC-DC Regulator Startup Troubleshooting
A regulator that occasionally needs a manual jump-start may be experiencing an enable threshold issue, input collapse, output overload, thermal shutdown or an unintended back-power path.
Read guide →