pcb

Calculates the current-limiting resistor for driving one or more LEDs in series from a DC supply. Computes the exact resistance from R = (Vsupply - n*Vf) / I, then selects the nearest E24 standard resistor value. Reports the actual current with the standard resistor, power dissipation, and voltage across the resistor. Supports series LED strings by specifying led_count. Validates that supply voltage exceeds total forward voltage. Chain from ohms_law for power budgeting or into trace_width for PCB layout.

post/api/led_resistor

Request

  • Base URL: https://calc.engineer
  • URL: https://calc.engineer/api/led_resistor
  • Auth: none declared

Request body

supply_voltage_vnumber required

Supply voltage in volts (V). Must be positive.

led_forward_vnumber

LED forward voltage in volts (V). Defaults to 2.0V (typical red LED).

led_current_manumber

Desired LED current in milliamps (mA). Defaults to 20mA.

led_countnumber

Number of LEDs in series. Defaults to 1.

Response

Computed result for led_resistor

toolstring required
versionstring required
computed_atstring date-time required

Changes

No recorded changes to this operation across all 1 revision of this API.