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Calculadora de Ancho de Pista PCB por Corriente

POSThttps://rftools.io/api/py/v1/calculate

Slug trace-width-current. Calcula el ancho mínimo de pista PCB necesario para conducir una corriente dada según IPC-2221.

Entradas

Envíe cada una de estas en inputs, en las unidades indicadas. La mayoría son obligatorias: una llamada a la que le falte una se rechaza (400) y no cuesta nada; una de la que la calculadora puede prescindir toma el valor predeterminado indicado. Una entrada fuera de su rango se calcula igualmente y se marca en la procedencia.

Entradas de trace-width-current
Nombre	Unidad	Rango	Valor predeterminado	Descripción
currentnúmero	A	0.01 … 100	1	Corriente RMS a través de la traza
copperWeightnúmero	oz	0.5 … 4	1	Grosor del cobre (1 oz = 35 μm = 1,378 mil)
tempRisenúmero	°C	1 … 100	10	Incremento de temperatura permitido sobre la temperatura ambiente
traceLengthnúmero	mm	1 … 10000	100	Longitud de la traza (para resistencia/caída de tensión)
isExternalnúmero	ninguna	0 … 1	1	Las capas internas transportan menos corriente que las externas con el mismo ancho e incremento de temperaturaUno de: 1 Capa externa (exterior) · 0 Capa interna
traceWidthnúmero	mm	0.01 … 100	0.5	El ancho tal como se dibuja: la comprobación de la norma lo juzga, y la resistencia en CC, la caída de tensión y la potencia se calculan para él; los anchos mínimos no lo usan
boardThicknessnúmero	mm	0.2 … 6	1.6	El espesor de toda la placa. Solo lo usa el ancho para esta placa (modelo térmico de rftools); el modelo está validado de 1,4 a 3,2 mm
planeDistancenúmero	mm	0 … 6	0	El dieléctrico entre la traza y el plano de cobre continuo más cercano por debajo; 0 significa sin plano. Solo lo usa el ancho para esta placa
planeCopperWeightnúmero	oz	0.5 … 2	0.5	El peso del cobre de ese plano (35 µm por onza). Solo lo usa el ancho para esta placa, y solo cuando hay un plano
standardnúmero	ninguna	0 … 1	0	La gráfica con la que se comprueba la corriente: la curva externa o interna de IPC-2221A, o la gráfica conservadora de IPC-2152 para todo conductorUno de: 0 IPC-2221A Fig. 6-4 · 1 IPC-2152 Fig. 5-1

Salidas

Se devuelven en values, por nombre. Un valor ilimitado o no definido es null.

Salidas de trace-width-current
Campo	Unidad	Descripción
width2221mm	mm	Ancho mínimo (IPC-2221)
width2152mmprincipal	mm	Ancho mínimo (IPC-2152 Fig. 5-1)
resistance	Ω	Resistencia en CC (ancho dibujado)
voltageDrop	V	Caída de tensión (ancho dibujado)
powerDiss	W	Disipación de potencia (ancho dibujado)
inChartRange	ninguna	Dentro del rango de IPC-2152 Fig. 5-1
widthBoardMm	mm	Ancho mínimo (esta placa, modelo térmico)
inModelRange	ninguna	Dentro del rango del modelo térmico
limitCurrent	A	Límite de corriente
limitPercent	%	Porcentaje del límite
minTraceWidth	mm	Ancho conforme

Cómo llamarla

Calcular: una llamada, la solicitud y la respuesta completas, y sus errores.
Cálculo por lotes: esta calculadora con otras, o un barrido, en una sola solicitud.
Resolver para un valor objetivo: el valor de una entrada que lleva una salida a un objetivo.

curl -X POST https://rftools.io/api/py/v1/calculate \
  -H "X-API-Key: $RFTOOLS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "slug": "trace-width-current",
    "inputs": {
      "current": 1,
      "copperWeight": 1,
      "tempRise": 10,
      "traceLength": 100,
      "isExternal": 1,
      "traceWidth": 0.5,
      "boardThickness": 1.6,
      "planeDistance": 0,
      "planeCopperWeight": 0.5,
      "standard": 0
    }
  }'

import rftools

client = rftools.Client()  # reads RFTOOLS_API_KEY, or the key `rftools login` saved

result = client.calculate("trace-width-current", {
    "current": 1,
    "copperWeight": 1,
    "tempRise": 10,
    "traceLength": 100,
    "isExternal": 1,
    "traceWidth": 0.5,
    "boardThickness": 1.6,
    "planeDistance": 0,
    "planeCopperWeight": 0.5,
    "standard": 0,
})
print(result.values)
print(result.warnings, result.provenance.formula_ref)

const response = await fetch("https://rftools.io/api/py/v1/calculate", {
  method: "POST",
  headers: {
    "X-API-Key": process.env.RFTOOLS_API_KEY,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "slug": "trace-width-current",
    "inputs": {
      "current": 1,
      "copperWeight": 1,
      "tempRise": 10,
      "traceLength": 100,
      "isExternal": 1,
      "traceWidth": 0.5,
      "boardThickness": 1.6,
      "planeDistance": 0,
      "planeCopperWeight": 0.5,
      "standard": 0
    }
  }),
});
console.log(response.status, await response.json());

package main

import (
	"bytes"
	"fmt"
	"io"
	"net/http"
	"os"
)

func main() {
	body := []byte(`{
	  "slug": "trace-width-current",
	  "inputs": {
	    "current": 1,
	    "copperWeight": 1,
	    "tempRise": 10,
	    "traceLength": 100,
	    "isExternal": 1,
	    "traceWidth": 0.5,
	    "boardThickness": 1.6,
	    "planeDistance": 0,
	    "planeCopperWeight": 0.5,
	    "standard": 0
	  }
	}`)
	req, err := http.NewRequest("POST", "https://rftools.io/api/py/v1/calculate", bytes.NewReader(body))
	if err != nil {
		panic(err)
	}
	req.Header.Set("X-API-Key", os.Getenv("RFTOOLS_API_KEY"))
	req.Header.Set("Content-Type", "application/json")
	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()
	out, _ := io.ReadAll(res.Body)
	fmt.Println(res.Status, string(out))
}

application/json

{
  "slug": "trace-width-current",
  "values": {
    "width2221mm": 0.30038652083330486,
    "width2152mm": 0.7814374629086279,
    "resistance": 0.10433004926108375,
    "voltageDrop": 0.10433004926108375,
    "powerDiss": 0.10433004926108375,
    "limitCurrent": 1.4468880626650513,
    "limitPercent": 69.11384686926509,
    "minTraceWidth": 0.30038652083330486,
    "inChartRange": 1,
    "widthBoardMm": 0.3021150755977321,
    "inModelRange": 1
  },
  "warnings": [],
  "errors": [],
  "provenance": {
    "method": "calculator:trace-width-current",
    "version": "api@3f2c1a9b04de",
    "formulaRef": "IPC-2221A (May 2003) §6.2, Figure 6-4 (the chart of IPC-2221, February 1998), through its published fit; IPC-2152 (August 2009) §5, Figure 5-1; the board-specific width: rftools thermal model (board-specific), fitted to its own 2-D solver and checked against Brooks & Adam (2015), Jouppi (2010) and Olson (2010)",
    "assumptions": [
      {
        "code": "ipc-2221-fit",
        "text": "The IPC-2221 width is IPC-2221 Figure 6-4 through its published fit A = (I/(k·ΔT^0.44))^(1/0.725), with A in mil², k = 0.048 for an external layer (chart A) and 0.024 for an internal one (chart C). Chart A draws 10 to 100 °C and chart C 10 to 45 °C, both to 700 sq mil; the curves include IPC-2221’s 10 % derating, and its note 2 (a further 15 % for boards 0.8 mm or thinner or copper 108 µm or thicker) is not applied."
      },
      {
        "code": "ipc-2152-figure-5-1",
        "text": "The IPC-2152 width is read on IPC-2152 Figure 5-1, the chart IPC-2152 recommends for internal and external conductors in all environments, through the same fit with k = 0.024 on either layer. It is the conservative answer for a board about which nothing else is known: IPC-2152’s detailed method, which narrows the trace for the board’s thickness and a copper plane under it, is not applied."
      },
      {
        "code": "steady-state-dc",
        "text": "Steady DC (or RMS) current in a single trace: pulsed currents, skin effect and heating from neighbouring traces are not modelled."
      },
      {
        "code": "copper-weight",
        "text": "Copper is 35 µm (1.378 mil) thick per ounce, and the trace cross-section is a rectangle of that thickness."
      },
      {
        "code": "standards-check-chart",
        "text": "The standards check reads the drawn width on IPC-2221A Figure 6-4’s curve for the layer, or on IPC-2152’s conservative Figure 5-1, which is IPC-2221’s internal curve, for either layer. It applies neither the further 15 % derating Figure 6-4 suggests for boards 0.8 mm thick or less and copper 108 µm thick or more, nor IPC-2152’s detailed charts and modifiers."
      },
      {
        "code": "resistance-at-temperature",
        "text": "Resistance, voltage drop and power are for the drawn trace width, with ρ = 1/58 Ω·mm²/m (IEC 60028, 1.7241×10⁻⁸ Ω·m) at 20 °C and α = 0.00393 /°C, evaluated at a 25 °C ambient plus the allowed rise."
      },
      {
        "code": "thermal-model-own-method",
        "text": "The board-specific width is the rftools thermal model (board-specific): the site's own steady-state model of a long trace on an FR-4 board in still air, with an optional copper plane under it. It is not IPC-2152 and does not read IPC-2152's charts; it is a closed form fitted to a committed 2-D solver, which is checked against published results (Brooks & Adam 2015; Jouppi 2010; Olson 2010)."
      },
      {
        "code": "thermal-model-fr4",
        "text": "The laminate is FR-4, conducting 0.8 W/(m·K) in the plane of the board and 0.3 W/(m·K) through it (Graebner 1995; Azar & Graebner 1996). A laminate that conducts less runs hotter."
      },
      {
        "code": "thermal-model-still-air",
        "text": "The board is horizontal, in still air at sea level. Its faces lose heat by natural convection (the McAdams horizontal-plate correlations, over the 51.2 mm length of the IPC-TM-650 2.5.4.1A test board) and by radiation, with an emissivity of 0.9 for the laminate and 0.1 for the bare copper trace. Forced air, an enclosure and other orientations are not modelled."
      },
      {
        "code": "thermal-model-long-trace",
        "text": "The trace is long and alone. Heat drawn off through pads, vias and leads at its ends, and heat from neighbouring traces and components, are not modelled; a short trace with heat-sunk ends runs cooler."
      },
      {
        "code": "thermal-model-plane",
        "text": "An internal trace lies at the middle of the board's thickness. A plane is one solid copper layer under the trace, across a 76.2 mm (3 in) wide board, the stated distance of dielectric below the trace. A plane above the trace, a second plane, or a plane cut away under the trace is not modelled."
      },
      {
        "code": "thermal-model-margin",
        "text": "The board-specific width includes a 15 % margin for the model's measured disagreement with published data: it is the width at which the model's rise is the allowed rise divided by 1.15."
      },
      {
        "code": "thermal-model-heat",
        "text": "The model's Joule heat uses the copper resistivity of IPC-TM-650 2.5.4.1A, 10.827 Ω·cmil/ft at 25 °C for 1 oz and heavier copper and 11.529 Ω·cmil/ft for lighter, rising 0.393 % per °C. The resistance and power outputs keep 1/58 Ω·mm²/m."
      },
      {
        "code": "thermal-model-ambient",
        "text": "The board-specific width is computed at a 25 °C ambient, the temperature IPC-TM-650 2.5.4.1A tests at; the allowed rise is above that ambient."
      },
      {
        "code": "thermal-model-range",
        "text": "Outside the model's validated range (Width 0.25–5.1 mm (internal from 1.27 mm), copper ½–3 oz, board 1.4–3.2 mm, a plane from 0.1 mm under the trace to where it fits, plane copper ½–2 oz, rise 5–100 °C, ambient 0–85 °C) the board-specific width is still reported, flagged with a warning naming the bound. On boards thinner than 1.4 mm, IPC-2152's published thickness data show traces running hotter than the model predicts, so the IPC-2152 Figure 5-1 width is the one to use there."
      }
    ],
    "validRange": {
      "status": "inside",
      "bounds": {
        "current": {
          "min": 0.01,
          "max": 100,
          "unit": "A"
        },
        "copperWeight": {
          "min": 0.5,
          "max": 4,
          "unit": "oz"
        },
        "tempRise": {
          "min": 1,
          "max": 100,
          "unit": "°C"
        },
        "traceLength": {
          "min": 1,
          "max": 10000,
          "unit": "mm"
        },
        "isExternal": {
          "min": 0,
          "max": 1,
          "unit": ""
        },
        "traceWidth": {
          "min": 0.01,
          "max": 100,
          "unit": "mm"
        },
        "boardThickness": {
          "min": 0.2,
          "max": 6,
          "unit": "mm"
        },
        "planeDistance": {
          "min": 0,
          "max": 6,
          "unit": "mm"
        },
        "planeCopperWeight": {
          "min": 0.5,
          "max": 2,
          "unit": "oz"
        },
        "standard": {
          "min": 0,
          "max": 1,
          "unit": ""
        }
      },
      "outside": [],
      "model": {
        "description": "IPC-2152 Figure 5-1 through I = 0.024·ΔT^0.44·A^0.725, checked against IPC-2221 (1998) Figure 6-4 chart C (the same chart) at 10 to 45 °C and up to 700 sq mil: the cross-section is within −3.5 % to +4.4 % of 12 chart readings, and 11.3 % short at 10 °C and 700 sq mil",
        "worstCaseError": 0.12,
        "inside": true
      },
      "models": [
        {
          "description": "IPC-2152 Figure 5-1 through I = 0.024·ΔT^0.44·A^0.725, checked against IPC-2221 (1998) Figure 6-4 chart C (the same chart) at 10 to 45 °C and up to 700 sq mil: the cross-section is within −3.5 % to +4.4 % of 12 chart readings, and 11.3 % short at 10 °C and 700 sq mil",
          "worstCaseError": 0.12,
          "inside": true
        },
        {
          "description": "rftools thermal model (board-specific), a closed-form thermal network fitted to rftools' own committed 2-D solver of the trace's cross-section: Width 0.25–5.1 mm (internal from 1.27 mm), copper ½–3 oz, board 1.4–3.2 mm, a plane from 0.1 mm under the trace to where it fits, plane copper ½–2 oz, rise 5–100 °C, ambient 0–85 °C (the rise before the margin). Inside that range its rise is within 2.81 % of 3,168 solver results",
          "worstCaseError": 0.029,
          "inside": true
        }
      ]
    },
    "computedAt": "2026-09-24T14:05:11.003Z",
    "inputs": {
      "current": 1,
      "copperWeight": 1,
      "tempRise": 10,
      "traceLength": 100,
      "isExternal": 1,
      "traceWidth": 0.5,
      "boardThickness": 1.6,
      "planeDistance": 0,
      "planeCopperWeight": 0.5,
      "standard": 0
    },
    "seed": null,
    "elapsedSeconds": 0.003
  }
}

{
  "detail": [
    {
      "type": "float_parsing",
      "loc": [
        "body",
        "inputs",
        "current"
      ],
      "msg": "Input should be a valid number, unable to parse string as a number",
      "input": "abc"
    }
  ]
}

Una entrada enviada como texto. No se contó nada.

{
  "detail": "More than 120 requests in 60 seconds from this address.",
  "errorKind": "rate_limited",
  "limit": 120,
  "windowSeconds": 60,
  "upgradeUrl": "https://rftools.io/pricing/"
}

Demasiadas solicitudes en un minuto, con Retry-After.

Las mismas entradas en la página de la calculadoraCalculadora de Ancho de Pista PCB por Corriente, con estos valores