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Aumento da temperatura do traço de PCB

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

Slug pcb-trace-temp. Calcule o aumento de temperatura de trilhas de cobre em PCB sob corrente de carga com o ajuste do IPC-2221 para camadas externas. Insira largura, espessura e corrente para obter ΔT acima da temperatura ambiente. Gratuito, resultados instantâneos.

Entradas

Envie cada uma destas em inputs, nas unidades mostradas. A maioria é obrigatória: uma chamada sem alguma delas é recusada (400) e não custa nada; uma entrada que a calculadora dispensa assume o padrão mostrado. Uma entrada fora da sua faixa ainda é calculada e sinalizada na procedência.

Entradas de pcb-trace-temp
Nome	Unidade	Faixa	Padrão	Descrição
currentnúmero	A	no mínimo 0	3	Corrente
traceWidthnúmero	mm	no mínimo 0.1	2	Largura da trilha
copperWeightnúmero	oz	no mínimo 0.5	1	Peso do cobre
ambientTempnúmero	°C	qualquer	25	Temperatura ambiente
traceLengthnúmero	mm	no mínimo 1	100	Comprimento da trilha
boardThicknessnúmero	mm	0.2 … 6	1.6	A espessura da placa inteira. Só o aumento para esta placa (modelo térmico do rftools) a usa; o modelo é validado de 1,4 a 3,2 mm
planeDistancenúmero	mm	0 … 6	0	O dielétrico entre a trilha e o plano de cobre contínuo mais próximo abaixo dela; 0 significa sem plano. Só o aumento para esta placa o usa
planeCopperWeightnúmero	oz	0.5 … 2	0.5	O peso do cobre desse plano (35 µm por onça). Só o aumento para esta placa o usa, e só quando há um plano
isExternalnúmero	nenhuma	0 … 1	1	Muda apenas o aumento específico da placa; o aumento da IPC-2221 é sempre o do gráfico A, externo, e a Figura 5-1 é a mesma em qualquer camadaUm de: 1 Camada externa (superficial) · 0 Camada interna
laminatenúmero	nenhuma	0 … 3	0	O laminado e a espessura dielétrica total da placa, que definem sua temperatura máxima de operaçãoUm de: 0 FR-4, ≥ 0,4 mm · 1 FR-4, 0,1–0,4 mm · 2 Poliimida, ≥ 1,6 mm · 3 Poliimida, 0,1–1,6 mm
standardnúmero	nenhuma	0 … 1	0	O gráfico em que o aumento é lido: a curva externa da IPC-2221A, como em Aumento de temperatura, ou o gráfico conservador da IPC-2152. Em ambos os casos, o limite é a temperatura máxima de operação do laminado menos a temperatura ambiente.Um de: 0 IPC-2221A Fig. 6-4 · 1 IPC-2152 Fig. 5-1

Saídas

Devolvidas em values, pelo nome. Um valor ilimitado ou indefinido é null.

Saídas de pcb-trace-temp
Campo	Unidade	Descrição
tempRiseprincipal	°C	Aumento de temperatura (IPC-2221)
maxTemp	°C	Temperatura máxima da trilha (IPC-2221)
traceResistance	mΩ	Resistência da trilha
powerDissipated	mW	Potência dissipada
currentCapacity	A	Capacidade de corrente (IPC-2221, ΔT = 10 °C)
tempRise2152	°C	Aumento de temperatura (IPC-2152 Fig. 5-1)
maxTemp2152	°C	Temperatura máxima da trilha (IPC-2152 Fig. 5-1)
inChartRange	nenhuma	Dentro da faixa da IPC-2152 Fig. 5-1
tempRiseBoard	°C	Aumento de temperatura (esta placa, modelo térmico)
maxTempBoard	°C	Temperatura máxima da trilha (esta placa, modelo térmico)
inModelRange	nenhuma	Dentro da faixa do modelo térmico
chartRise	°C	Aumento da temperatura no gráfico
limitRise	°C	Aumento permitido
limitPercent	%	Porcentagem do limite
minTraceWidth	mm	Largura para conformidade
maxCurrent	A	Corrente para conformidade

Como chamar

Calcular: uma chamada, a requisição e a resposta completas, e os seus erros.
Lote: esta calculadora com outras, ou uma varredura, em uma requisição.
Resolver para um valor-alvo: o valor de uma entrada que leva uma saída a um alvo.

curl -X POST https://rftools.io/api/py/v1/calculate \
  -H "X-API-Key: $RFTOOLS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "slug": "pcb-trace-temp",
    "inputs": {
      "current": 3,
      "traceWidth": 2,
      "copperWeight": 1,
      "ambientTemp": 25,
      "traceLength": 100,
      "boardThickness": 1.6,
      "planeDistance": 0,
      "planeCopperWeight": 0.5,
      "isExternal": 1,
      "laminate": 0,
      "standard": 0
    }
  }'

import rftools

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

result = client.calculate("pcb-trace-temp", {
    "current": 3,
    "traceWidth": 2,
    "copperWeight": 1,
    "ambientTemp": 25,
    "traceLength": 100,
    "boardThickness": 1.6,
    "planeDistance": 0,
    "planeCopperWeight": 0.5,
    "isExternal": 1,
    "laminate": 0,
    "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": "pcb-trace-temp",
    "inputs": {
      "current": 3,
      "traceWidth": 2,
      "copperWeight": 1,
      "ambientTemp": 25,
      "traceLength": 100,
      "boardThickness": 1.6,
      "planeDistance": 0,
      "planeCopperWeight": 0.5,
      "isExternal": 1,
      "laminate": 0,
      "standard": 0
    }
  }),
});
console.log(response.status, await response.json());

package main

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

func main() {
	body := []byte(`{
	  "slug": "pcb-trace-temp",
	  "inputs": {
	    "current": 3,
	    "traceWidth": 2,
	    "copperWeight": 1,
	    "ambientTemp": 25,
	    "traceLength": 100,
	    "boardThickness": 1.6,
	    "planeDistance": 0,
	    "planeCopperWeight": 0.5,
	    "isExternal": 1,
	    "laminate": 0,
	    "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": "pcb-trace-temp",
  "values": {
    "tempRise": 5.342104787621994,
    "maxTemp": 30.342104787621995,
    "traceResistance": 24.63054187192118,
    "powerDissipated": 221.67487684729062,
    "currentCapacity": 3.953008949362809,
    "chartRise": 5.342104787621994,
    "limitRise": 105,
    "limitPercent": 5.0877188453542805,
    "minTraceWidth": 0.3281129167384957,
    "maxCurrent": 11.12374665416563,
    "tempRise2152": 25.814961619314374,
    "maxTemp2152": 50.814961619314374,
    "inChartRange": 1,
    "tempRiseBoard": 10.281805774783722,
    "maxTempBoard": 35.28180577478372,
    "inModelRange": 1
  },
  "warnings": [],
  "errors": [],
  "provenance": {
    "method": "calculator:pcb-trace-temp",
    "version": "api@3f2c1a9b04de",
    "formulaRef": "IPC-2221A (May 2003) §6.2, Figure 6-4, chart A (the chart of IPC-2221, February 1998), through its published fit; IPC-2152 (August 2009) §5, Figure 5-1; the board-specific rise: 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-external-fit",
        "text": "The IPC-2221 rise is IPC-2221 Figure 6-4 chart A, the external-layer chart, through its published fit with k = 0.048; chart A draws 10 to 100 °C up to 700 sq mil, and the internal-layer chart is not applied to this rise."
      },
      {
        "code": "ipc-2152-figure-5-1",
        "text": "The IPC-2152 rise 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; IPC-2152’s corrections for board thickness and a nearby copper plane are not applied."
      },
      {
        "code": "copper-weight",
        "text": "Copper is 35 µm thick per ounce, and the trace cross-section is a rectangle of that thickness."
      },
      {
        "code": "resistance-at-20c",
        "text": "The trace resistance and power use ρ = 1/58 Ω·mm²/m (IEC 60028, 1.7241×10⁻⁸ Ω·m) at 20 °C, not corrected for the trace’s temperature."
      },
      {
        "code": "thermal-model-own-method",
        "text": "The board-specific rise 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 rise includes a 15 % margin for the model's measured disagreement with published data: it is 1.15 times the model's rise."
      },
      {
        "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 rise is computed at the ambient entered: it sets the air’s properties, the radiation and the copper’s resistivity, so a hotter ambient gives a somewhat larger rise."
      },
      {
        "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 rise 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 rise is the one to use there."
      }
    ],
    "validRange": {
      "status": "inside",
      "bounds": {
        "current": {
          "min": 0,
          "max": null,
          "unit": "A"
        },
        "traceWidth": {
          "min": 0.1,
          "max": null,
          "unit": "mm"
        },
        "copperWeight": {
          "min": 0.5,
          "max": null,
          "unit": "oz"
        },
        "ambientTemp": {
          "min": null,
          "max": null,
          "unit": "°C"
        },
        "traceLength": {
          "min": 1,
          "max": null,
          "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"
        },
        "isExternal": {
          "min": 0,
          "max": 1,
          "unit": ""
        },
        "laminate": {
          "min": 0,
          "max": 3,
          "unit": ""
        },
        "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 rise is within −5.7 % to +7.3 % of 12 chart readings, and 18 % low at 10 °C and 700 sq mil",
        "worstCaseError": 0.18,
        "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 rise is within −5.7 % to +7.3 % of 12 chart readings, and 18 % low at 10 °C and 700 sq mil",
          "worstCaseError": 0.18,
          "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": 3,
      "traceWidth": 2,
      "copperWeight": 1,
      "ambientTemp": 25,
      "traceLength": 100,
      "boardThickness": 1.6,
      "planeDistance": 0,
      "planeCopperWeight": 0.5,
      "isExternal": 1,
      "laminate": 0,
      "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"
    }
  ]
}

Uma entrada enviada como texto. Nada foi contabilizado.

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

Requisições demais em um minuto, com Retry-After.

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