LIBRARY

Analog.Semiconductors.Tests.DiodeForward

Operating-point check for Diode, one case per branch of the defining equation.

The diode hangs directly across an ideal source, so the junction sees exactly Vbias:

i = Ids*(exlin(V/Vt, Maxexp) - 1) + V/R
exlin(x, M) = if x > M then exp(M)*(1 + x - M) else exp(x)

at the default MSL card (Ids = 1e-6, Vt = 0.04, Maxexp = 15, R = 1e8, temperature dependency off):

• Vbias = 0.65 (case1): V/Vt = 16.25, above Maxexp, so the linear continuation. i = 7.35529 A.

• Vbias = -5 (case2): reverse, i = -Ids + V/R = -1.05e-6 A.

• Vbias = 0.4 (case3): V/Vt = 10, so the exponential. i = 0.0220255 A.

This card is leaky — Ids = 1 µA is MSL's default and Vt = 0.04 is not kT/q — so 0.65 V is past the knee at 7.4 A. Case3 exercises the Shockley exponential.

The dummy RC branch supplies the one differential state a transient test needs.

Usage

ElectricalComponents.Analog.Semiconductors.Tests.DiodeForward(Vbias=0.65)

Parameters:

Name	Description	Units	Default value
Vbias	Bias voltage applied across the diode	V	0.65

Behavior

Source

"""
Operating-point check for Diode, one case per branch of the defining equation.

The diode hangs directly across an ideal source, so the junction sees exactly `Vbias`:
```
i = Ids*(exlin(V/Vt, Maxexp) - 1) + V/R
exlin(x, M) = if x > M then exp(M)*(1 + x - M) else exp(x)
```
at the default MSL card (`Ids = 1e-6`, `Vt = 0.04`, `Maxexp = 15`, `R = 1e8`,
temperature dependency off):

  * `Vbias = 0.65` (case1): `V/Vt = 16.25`, above `Maxexp`, so the **linear
    continuation**. `i = 7.35529` A.
  * `Vbias = -5` (case2): reverse, `i = -Ids + V/R = -1.05e-6` A.
  * `Vbias = 0.4` (case3): `V/Vt = 10`, so the **exponential**. `i = 0.0220255` A.

This card is leaky — `Ids = 1 µA` is MSL's default and `Vt = 0.04` is not `kT/q` — so
0.65 V is past the knee at 7.4 A. Case3 exercises the Shockley exponential.

The dummy RC branch supplies the one differential state a transient test needs.
"""
test component DiodeForward
  "Bias level"
  sig = BlockComponents.Sources.Constant(k = Vbias) {
    "Dyad": {"placement": {"diagram": {"x1": 290, "x2": 390, "y1": 220, "y2": 320}}}
  }
  "Bias source"
  vs = ElectricalComponents.Analog.Sources.VoltageSource() {
    "Dyad": {"placement": {"diagram": {"x1": 425, "x2": 525, "y1": 325, "y2": 425}}}
  }
  "Diode under test, default card"
  d = ElectricalComponents.Analog.Semiconductors.Diode() {
    "Dyad": {"placement": {"diagram": {"x1": 35, "x2": 135, "y1": 120, "y2": 220}}}
  }
  "Dummy branch resistor; provides a differential state without loading the diode"
  r_dummy = ElectricalComponents.Analog.Basic.Resistor(R = 1000) {
    "Dyad": {"placement": {"diagram": {"x1": 165, "x2": 265, "y1": 20, "y2": 120}}}
  }
  "Dummy branch capacitor"
  c_dummy = ElectricalComponents.Analog.Basic.Capacitor(C = 1u) {
    "Dyad": {"placement": {"diagram": {"x1": 295, "x2": 395, "y1": 20, "y2": 120}}}
  }
  "Ground reference"
  ground = ElectricalComponents.Analog.Basic.Ground() {
    "Dyad": {"placement": {"diagram": {"x1": 550, "x2": 650, "y1": 430, "y2": 530}}}
  }
  "Bias voltage applied across the diode"
  parameter Vbias::Voltage = 0.65
relations
  initial c_dummy.v = 0
  connect(sig.y, vs.V) {"Dyad": {"edges": [{"S": 1, "M": [{"x": 475, "y": 270}], "E": 2}], "path": {}}}
  connect(vs.p, d.p, r_dummy.p) {
    "Dyad": {
      "edges": [
        {"S": 1, "M": [{"x": 20, "y": 375}], "E": -1},
        {"S": -1, "M": [], "E": 2},
        {"S": -1, "M": [{"x": 20, "y": 70}], "E": 3}
      ],
      "junctions": [{"x": 20, "y": 170}],
      "path": {}
    }
  }
  connect(r_dummy.n, c_dummy.p) {"Dyad": {"edges": [{"S": 1, "M": [], "E": 2}], "path": {}}}
  connect(d.n, c_dummy.n, vs.n, ground.g) {
    "Dyad": {
      "edges": [
        {"S": 1, "M": [{"x": 410, "y": 170}], "E": -1},
        {"S": -1, "M": [], "E": 2},
        {"S": -1, "M": [{"x": 540, "y": 70}], "E": -2},
        {"S": -2, "M": [], "E": 3},
        {"S": -2, "M": [{"x": 600, "y": 375}], "E": 4}
      ],
      "junctions": [{"x": 410, "y": 70}, {"x": 540, "y": 375}],
      "path": {}
    }
  }
metadata {
  "Dyad": {
    "tests": {
      "case1": {
        "stop": 0.01,
        "atol": {"d.i": 0.00001},
        "expect": {"final": {"d.i": 7.3552880946}}
      },
      "case2": {
        "stop": 0.01,
        "params": {"Vbias": -5},
        "atol": {"d.i": 1e-12},
        "expect": {"final": {"d.i": -0.00000105}}
      },
      "case3": {
        "stop": 0.01,
        "params": {"Vbias": 0.4},
        "atol": {"d.i": 1e-9},
        "expect": {"final": {"d.i": 0.0220254698}}
      }
    }
  }
}
end

Flattened Source

"""
Operating-point check for Diode, one case per branch of the defining equation.

The diode hangs directly across an ideal source, so the junction sees exactly `Vbias`:
```
i = Ids*(exlin(V/Vt, Maxexp) - 1) + V/R
exlin(x, M) = if x > M then exp(M)*(1 + x - M) else exp(x)
```
at the default MSL card (`Ids = 1e-6`, `Vt = 0.04`, `Maxexp = 15`, `R = 1e8`,
temperature dependency off):

  * `Vbias = 0.65` (case1): `V/Vt = 16.25`, above `Maxexp`, so the **linear
    continuation**. `i = 7.35529` A.
  * `Vbias = -5` (case2): reverse, `i = -Ids + V/R = -1.05e-6` A.
  * `Vbias = 0.4` (case3): `V/Vt = 10`, so the **exponential**. `i = 0.0220255` A.

This card is leaky — `Ids = 1 µA` is MSL's default and `Vt = 0.04` is not `kT/q` — so
0.65 V is past the knee at 7.4 A. Case3 exercises the Shockley exponential.

The dummy RC branch supplies the one differential state a transient test needs.
"""
test component DiodeForward
  "Bias level"
  sig = BlockComponents.Sources.Constant(k = Vbias) {
    "Dyad": {"placement": {"diagram": {"x1": 290, "x2": 390, "y1": 220, "y2": 320}}}
  }
  "Bias source"
  vs = ElectricalComponents.Analog.Sources.VoltageSource() {
    "Dyad": {"placement": {"diagram": {"x1": 425, "x2": 525, "y1": 325, "y2": 425}}}
  }
  "Diode under test, default card"
  d = ElectricalComponents.Analog.Semiconductors.Diode() {
    "Dyad": {"placement": {"diagram": {"x1": 35, "x2": 135, "y1": 120, "y2": 220}}}
  }
  "Dummy branch resistor; provides a differential state without loading the diode"
  r_dummy = ElectricalComponents.Analog.Basic.Resistor(R = 1000) {
    "Dyad": {"placement": {"diagram": {"x1": 165, "x2": 265, "y1": 20, "y2": 120}}}
  }
  "Dummy branch capacitor"
  c_dummy = ElectricalComponents.Analog.Basic.Capacitor(C = 1u) {
    "Dyad": {"placement": {"diagram": {"x1": 295, "x2": 395, "y1": 20, "y2": 120}}}
  }
  "Ground reference"
  ground = ElectricalComponents.Analog.Basic.Ground() {
    "Dyad": {"placement": {"diagram": {"x1": 550, "x2": 650, "y1": 430, "y2": 530}}}
  }
  "Bias voltage applied across the diode"
  parameter Vbias::Voltage = 0.65
relations
  initial c_dummy.v = 0
  connect(sig.y, vs.V) {"Dyad": {"edges": [{"S": 1, "M": [{"x": 475, "y": 270}], "E": 2}], "path": {}}}
  connect(vs.p, d.p, r_dummy.p) {
    "Dyad": {
      "edges": [
        {"S": 1, "M": [{"x": 20, "y": 375}], "E": -1},
        {"S": -1, "M": [], "E": 2},
        {"S": -1, "M": [{"x": 20, "y": 70}], "E": 3}
      ],
      "junctions": [{"x": 20, "y": 170}],
      "path": {}
    }
  }
  connect(r_dummy.n, c_dummy.p) {"Dyad": {"edges": [{"S": 1, "M": [], "E": 2}], "path": {}}}
  connect(d.n, c_dummy.n, vs.n, ground.g) {
    "Dyad": {
      "edges": [
        {"S": 1, "M": [{"x": 410, "y": 170}], "E": -1},
        {"S": -1, "M": [], "E": 2},
        {"S": -1, "M": [{"x": 540, "y": 70}], "E": -2},
        {"S": -2, "M": [], "E": 3},
        {"S": -2, "M": [{"x": 600, "y": 375}], "E": 4}
      ],
      "junctions": [{"x": 410, "y": 70}, {"x": 540, "y": 375}],
      "path": {}
    }
  }
metadata {
  "Dyad": {
    "tests": {
      "case1": {
        "stop": 0.01,
        "atol": {"d.i": 0.00001},
        "expect": {"final": {"d.i": 7.3552880946}}
      },
      "case2": {
        "stop": 0.01,
        "params": {"Vbias": -5},
        "atol": {"d.i": 1e-12},
        "expect": {"final": {"d.i": -0.00000105}}
      },
      "case3": {
        "stop": 0.01,
        "params": {"Vbias": 0.4},
        "atol": {"d.i": 1e-9},
        "expect": {"final": {"d.i": 0.0220254698}}
      }
    }
  }
}
end

Test Cases

Test Case case1

Test Case case2

Test Case case3

Related

• Examples

• Experiments

• Analyses

• Tests

  • Capacitor

  • Constant

  • Diode

  • Ground

  • Resistor

  • VoltageSource