Semiconductor JFET Pinch Off Voltage Calculator
Explicit symmetric JFET half-channel depletion pinch-off potential separates built-in from external magnitude; not BJT total punch-through voltage or operating bias instruction.
Description
A symmetric JFET depletion model uses the half-channel width to estimate pinch-off potential.
A symmetric JFET depletion model uses the half-channel width to estimate pinch-off potential.1
Subtracting built-in potential separates the model total from its signed external contribution.
When to use Semiconductor JFET Pinch Off Voltage Calculator
Use this tool when you need to calculate the stated measurement summary or conditional model from matched observations. Prepare independently matched device or specimen measurements, units, branch selection, and model or calibration conventions.
How to use Semiconductor JFET Pinch Off Voltage Calculator and understand its results
- Prepare independently matched device or specimen measurements, units, branch selection, and model or calibration conventions.
- Enter callerChannelDopantPerM3, observedChannelHalfWidthM, callerPermittivityFM, callerElementaryChargeC, observedBuiltInPotentialV, following the field table and calculation rules below, then run the tool.
- Read modeledJfetTotalPinchOffPotentialV, modeledExternalPinchOffMagnitudeV. Use the output table and calculation rules below to interpret units, signs, crossings, and flags.
- Correct any input issues and run again. Before using a successful result, review its units, signs, evidence coverage, and stated model or reference assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| callerChannelDopantPerM3 | Caller channel dopant per m3 | number | Required |
| observedChannelHalfWidthM | Observed channel half width m | number | Required |
| callerPermittivityFM | Caller permittivity f m | number | Required |
| callerElementaryChargeC | Caller elementary charge c | number | Required |
| observedBuiltInPotentialV | Observed built in potential v | number | Required |
Require positive dopant density, half-width, permittivity, and charge, with nonnegative built-in potential. Compute qNa²/(2ε), then subtract built-in potential. The output named magnitude can be negative; no absolute value or clipping is applied.
Vtotal=q×N×halfWidth²/(2ε); Vexternal=Vtotal−VbuiltIn Read these symbols with the field meanings and branch or reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| modeledJfetTotalPinchOffPotentialV | Modeled JFET total pinch off potential v | number |
| modeledExternalPinchOffMagnitudeV | Modeled external pinch off magnitude v | number |
{
"input": {
"callerChannelDopantPerM3": 1e+22,
"observedChannelHalfWidthM": 0.000001,
"callerPermittivityFM": 1e-10,
"callerElementaryChargeC": 1.6e-19,
"observedBuiltInPotentialV": 0.5
},
"output": {
"modeledJfetTotalPinchOffPotentialV": 8,
"modeledExternalPinchOffMagnitudeV": 7.5
}
}Limitations and assumptions
Measurements, branch identification, units, and model applicability must be independently established. Results do not supply universal material constants, a complete physical model, or operating-condition approval.
Missing required fields, unknown fields, wrong types, and violated calculation rules return input issues. Numeric values must be finite; nonfinite numeric outputs are rejected.
Alternative or Complementary methods
For a related task, use Semiconductor MESFET Threshold Voltage Calculator: A one-sided Schottky depletion model balances built-in voltage against channel depletion potential. Uniform doping and the stated channel-thickness convention are assumptions supplied for this MESFET threshold calculation. For a complementary step, use Semiconductor HEMT Threshold Voltage Calculator: A HEMT sheet-charge threshold budget combines band alignment with barrier capacitance per area. Signed charge and alignment conventions must be independently matched to the heterostructure model.
References
Similar or alternative tools
- Semiconductor MESFET Threshold Voltage Calculator
A one-sided Schottky depletion model balances built-in voltage against channel depletion potential. Uniform doping and the stated channel-thickness convention are assumptions supplied for this MESFET threshold calculation.
- Semiconductor HEMT Threshold Voltage Calculator
A HEMT sheet-charge threshold budget combines band alignment with barrier capacitance per area. Signed charge and alignment conventions must be independently matched to the heterostructure model.