PMOS transistor
Shichman–Hodges P-channel MOSFET.
- electrical
- Modelica Standard Library
- 4 ports
- 2 parameters
pmosLibrarySemiconductorsDescription
A P-channel MOSFET using a simplified Shichman–Hodges (level 1) model with a body effect. Drain and source are interchangeable: the higher-potential terminal acts as the source.
The fixed process parameters describe a small integrated device, not a power MOSFET.
Example
Transistor switches A CMOS inverter of an NMOS and a PMOS transistor, and NPN and PNP transistors switching loads.
Also in this example:DC voltageVoltage sensorGroundResistorPulse voltageNMOS transistorNPN transistorPNP transistor
Ports
Conserving terminals 4
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D
Drain.
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G
Gate. Draws no current.
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S
Source.
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B
Bulk (body). Draws no current; it only shifts the threshold. Usually tied to S or the highest potential.
Parameters
-
Width
W0.00002 m≥ 0
Channel width, in meters. Must exceed 2.5 µm, since the effective width is W − 2.5 µm.
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Length
L0.000006 m≥ 0
Channel length, in meters. Must exceed 2.1 µm, since the effective length is L − 2.1 µm.
Equations
us = max(D.v, S.v), uds = min(D.v, S.v) − us, ubs = max(B.v − us, 0) β = Beta · (W + dW) / (L + dL) ugst = (G.v − us − Vt + K2 · ubs) · K5 id = uds / RDS, for ugst ≥ 0 id = −β · uds · (ugst − uds / 2) + uds / RDS, for ugst < uds id = −β · ugst² / 2 + uds / RDS, otherwise Fixed: Beta = 10.5 µA/V², Vt = −1 V, K2 = 0.41, K5 = 0.839, dW = −2.5 µm, dL = −2.1 µm, RDS = 10 MΩ
Implementation
Modelica.Electrical.Analog.Semiconductors.PMOSAssumptions and limitations
- Static model: no capacitances, so no switching transients. No body diode, and no temperature dependence.
See also
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