AIDT 온디바이스 STEM 초광대역(UWBG) 다이아몬드 MOSFET 극한 전력전자 및 2DHG 서보 엔진

using System;
using System.Runtime.CompilerServices;

namespace ZeliDesk.Stem.DiamondElectronics
{
    public readonly ref struct DiamondMosfetState
    {
        public readonly float DrainCurrentA;
        public readonly float JunctionTempCelsius;
        public readonly float BreakdownMarginPercent;
        public readonly bool IsThermalDeratingActive;

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public DiamondMosfetState(float ids, float tjC, float margin, bool isDerating)
        {
            DrainCurrentA = ids;
            JunctionTempCelsius = tjC;
            BreakdownMarginPercent = margin;
            IsThermalDeratingActive = isDerating;
        }
    }

    public ref struct DiamondMosfetPowerServo
    {
        private const float MaxBreakdownVoltageV = 10000.0f; // 10 kV class
        private const float CriticalJunctionTempC = 550.0f;

        private readonly float _thermalResistanceCPerW;
        private readonly float _channelWidthUm;
        private readonly float _channelLengthUm;

        private float _gateVoltageV;
        private float _junctionTempC;

        public DiamondMosfetPowerServo(
            float rth = 0.8f, 
            float widthUm = 1000.0f, 
            float lengthUm = 2.0f)
        {
            _thermalResistanceCPerW = MathF.Max(0.1f, rth);
            _channelWidthUm = MathF.Max(10.0f, widthUm);
            _channelLengthUm = MathF.Max(0.5f, lengthUm);
            _gateVoltageV = -5.0f; // Normally-on 2DHG p-channel default
            _junctionTempC = 25.0f;
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public DiamondMosfetState StepPowerControl(
            float vdsVolts, 
            float commandCurrentA, 
            float ambientTempC, 
            float dt)
        {
            // 1. Mobility temperature dependence: mu(T) = mu0 * (T / 300)^-1.8
            float tempKelvin = _junctionTempC + 273.15f;
            float tempRatio = tempKelvin / 300.0f;
            float mobilityFactor = MathF.Pow(tempRatio, -1.8f);

            // 2. Maximum drain current at full saturation
            float vth = 2.0f; // Threshold voltage
            float vgt = MathF.Abs(_gateVoltageV - vth);
            float maxCurrentA = 0.05f * (_channelWidthUm / _channelLengthUm) * mobilityFactor * (vgt * vgt);

            float actualCurrentA = MathF.Min(commandCurrentA, maxCurrentA);

            // 3. Power dissipation & Junction temperature: Tj = Tamb + P * Rth
            float pDissW = actualCurrentA * vdsVolts;
            float targetTj = ambientTempC + (pDissW * _thermalResistanceCPerW);
            _junctionTempC += (targetTj - _junctionTempC) * MathF.Min(1.0f, dt * 50.0f); // Thermal response

            // 4. Breakdown margin
            float breakdownMargin = ((MaxBreakdownVoltageV - vdsVolts) / MaxBreakdownVoltageV) * 100.0f;
            bool isDerating = _junctionTempC > (CriticalJunctionTempC - 50.0f);

            // Active gate clamping if overheating
            if (isDerating)
            {
                _gateVoltageV += 5.0f * dt; // Reduce gate drive towards pinch-off
            }

            return new DiamondMosfetState(actualCurrentA, _junctionTempC, breakdownMargin, isDerating);
        }
    }
}