The **M5R65RH-R** is a high-performance, radiation-hardened (Rad-Hard) power MOSFET designed primarily for aerospace, defense, and satellite applications. It belongs to the STMicroelectronics family of radiation-hardened N-channel power transistors. --- ### 1. Key Technical Specifications Below are the primary electrical characteristics of the M5R65RH-R: | Parameter | Symbol | Value | | :--- | :--- | :--- | | **Drain-Source Voltage** | $V_{DS}$ | 650 V | | **Continuous Drain Current** | $I_D$ | 22 A (at 25°C) | | **Static Drain-Source On-Resistance** | $R_{DS(on)}$ | 0.17 $\Omega$ (typ) | | **Total Gate Charge** | $Q_g$ | 48 nC | | **Package Type** | - | TO-254 / Flat-Pack / Die | --- ### 2. Electronic Architecture and Design The device is built using advanced **Super-Junction technology**. Unlike standard MOSFETs, super-junction structures allow for a significant reduction in on-resistance ($R_{DS(on)}$) while maintaining a high breakdown voltage ($BV_{DSS}$). #### Key Internal Components: * **N-Channel Enhancement Mode:** It is a "normally-off" device, requiring a positive gate voltage to conduct. * **Intrinsic Body Diode:** Includes a fast-recovery body diode, which is crucial for power conversion circuits to handle inductive energy. * **Gate Protection:** Often includes internal structures to stabilize the gate oxide against transient spikes. --- ### 3. Radiation Hardness Features What sets the "RH" (Radiation Hardened) version apart from commercial MOSFETs is its ability to survive extreme space environments: * **Total Ionizing Dose (TID):** Guaranteed to withstand high levels of radiation (typically up to 100 krad or more) without significant threshold voltage shift. * **Single Event Effects (SEE):** Designed to be immune to Single Event Burnout (SEB) and Single Event Gate Rupture (SEGR) caused by heavy ions. * **SEB/SEGR Immunity:** Tested to Linear Energy Transfer (LET) levels relevant for Geostationary (GEO) or Low Earth Orbit (LEO) missions. --- ### 4. Application Use Cases The M5R65RH-R is typically integrated into the following systems: 1. **DC-DC Converters:** High-efficiency power supply modules for satellites. 2. **Motor Controllers:** Driving actuators in robotic arms or satellite positioning systems. 3. **Power Distribution Units (PDU):** Managing electrical loads from solar arrays to batteries. 4. **Resonant Converters:** Utilizing the low gate charge for high-frequency switching to reduce the size of passive components. --- ### 5. Schematic Symbol Representation ```text Drain (D) | | +-----+-----+ | | | | | --+-- | (Body Diode) Gate| | ^ | | | (G) | | | | | | | | --+-- | +-----+-----+ | | Source (S) ```