The **M5R86RH-R** is a high-performance, radiation-hardened (Rad-Hard) low dropout (LDO) linear voltage regulator. It is specifically designed for aerospace, satellite, and high-reliability defense applications where electronic components are exposed to ionizing radiation. --- ### ## 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Input Voltage Range** | 1.5V to 12V | | **Output Current** | Up to 2.0A | | **Dropout Voltage** | ~300mV at full load | | **Output Voltage Type** | Adjustable (using external resistors) | | **Operating Temperature** | -55°C to +125°C | | **Radiation Hardening** | TID (Total Ionizing Dose) up to 300 krad(Si) | | **Package Type** | Flat-pack or TO-257 (Hermetic seals) | --- ### ## 2. Core Features & Architecture The internal circuitry is engineered to maintain stability and precision under extreme environmental stress. * **Radiation Tolerance:** The "RH" suffix indicates **Radiation Hardened**. It is immune to SEL (Single Event Latch-up) up to a high LET (Linear Energy Transfer) threshold, ensuring the device doesn't "lock up" when hit by heavy ions in space. * **Low Dropout (LDO) Design:** It allows the regulator to operate with a very small difference between input and output voltage, which minimizes power dissipation and heat. * **Soft Start & Protection:** It typically includes internal current limiting and thermal shutdown protection to prevent damage during fault conditions. * **Remote Sensing:** Supports Kelvin sensing to ensure accurate voltage regulation directly at the load, compensating for voltage drops across PCB traces. --- ### ## 3. Typical Application Circuit To use the M5R86RH-R, external capacitors are required for stability, and a voltage divider is used to set the output. ```c // Simplified Logic of Voltage Setting Vout = Vref * (1 + R1 / R2) // Components needed: 1. Cin: Tantalum or Ceramic (Input stability) 2. Cout: Low ESR (Output stability & transient response) 3. R1, R2: Precision resistors for output setting ``` --- ### ## 4. Primary Use Cases Due to its high cost and specialized certification (MIL-PRF-38535), it is rarely found in consumer electronics. Instead, it is used in: * **Satellite Power Buses:** Distributing clean power to FPGAs and Microcontrollers. * **Deep Space Probes:** Where longevity and radiation resistance are critical. * **Launch Vehicles:** Handling high vibration and thermal swings during ascent. ---