Microchip Debuts a Radiation-Hardened MOSFET for Space-Based Applications

The M6 MRH25N12U3 from Microchip is intended to enhance the reliability of power supplies in space applications that are under constant threat from extreme particle interactions as well as from solar and electromagnetic events.

The M6 MRH25N12U3. Image courtesy of Microchip

The radiation-hardened M6 MRH25N12U3 MOSFET withstands the harsh environments of space to extend the reliability of power circuitry. The radiation-hardened MOSFET has completed testing for Defense Logistics Agency (DLA) review and qualification, and the unit aims for sourcing in the U.S. military supply chain. JANSR2N7593U3 certification is expected later this month. 
 

The Need for Radiation Hardened Semiconductors

Nanosats aka Cubesats, are tiny, cheap disposable satellites that generally operate in low earth orbit (LEO). A single launch can hurl swarms of devices into space. Because of their multiple redundancy and low expected lifetime, planners generally employ common off the shelf (COTS) semiconductors, which are adequate to the limited needs of Cubesats. But, for multi-million dollar vehicles meant for deep space which have multi-year life expectancies, radiation protection is a must. 

According to Leon Gross, vice president of Microchip’s Discrete Product Group business unit, “Microchip’s entry into the radiation-hardened MOSFET market reflects our long-term commitment to support our customer base and provide aerospace and defense OEMs and integrators with high-performance solutions and continuous supply.”  He goes on to say that “In addition to our proven quality and reliability, the M6 MRH25N12U3 provides a value pricing option for developers and offers them full application support.” 
 

Standing up the Challenges of Space

The device can withstand total ionizing dose (TID) up to 100 krad and is resilient in the face of severe single event effects (SEE), with linear energy transfer (LET) up to 87 MeV/mg/cm2. As established through validation tests, there is assurance of 100% wafer lot radiation hardness. 

 

Input

The total input capacitance (Ciss) 1980pF (max). The MOSFET’s maximum gate source threshold voltage, or Vgs(th), is 4 volts (max). The maximum Vgs is ±20 volts

 

Current Carrying Capacity

Drain currents (maximum) for the 250 volt MOSFET are 12.4 amps at 25℃  and 7.8 amps at 100℃. Pulsed drain current 49.6A. If more current capacity is needed, multiple MRH25N12U3 MOSFETs can be paralleled. Each individual device can dissipate 75 watts at 25℃, derating linearly at 0.60 W/°C.

 

Image courtesy of Microchip.

 

Static Electrical Characteristics

Maximum zero-gate voltage drain current (Idss), at a VDS of 200 volts, is 10µA at 25°C and 25 µA at 125°C. Gain-source leakage current (Igss) is specified at a maximum of ±100nA

 

Applications

The M6 MRH25N12U3 MOSFET is designed to provides the primary switching element in space-based power conversion such as:

• Point-of-load (POL) converters
• DC-DC converters
• Motor drives 

 

Physical

• The M6 MRH25N12U3 is available in a 0.400 x 0.296 x 0.112 inch U3 (SMD-0.5) package. The ceramic package is hermetically sealed and weighs 1 gram
• It operates over a junction temperature range of -55 to 150℃

 

Regulatory and Safety Specifications

Screened to the specifications of:

• MIL-PRF-19500
• JANSR2N7593U3 

 

ESD Rating: 

• Class 3B MIL-STD-750, TM 1020