New Industry Products

EPC Debuts a Radiation-Hardened eGaN FET for Tough Environments

June 25, 2021 by Gary Elinoff

Efficient Power Conversion’s (EPC) new enhancement-mode gallium nitride (eGaN) FET is primed for space based applications

The EPC7014 is the first member of a new family of radiation-hardened eGaN transistors and ICs designed to perform in the most demanding of environments

Image courtesy of EPC
 

The EPC7014

The EPC7014, a member of EPCs growing radiation-hardened (rad-hard) family, is a 60 volt eGaN FET with an RDS(ON) of 340mΩ. It can handle 2.4 amps continuously, 4 amps pulsed, and takes up only 0.9 x 0.9 mm of boardspace. Additionally, the new eGaN FET has a total dose rating of better than 1 Mrad, and SEE immunity for LET is 85 MeV/(mg/cm2). 

 

EPC’s Commitment

The company has announced that members of the new rad-hard family will be available in chip-scale packages, as do members of EPC’s commercial eGaN FET and IC family.  Packaged versions are available from EPC Space.

As per Alex Lidow, CEO, and co-founder of EPC “EPC’s GaN technology enables a new generation of power conversion and motor drives in space operating at higher frequencies, higher efficiencies, and greater power densities than ever achievable before.” He goes on to state that, “We are excited about this technology's ability to provide mission-critical components to the space and high-reliability markets”. 

 

Radiation Hardness

Due to their structure, eGaNs are resistant to single event effects (SEE). This is largely due to the absence of the layers, such as those that exist in MOSFETs, that can trap stray charges between them. Those same layers then provide a ready pathway through which the captured charge can travel to destroy semiconductor structure. Additionally, eGaNs don’t have a metal oxide layer, which can be a source of charge capture. This prevents build up of the total ionizing dose (TID)

This is a very active area of R&D, and the players are keeping their cards close to the vest. The basic takeaway is that, because of their most basic structural nature, eGaNs have some “natural immunity” to radiation, and refinements in the fabrication process will lead to better and better results.

 

Electrical Specifications 

Maximum ratings include:

  • Maximum VDS is 72 volts
  • Maximum gate-source voltages are +7 and -4 volts

 

Thermal Characteristics (typical values):

  • Thermal Resistance, Junction-to-Case (RθJC) is 7.1°C/W
  • Thermal Resistance, Junction-to-Board (RθJB) is 25°C/W
  • Thermal Resistance, Junction-to-Ambient (RθJA) 104 °C/W

 

Dynamic Specifications (typical values):

  • Input Capacitance (CISS) is 16pF
  • Reverse Transfer Capacitance (CRSS) is 0.1pf
  • Output Capacitance (COSS) is 17pF
  • Total Gate Charge (QG) is 142pC
  • Gate to Source Charge  (QGS) is 43pC
  • Gate to Drain Charge (Qgd) is 25pC
  • Source Drain Recovery Charge (Qrr) is zero

Complete specifications for the EPC7014 can be found in the datasheet

 

Applications

  • Power supplies for satellites and mission equipment
  • Motor drives as components of space vehicles
  • Space-based light detection and ranging (LIDAR) for robotics, navigation and docking
  • Ion thrusters used in satellite orientation and positioning
  • Interplanetary propulsion of low-mass autonomous vehicles

 

Physical

  • The EPC7014 operates over a -55 to +150℃ temperature range