Digital Isolators Handle The Rads In Small Satellites

According to Renesas Electronics, its tw- plastic packaged, radiation-tolerant digital isolators provide the highest isolation protection (2,500VRMS) from high voltage spikes in power supply stages and serial communications interfaces used in low Earth orbit (LEO) Small Satellites (SmallSats).

 

The passive input ISL71610M and active input ISL71710M offer notable performance across specs that include isolation voltage, data rate, common mode transient immunity, propagation delay, quiescent current, and dynamic current. The company’s Giant Magneto Resistive (GMR) digital isolators are viable replacements for optocouplers that are susceptible to cloudy optics from total ionizing dose (TID) radiation. Both GMR isolators are also said to out-perform transformer-based digital isolators that experience electromagnetic interference (EMI) due to radiated emissions from edge and dipole radiation. They are characterization tested at a TID up to 30 krads (Si), and for single event effects at a linear energy transfer of 43MeV•cm2/mg.  

 

In isolation partitioned power supply designs, the ISL71610M and ISL71710M provide an instantaneous 2.5 kVRMS of isolation and 600 VRMS continuous working voltage at 85°C. In serial communications subsystems that need the transmitter and receiver electrically isolated from each other, the ISL71610M operates up to 100 Mb/s, and the ISL71710M up to 150 Mb/s.

 

ISL71610M and ISL71710M features include:

  • Supply range of 3V to 5.5V
  • Isolation voltage of 2.5kVRMS for 1 minute, and 600VRMS continuous
  • Data rates up to 100Mbps (ISL71610M), and 150Mbps (ISL71710M)
  • Common mode transient immunity of 20kV/µs (ISL71610M), and 50kV/µs (ISL71710M)
  • Propagation delay of 8ns (ISL71610M), and 10ns (ISL71710M)
  • Quiescent current of 1.3mA (ISL71610M), and 1.8mA (ISL71710M)
  • Full military temperature range operation
  • TA = -55°C to +125°C
  • TJ = -55°C to +150°C
  • Radiation characterization at Low Dose Rate (LDR) (0.01rad (Si)/s): 30krad (Si)
  • SEE characterization: No SEB/SEL, VDD = 7V; LET = 43MeV•cm2/mg

The ISL71610M and ISL71710M are available now in 8-lead 5 mm x 4 mm SOIC packages. The passive input ISL71610M is priced at $61.53 each/1,000, and the active input ISL71710M is priced at $64.18 each/1,000. For more information checkout the ISL71610M and ISL71710M datasheets.