Satnews Daily
November 16th, 2016

Highly Tolerant Is Microsemi

According to Euroconsult's 2015 report "Satellites to Be Built & Launched by 2024" 60 percent more satellites will be launched by 2024 versus the past decade, the increase driven primarily by civilian government agencies as established space countries replace and expand their on orbit satellite systems and more countries acquire their first operational satellite systems.

The technology that produces satellites is highly complex—to bring their expertise into this spatial world, Microsemi Corporation (Nasdaq: MSCC) is now sampling their LX7720 radiation-tolerant motor controller, the newest member of the firm's Space System Manager (SSM) product family.

As the industry's first highly integrated radiation-tolerant motor control integrated circuit (IC), the LX7720 significantly reduces weight and board space relative to conventional discrete motor control circuits, offering a unique solution for satellite manufacturers sensitive to area and weight challenges.
Microsemi's SSM product family of special purpose mixed signal devices leverages the company's more than 50 years of space heritage and provides its customers with innovative space system solutions solving application-specific challenges. As the second member of the SSM family, joining the previously announced LX7730 radiation-tolerant telemetry controller IC, the new LX7720 works with a field programmable gate array (FPGA) and complements Microsemi's other components specifically designed for the demanding space market.

The LX7720 has already been adopted by customers to enable various motor control applications in space robotics and human-rated space programs. Additional target applications for the device include motor driver servo control, linear actuator servo control and driving stepper, brushless direct current (BLDC), and permanent-magnet synchronous (PMSM) motors. These motors can be found on satellite busses (solar panel deployment and driving reaction wheels), on spacecraft payload instruments (multi-axis pointing mechanisms for antennas and laser terminals; precise motion control of lenses, filters, and mirrors), and in robotics applications (pressure-sensitive motion control).
According to Dorian Johnson, the product line manager for Microsemi's analog mixed signal space products, as the reduction of weight and board space on satellites continues to challenge the aerospace market, Microsemi has reinforced their commitment to developing innovative solutions, as is demonstrated with this highly reliable radiation-tolerant motor controller. The company's ever-growing space product portfolio continues to maximize the amount of Microsemi content on sophisticated satellites.

The key features of the LX7720 include:

  • Four half-bridge N-channel MOSFET drivers
  • Four floating differential current sensors
  • Pulse modulated resolver transformer driver
  • Three differential resolver sense inputs
  • Six bi-level logic inputs
  • Fault detection
  • Radiation-tolerant: 100 krad total ionization dose (TID), 50 krad enhanced low dose radiation sensitivity (ELDRS) and single event immune
  • Power drivers via external field-effect transistors (FETs)
  • Loop control electronics for voltage or current control
  • Position read-back (resolver, potentiometer, limit switches, etc.)
  • Highest integration solution
  • Development board available to work with company's RTG4™ FPGA Development Kit