Highly Integrated, Radiation-Hardened Motor Controller for Motor Control and Position Sensing Circuitry of Satellite Elements

Published  October 27, 2020   0
LX7720 Radiation-Hardened Motor Controller from Microchip

Microchip Technology has made the latest addition to its Space System Manager (SSM) product family with the introduction of highly integrated radiation-hardened by design (RHBD) motor control integrated circuit (IC), LX7720. Combining more than 20 functions into a single chip, this IC significantly reduces weight and board space relative to conventional discrete motor control circuits.

The LX7720 offers radiation tolerance to 100 krad Total Ionization Dose (TID), 50 krad to Enhanced-Low-Dose-Rate-Sensitivity (ELDRS) exposure, and is single event immune. It serves as a mixed-signal companion IC to the selected digital IC used in the application.

The LX7720 controller comes with four half-bridge N-channel Metal Oxide Semiconductor Field Effect Transistor (MOSFET) drivers, four floating differential current sensors, a pulse modulated resolver transformer driver, three differential resolver sense inputs. Other than these, the IC integrates six bi-level logic inputs, power drivers via external Field Effect Transistors (FETs), loop control electronics for voltage or current control, position read-back (resolver, potentiometer, limit switches, etc.), fault detection, etc. all in a single device.
Ideal for spacecraft applications involving motor driver servo control, linear actuator servo control, and for driving stepper, brushless direct current (BLDC), and permanent-magnet synchronous (PMSM) motors, the LX7720 is available in MIL-PRF-38535 Class Q and V flows packaged in a 132-pin hermetic ceramic quad flatpack and a sub-QML screened option in a 208-pin plastic package. Samples and the LX7720-DB development boards are available from the company website.