Radiation-tolerant PWM controller and GaN FET driver for new space smallsats

Renesas Electronics Corporation has released what is claimed to be the space industry’s first plastic-packaged, radiation-tolerant PWM controller and GaN FET driver for DC-DC power supplies in smallsats and launch vehicles. The ISL71043M single-ended current mode PWM controller and the ISL71040M low-side GaN FET driver are excellent for isolated flyback and half-bridge power stages, and motor control driver circuits in satellite buses and payloads. Private ‘new space’ companies have started launching smallsats to form large constellations working in multiple low Earth orbit planes. Smallsat mega-constellations offer global broadband Internet links, plus high-resolution Earth observation imaging for air, sea, and land asset tracking. The PWM controller gives fast signal propagation and output switching in a small 4mm x 5mm SOIC plastic package, decreasing PCB area up to 3x compared to competitive ceramic packages. Also, the device’s 5.5mA max supply current decreases power loss more than 3x, and its adjustable operating frequency – up to 1MHz – allows higher efficiency and the use of smaller passive filter components. Both devices are characterization tested at a TID of up to 30krads(Si), and for single event effects at a linear energy transfer of 43MeV•cm2/mg. Both devices work over an extended temperature range of -55C to +125C. “The ISL71043M and ISL71040M along with our GaN FETs and digital isolators give customers a size and cost optimised power supply solution for large constellations of smallsats,” said Philip Chesley, vice president, Industrial Analog and Power Business Division, Renesas Electronics Corporation. “Renesas’ radiation-tolerant plastic package flow and cutting-edge IC technology provides the optimal cost and radiation performance new space customers demand for five-year mission profiles in low Earth orbit.”