Infineon IR HiRel continues to further the frontiers of high-reliability power management with the introduction of the RIC70847, a radiation-hardened (rad-hard) 17.1 V buck controller featuring integrated gate drivers. As next-generation space missions shift to more advanced and complex systems, the need for robust, efficient and reliable power conversion has become increasingly critical. The RIC70847 is engineered to address these challenges, delivering a unique blend of advanced control features and qualified radiation hardness in a compact, integration-friendly design.
KEY FEATURES AND CAPABILITIES
Figure 1 RIC70847 is offered in a hermetically sealed 24-pin flatpack package.
At the heart of the RIC70847’s appeal is its wide input voltage range, which supports 5 and 12 V inputs, providing designers with the flexibility to accommodate varying power architectures and supply rails commonly encountered in satellite constellations, deep space probes and advanced avionics. This capability is especially important as modern spacecraft increasingly deploy distributed power systems and digital payloads that require precise, stable voltage rails for FPGAs, ASICs, DSPs and sensitive instrumentation.
The RIC70847, shown in Figure 1, incorporates a highly accurate voltage reference to ensure that the output voltage remains accurate and stable even in the harshest operating conditions. This reference is designed to maintain tight regulation not only across a broad temperature range but also under significant radiation exposure — critical for long-duration missions operating in extreme environmental conditions. The device operates over the full ambient temperature range of -55°C to +125°C.
Transient response is another area where power converters can make or break system performance, especially when supporting fast-switching loads. The RIC70847 addresses this with optional load line regulation (LLR), a feature that enhances transient performance and minimizes voltage swings when loads change rapidly, as shown in Figure 2.
Figure 2 Output voltage regulation accuracy with and without LLR overload at 500 kHz and VOUT = 1.0 V at VIN = 5 V and VIN = 12 V, L = 270 nH, Cout = -5,637 µF.
The advanced LLR is particularly beneficial for applications such as space-grade FPGA, ASIC and DSP core rails, where stringent voltage tolerances must be met during dynamic operation. By optimizing the converter’s output impedance, designers can tailor load line characteristics to match specific application requirements, thus improving overall system stability and performance.
Control precision and flexibility are hallmarks of the RIC70847. The device utilizes fixed-frequency peak-current mode control to enable predictable switching behavior, robust noise immunity and fast transient response. This control scheme simplifies compensation, reduces susceptibility to subharmonic oscillations with user-adjustable slope compensation and enables accurate current sharing in multi-phase implementations. To further optimize performance, the RIC70847 offers a wide programmable range of switching frequencies. This allows engineers to strike the ideal balance between solution size and efficiency: higher frequencies can minimize the size of passive components and board footprint, while lower frequencies improve efficiency by reducing switching losses — an essential consideration when thermal management and energy budgets are tightly constrained.
Another key advantage is the RIC70847’s low minimum on-time, which enables high step-down voltage ratios. This feature is particularly valuable in systems where core voltages are trending lower, but input voltages remain relatively high — such as when deriving low-voltage rails for cutting-edge digital processing units from standard satellite bus voltages. The ability to achieve substantial voltage step-downs without compromising efficiency or control accuracy is a significant benefit for designers supporting next-generation payloads and compute-intensive applications.
STREAMLINED DESIGN
Integration is at the forefront of Infineon’s design philosophy, and the RIC70847 exemplifies this with its integrated half-bridge gate driver. By embedding the gate driver, the controller reduces the need for external components, streamlines PCB layout and improves overall system reliability. Fewer external parts mean less potential for failure, lower bill-of-materials cost and easier qualification. This half-bridge gate driver is engineered to work with logic-level FETs, such as Infineon’s HiRel R8 rad-hard power FETs.
Ruggedness and safety are equally prioritized in the design of RIC70847. The device incorporates comprehensive integrated fault protections, including under-voltage lockout, overcurrent protection (OCP) and thermal shutdown. These safeguards protect both the controller and downstream circuitry from potentially damaging conditions, adding vital layers of security for mission-critical systems. Additionally, the integrated programmable soft start feature allows system designers to control inrush current at startup, ensuring a gentle ramp-up and preventing voltage overshoot that could threaten sensitive loads.
RELIABILITY AND QUALIFICATION
The RIC70847 is radiation hardened by design, a defining advantage of the device. The device has a total ionizing dose radiation lot acceptance testing rating of 100 krad (Si). This level of protection ensures that the controller can operate reliably under prolonged radiation exposure, such as that encountered in geosynchronous orbit, deep space or during solar events. Furthermore, the RIC70847 is hardened against single event effects, with no single event burnout or latch-up observed up to a linear energy transfer of 81.8 MeV·cm2/mg. Single event transients have also been characterized up to this level, providing additional confidence in the controller’s resilience to sporadic high-energy particle strikes.
Infineon’s commitment to reliability is further demonstrated by the RIC70847’s qualification and screening to MIL-PRF-38535, Class V, with Defense Logistics Agency certification pending. This ensures that each unit consistently meets stringent standards for performance, screening and traceability, making it suitable for the most demanding space applications where failure is not an option.
POWERING MODERN APPLICATIONS
The RIC70847 is ideally suited for a wide range of power management applications. As a point-of-load converter, illustrated in Figure 3, it is perfect for supplying core rails to space-grade FPGA, ASIC and DSP devices — components that are the backbone of modern digital processing payloads. Its robust feature set and flexibility also make it an excellent choice for distributed satellite power systems, where reliability, efficiency and compact design are essential. Whether enabling sophisticated payloads in next-generation satellites or supporting critical avionics in high-altitude aircraft, the RIC70847 delivers the performance, protection and reliability required for mission success.
Figure 3 Typical Point-of-Load (PoL) application block diagram.
SUMMARY AND SAMPLES
Infineon HiRel’s RIC70847 stands as a new benchmark in radiation hardened power management for space platforms. Its comprehensive array of control, protection and integration features, paired with top radiation hardness and rigorous qualification, enables system designers to create smaller, more efficient and more reliable power solutions for harsh operational environments. As the demand for space applications continues to grow, the RIC70847 offers robust power delivery for the next-generation of space exploration.
IR HiRel, an Infineon Technologies company
Leominster, Mass.
www.infineon.com/products/high-reliability
hirel-discretes@infineon.com