Infineon’s New EZ USB™ FX2G3

­Embedded designers often face trade-offs between resource-limited microcontrollers and power-hungry application processors. For devices that require sensor data processing and efficient data transmission like cameras, biometric sensors, and portable instruments, a dedicated USB device controller bridges the gap. Infineon’s EZ USB™ FX2G3 USB 2.0 controller offers the ideal balance of performance, flexibility, and low power consumption, making it perfect for modern, battery-powered applications.

The necessity of such a middle-ground is why USB 2.0 has never lost relevance even as we await USB4 and other multi‑gigabit interfaces. USB 2.0’s 480 Mb/s high‑speed mode strikes a sweet balance of bandwidth, cable length, and power consumption. It remains ubiquitous in test equipment, biometric sensors, industrial peripherals, and consumer add‑ons. Unlike legacy USB 2.0 controllers with limited endpoints and insufficient processing power, EZ USB™ FX2G3 is designed to meet the demands of modern sensors and secure data transmission.

A dual‑core heart with headroom

One of the most striking features of FX2G3 compared with earlier USB controllers is its dual‑core architecture. Previous devices like FX2LP were built around an 8051 CPU, while the intermediate FX2G2 moved to an ARM9 core. EZ USB™ FX2G3 now pairs a 150 MHz Arm® Cortex®‑M4F with a 100 MHz Arm® Cortex®‑M0+. By dedicating one core to intensive tasks and the other to housekeeping, the controller can offload real‑time workloads from the host processor. In a thermal imaging accessory, for example, the M4 core performs contrast enhancement, region‑of‑interest cropping or color mapping, while the M0+ handles I2C sensor polling, UART debug output or power‑management routines. Competing controllers typically rely on a single core with far less headroom, which forces developers to move signal processing to the host or add external processors.

More endpoints, less juggling

USB endpoints act like communication channels between the device and host. Many USB 2.0 controllers limit you to just a few endpoints, which quickly run out when streaming video, audio, control messages, and telemetry simultaneously. FX2G3 overcomes that bottleneck by supporting up to 32 endpoints—16 IN and 16 OUT. Every endpoint can be configured as bulk, interrupt, or isochronous; for instance, a thermal camera can dedicate separate channels to high‑bandwidth sensor frames, low‑bandwidth status updates, and bidirectional control commands without time‑division multiplexing. For developers, this means simpler firmware and more predictable latency.

Memory and throughput to match the bus

Abundant on‑chip memory is essential for buffering frames and preventing underflows or overruns. Where many controllers include only a few kilobytes of RAM, FX2G3 offers 512 KB of flash, 128 KB of SRAM, 128 KB of ROM, and an impressive 1 MB of dedicated buffer SRAM. The controller’s high‑bandwidth DMA engine moves data between the buffer and the USB link at the full 480 Mb/s without burdening the CPU. For example, in a thermal camera solution, an RGB sensor at 1280×720 resolution, 16 bits per pixel, and 20 frames per second, plus a thermal sensor at 160×124×16 bits per pixel and 10 frames per second generates about 298 Mb/s which FX2G3’s buffer and DMA can handle comfortably. Such capacity eliminates the need for external SRAM or FPGAs to stage data.

Adaptable interfaces for modern sensors

Sensor diversity is growing. Cameras, image sensors, audio microphones, and inertial measurement units, all need to talk to the controller. Therefore, FX2G3 has a General Programmable Interface (GPIF III) which is a 16‑bit parallel bus with ten control signals running up to 100 MHz. This interface is programmable via state machines, enabling custom handshakes with various image sensors or FPGAs. In contrast, many controllers offer only serial interfaces or limited parallel ports, forcing designers to add glue logic or FPGAs for video streaming. On top of GPIF III, FX2G3 includes six Serial Communication Blocks (SCBs) that can be configured as I2C, SPI, UART, or CAN, plus a Quad‑SPI port that supports single, dual, quad, and octal modes. Two dedicated SPI channels provide direct connections for thermal imagers. There’s even a PDM‑to‑PCM converter for digital microphones, a full‑speed USB port for virtual COM functions and a Low‑Voltage CMOS (LVCMOS) interface for simple parallel sensor connection. This breadth of interfaces allows designers to connect sensors without external converters or interface chips.

Security by design, not as an add‑on

Embedded devices increasingly handle personal and proprietary data. Leaving security as an afterthought invites firmware tampering or data interception. EZ USB™ FX2G3 integrates a hardware cryptography engine that accelerates AES, RSA, and SHA algorithms and it also supports HMAC and CMAC message authentication codes while including a true random‑number generator. These features enable secure channel setup, encrypted data streams and authentication without taxing the CPU. A ROM‑based root of trust provides secure boot and ensures that only authenticated firmware runs; test and debug ports can be disabled in production. A one‑time‑programmable eFuse array stores encryption keys and device identifiers. Competing controllers often lack such dedicated hardware security features, requiring additional chips or host‑side cryptography.

Power efficiency and compact packaging

Portable accessories live by their battery. EZ USB™ FX2G3 operates over a wide 1.7 V–3.6 V range and features deep‑sleep modes with SRAM retention for quick wake‑up. Such modes allow a thermal camera or biometric sensor to sleep while idle yet resume streaming instantly when needed. The controller’s compact 8 mm × 8 mm land‑grid array packages (56‑pin and 104‑pin) suit space‑constrained boards. Integrating memory, interfaces and security into a single chip reduces board area and simplifies power‑supply design.

Well suited for a range of USB applications

Thermal imaging illustrates how these features come together. Thermal cameras detect infrared radiation and produce temperature‑mapped images, enabling everything from electrical fault detection and building inspections to contactless medical screening and night‑vision surveillance. A modern thermal accessory often combines a long‑wave infrared sensor with an RGB sensor to overlay thermal data on a visual scene for context. FX2G3’s GPIF III interface can connect directly to the focal‑plane array sensor, while its two SPI channels control the sensor’s configuration. The device’s large buffer SRAM stores continuous frames from both sensors, and the dual‑core CPU performs basic image processing—contrast enhancement, palette mapping, or region‑of‑interest extraction—before streaming data over USB.

In portable thermal cameras, power is everything. The controller’s low‑voltage operation and deep‑sleep capabilities extend battery life while still providing instant response. Onboard cryptography ensures that sensitive measurement data or firmware cannot be tampered with. With up to 32 endpoints, the camera can maintain separate channels for thermal frames, RGB frames, camera controls, and firmware updates, avoiding bottlenecks.

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Figure 2: Snapshot of a live Output from EZ-USB™ FX2G3's thermal module

Biometrics like fingerprint or facial recognition rely on fast, secure processing. FX2G3’s 1 MB buffer stores raw images while the M4 core extracts features while the hardware cryptographic engine protects templates and verifies authenticity before a host grants access. Because the controller manages sensors and encryption, the host sees a simple, secure USB device, reducing complexity.

In scanners and document imaging equipment, large high‑resolution frames must be transferred without losing lines. FX2G3’s numerous endpoints allow distinct channels for data, commands, and acknowledgements, and the DMA engine wraps and sends packets autonomously. This cuts down on firmware complexity and ensures that stepper‑motor control on the M0+ does not interrupt image streaming.

Medical equipment and test and measurement devices such as oscilloscopes, logic analyzers, and data‑acquisition systems benefit from predictable streaming. The combination of high‑bandwidth DMA and multiple endpoints allows continuous capture while the controller performs FFTs or compression on its M4 core. Its CAN capability suits automotive tools, and built‑in cryptography protects logs for regulatory compliance.

Edge computing and industrial automation increasingly push machine vision or data preprocessing to the device. FX2G3’s dual‑core CPU and assortment of interfaces let a designer attach multiple cameras, lidars, or inertial sensors via I2C, SPI, or CAN, fuse their data and stream results to a host or cloud. Its deep‑sleep modes extend battery life in IoT nodes, and its security features protect firmware updates and communication channels. Hybrid imaging and augmented‑reality systems also benefit by combining thermal and visible cameras, as they can identify heat anomalies and overlay them on 3D scenes or AR displays.

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Figure 3: Camera application using EZ-USB™ FX2G3

Final thoughts

USB 2.0 has remained relevant because it offers a combination of speed, simplicity, and low power that fits portable and embedded devices. However, many existing controllers have not kept pace with modern sensor demands or security requirements. Infineon’s EZ‑USB™ FX2G3 reimagines the USB 2.0 controller for contemporary applications by marrying a dual‑core processor with abundant memory, flexible interfaces, integrated cryptography and power‑efficient operation. The result is a compact device that can handle complex streaming tasks, real‑time processing and robust security without the cost or complexity of an application processor or FPGA. Whether you are developing a thermal camera, biometric scanner, portable test instrument or edge‑computing module, FX2G3 provides the bridge between “too simple” and “overkill”.

Access detailed technical documentation, reference designs, and development kits for the EZ‑USB™ FX2G3 on Infineon’s official product page.