Renesas has released a microprocessor integrating multimedia functions and AI acceleration. Available now, the new RZ/G3E is an Arm-based chip targeting human-machine interfaces (HMI) in industrial applications.
Key Features
- Computing—the Renesas RZ/G3E features a four-core Arm Cortex-A55 cluster.
- Control—an Arm Cortex-M33 subsystem, including peripherals, handles control and system-management functions.
- AI—the chip has an Ethos-U55 accelerator (NPU) in a 256-MAC configuration, Arm’s largest for this NPU. The RZ/G3E block diagram doesn’t show it directly connected to the M33, indicating another M33 could be hosting the NPU.
- Graphics—a low-cost Arm Mali-G52 is available for GUI effects.
- Multimedia—engines for image scaling, color-space conversion, and other basic image processing, plus a video encoder/decoder (codec) and camera and display interfaces, provide HMI functions and support up to 4K resolution.
- High-speed I/O—three USB interfaces, a pair of Gigabit Ethernet ports, and two lanes of PCIe Gen 3 provide connectivity.
Feature Analysis
CPU
An eight-year-old 64-bit “little” core, the Arm Cortex-A55 is power and area efficient. Like its similar predecessor, the Cortex-A53, the A55 still wins slots in new processor designs. Arm’s subsequent cores, such as the Cortex-A520, weren’t nearly as efficient and didn’t see comparable adoption except in smartphone chips. The Cortex-A320 addresses the issue but is much more expensive to license than recycling the A53 and A55, we believe.
NPU
The Ethos-U55 dates back to 2020 and improves upon the earlier Ethos-N37. However, a newer Arm Ethos-U85 could be similarly configured and work with the A55 cluster, a more natural pairing given that the software requiring AI offload will run on those CPUs, not the M33. A better design, the U85 would deliver greater performance and support transformer models. As with the CPU selection, licensing terms could’ve governed Renesas’s choice of the U55.
On-Chip Bus
The Renesas RZ/G3E comprises multiple subsystems, each with an on-chip bus that isolates local traffic. TrustZone Controllers (TZCs) provide address-space isolation of memories and some peripherals; their presence indicates the chip has no system MMUs or memory coherency. It’s the result of microcontroller engineers developing a microprocessor. It forces software developers to do extra low-level work and saps the performance of high-speed peripherals such as video codecs, Ethernet ports, and PCIe-connected devices.
Competition
Products competing with the Renesas RZ/G3E include the NXP i.MX 95 and the Rockchip RK3568J.
NXP i.MX 95
Sampling now, the NXP i.MX 95 promises a few advantages. It also employs the Cortex-A55 but in a six-core cluster. A Cortex-M33 handles management functions, and NXP adds a more powerful Cortex-M7 for real-time processing. The i.MX 95 adds a 10 Gigabit Ethernet port and a proper image signal processor (ISP). Although NXP was Arm’s lead Ethos-U55 customer, the company switched to a proprietary NPU offering four times the raw performance and probably even greater real-world throughput.
Like the RZ/G3E, the i.MX 95 is qualified for extended temperatures (–40°C to 125°C) and will be available for 15 years. Unlike the Renesas chip, the i.MX 95 supports industrial (SIL2) and automotive (ASIL B) safety certifications and provides a secure enclave. Safety certification is essential for some industrial customers and is, therefore, an important i.MX 95 advantage. A more capable processor, the i.MX 95 should command a higher price than the RZ/G3E.
Rockchip RK3568J
Sold since 2022, the Rockchip RK3568J is similar to the RZ/G3E, sporting a four-core Cortex-A55 cluster but no Cortex-M CPU, as Table 1 shows. Raw NPU performance is 1 TOPS, twice that of the Renesas chip. Minor differences include supporting only up to 1080p (FHD) for video encoding and providing an ISP. Rockchip rates the RK3568J for extended temperatures but withholds the exact range. The company doesn’t disclose safety certifications or long-term availability commitments. We, therefore, expect conservative industrial OEMs to prefer the RZ/G3E. The RK3568 sells for less than $15 compared with $47 for the Renesas processor—about the price of an entire RK3568 single-board computer (quantity 500).
Feature Comparison Table
Renesas |
NXP |
Rockchip |
|
|---|---|---|---|
Application CPU |
4× Arm Cortex-A55 @ 1.8 GHz |
6× Arm Cortex-A55 @ 2.0 GHz |
4× Arm Cortex-A55 @ 2.0 GHz |
Control CPU |
Cortex-M33 |
Cortex-M33, |
None |
NPU |
Arm Ethos-U55, 0.5 TOPS |
Proprietary, |
Proprietary, |
GPU |
Arm Mali-G52 |
Arm Mali-G310 |
Arm Mali-G52 |
Video Codec |
4K encode/decode |
4K encode/decode |
4K decode, FHD encode |
Memory Interface |
LPDDR4X |
LPDDR5 |
LPDDR4X, DDR4 |
Ethernet Interface |
2× GbE |
2× GbE, |
2× GbE |
PCIe Interface |
2 lanes Gen 3 |
2 lanes Gen 3 |
2 lanes Gen 3 |
Production |
2Q25 |
2Q25 |
2022 |
Bottom Line
The Renesas RZ/G3E is a competitive microprocessor with multimedia and graphics functions, enhanced by an integrated AI accelerator. An NPU is important and is becoming standard in products like this. Because image classification will be a primary NPU application, the newest technology and greatest performance aren’t needed. Nonetheless, the RZ/G3E’s Arm Ethos-U55 is wimpier than the competition and doesn’t support transformer models, which are becoming used for image processing.
Renesas, like NXP, is squeezed between companies like Rockchip and those like MediaTek and Qualcomm. Rockchip and similar Asian suppliers offer comparably featured processors at much lower prices. On the other side, smartphone-chip companies are adapting their products to industrial and automotive applications, offering higher performance and amortizing R&D over the smartphone market. Extended temps and 15-year availability are differentiators, as is safety certification. Competitive as the RZ/G3E is, it’s becoming a niche product.