Nationz Showcases Dual Optical Module MCUs at CIOE, Targeting CMIS 5.3 and EU CRA Compliance
At CIOE, Nationz showcased two optical module MCUs — the N32H493 and the newly added N32DP474 — with pin-to-pin compatibility with mainstream overseas solutions for PCB reuse and 1.8V direct DSP connection, targeting CMIS 5.3's mandatory CDB authentication and EU CRA compliance.
The 27th CIOE China International Optoelectronic Exposition ran in Shenzhen from 9 to 11 September 2026. At its booth, Nationz (Nation Technologies) presented two optical module MCUs: the N32H493 for the 800G/1.6T segment and the newly added N32DP474 for 400G/800G. In parallel, the company gave a talk at the 24th IFOC optical communications conference on high-performance security solutions for 800G/1.6T optical modules — its MCUs enabling CMIS compliance and EU CRA readiness for export markets. PCBA boards from several optical module customers were displayed across the co-located CIOE, IICIE and elexcon shows. On 10 September the N32H493 received the 2026 Hardcore MCU Chip Award at a ceremony hosted by Xinshiye, selected, according to the organiser, from more than 1,100 competing products.
What each MCU targets
The N32H493 addresses 800G/1.6T high-speed optical modules. It is based on an ARM Cortex-M4F core at 240 MHz with an FPU, DSP instructions and an 8KB I-Cache, and integrates 1MB of Flash (dual-bank, with seamless OTA upgrade) plus 516KB of SRAM. On the analogue side it includes a 2.5V Vrefbuf internal reference voltage buffer, two 12-bit DACs and three 12-bit 4.7Msps high-speed ADCs. Communication interfaces cover I2C, SPI and U(S)ART, with 1.8V VDDIO for direct connection to a DSP without level shifters.
The N32DP474 addresses 400G/800G modules, also with an ARM Cortex-M4F core at 240 MHz plus FPU and MPU, 512KB of dual-bank Flash and 196KB of SRAM, four 12-bit DACs, a 2.5V Vrefbuf and four 4.7Msps 12-bit ADCs. It comes in an FCBGA81 package optimised for the narrow card layouts used in 400G/800G designs.
Pin compatibility is the most tangible selling point
The N32H493 is offered in BGA64, BGA72, BGA80, BGA81 and BGA90 packages that are pin-compatible with mainstream WLCSP72/80/81/90 and UFBGA64 solutions; the N32DP474's FCBGA81 is pin-compatible with mainstream WLCSP81 parts. For module makers this means existing PCB layouts can be reused, cutting board rework and development time. Given that an optical module MCU accounts for less than 1% of the cost of a high-end module — which historically gave module vendors little incentive to switch suppliers — the ability to swap without a board redesign is often the precondition for a replacement project even getting started.
CMIS 5.3: authentication moves from optional to mandatory
OIF's CMIS 5.3 implementation agreement adds a group of security-related commands to the Command Data Block set, including secure device authentication commands in the 0400h–0406h range, plus 0044h "Security Features and Capabilities" and 0050h "Get Application Attributes". As Liu Yaming, Marketing Director at Nationz, puts it: the new CDB command group in CMIS 5.3 covers secure device authentication, certificate queries and firmware signature verification, shifting optical module MCUs from optional certification towards mandatory identity authentication. For module vendors this means the controller must support certificate reads, signature digests and device identity verification at the protocol stack level, rather than merely running digital diagnostic monitoring.
The EU CRA timeline and what it means in practice
The EU Cyber Resilience Act (Regulation (EU) 2024/2847) entered into force on 10 December 2024. According to the timeline published by the European Commission's digital strategy pages, vulnerability and incident reporting obligations apply from 11 September 2026, while the main obligations — essential cybersecurity requirements, conformity assessment, CE marking and technical documentation — apply in full from 11 December 2027.
Applied to optical modules, the CRA covers the full chain of identity authentication, secure boot, key storage, vulnerability handling and OTA firmware updates. Nationz states that both MCUs include a true random number generator and support ECC P-384, ECDSA SHA-384 and X.509 v3 certificate chains for key generation, encrypted storage and digital signatures, and that they support both China's SM2 and international ECC/RSA algorithms. The company says the parts meet the CRA's Important Class I grouping requirements and that it will supply component compliance documentation to support customers' end-product conformity work. This is the vendor's own position; module makers pursuing end-product certification should base decisions on the compliance documents actually obtained.
Validation data and industrial-grade specifications
Reliability claims ultimately come down to numbers. The vendor-published specifications are as follows:
- Operating temperature: -40°C to 105°C, with some variants rated to 125°C.
- Immunity: power-rail EFT ±4kV, live ESD ±10kV.
- Interface validation: 103 dedicated I2C validation items covering timing compatibility, read/write anomalies, high and low temperature, and hot plugging.
- Firmware upgrade: dual-bank hardware architecture supporting secure OTA without interrupting traffic.
According to the vendor and information disclosed at the show, the full set of 103 validation items has been completed at leading optical module customers, covering complex conditions such as timing compatibility, read/write anomalies, high and low temperature and hot plugging. For context, Nationz puts the 2026 global market for high-end optical module host controllers at USD 1.0–1.5 billion with a domestic (Chinese) supply share below 5%, and brokerage commentary indicates the N32H493 is already in small-volume supply.
HSY Perspective
As an authorised distributor for Nationz, HSY advises optical module customers to handle three things up front. First, turn "swap without a board change" into a verifiable checklist: identical footprints do not guarantee identical I2C timing, power-up sequencing, reset behaviour or hot-plug response. Ask the vendor directly for the test items and results behind the 103 validation points and map them onto your own board and DSP combination rather than adopting the conclusion wholesale. Second, for export-oriented customers, work the compliance schedule backwards from the deadlines: CRA reporting obligations already apply from 11 September 2026 and the main obligations from 11 December 2027, and end-product certification depends on component-level documentation from the MCU side — technical documentation, vulnerability handling process, support-period commitments. Request those materials during selection, not before sending the finished product for testing. Third, choose by speed grade and card space: N32H493 for 800G/1.6T designs, and the FCBGA81 N32DP474 for 400G/800G designs with tight board area; if a WLCSP81 layout already exists, a pin-to-pin evaluation can begin immediately. At the protocol level, the 0400h-series authentication commands in CMIS 5.3 require the MCU to provide certificate chains and signature verification, so build those capabilities into the firmware architecture early to avoid rework later.
Sources: Nationz newsroom "N32H493 wins 2026 Hardcore MCU Award — CIOE/IICIE/elexcon highlights" (https://www.nationstech.com/about/news/product/7865.html, 10 September 2026); C114 "In the name of security: Nationz shows two MCU solutions targeting AI high-speed optical modules" (https://m.c114.com.cn/w5472-1317339.html, 11 September 2026); OIF "CMIS 5.3 Implementation Agreement" (https://www.oiforum.com/wp-content/uploads/OIF-CMIS-05.3.pdf); European Commission, Cyber Resilience Act (https://digital-strategy.ec.europa.eu/en/policies/cyber-resilience-act)