Rtl9210b Datasheet 2021 May 2026

The RTL9210B is firmware-dependent. The 2021 datasheet references firmware version 1.23.x as the initial production release, with key capabilities:

Later 2021 revisions (firmware 1.27+) added:

Flashing procedure (from application note AN-2021-09):
Via USB firmware update mode (hold RESET# and GPIO12 low during power-on) or using the Realtek Flash Tool over UART.

The RTL9210B is famous in the enthusiast community for its superior power management compared to competitors like the JMicron JMS583.

The 2021 datasheet provides updated power figures measured at 25°C ambient, with a Samsung PM981a 1TB NVMe SSD:

| State | USB Link | Current (5V) | Power | Temp Rise | | :--- | :--- | :--- | :--- | :--- | | Sleep (ASPM L1.2) | Suspend | 58 mA | 0.29 W | +2°C | | Idle (no trim) | Gen 2 (10G) | 320 mA | 1.6 W | +12°C | | Sequential Write (4KB) | Gen 2 (10G) | 890 mA | 4.45 W | +38°C | | Thermal Throttle (85°C) | Gen 1 (5G) | 610 mA | 3.05 W | N/A |

Critical 2021 Note: The RTL9210B will begin thermal throttling at 85°C junction temperature, reducing PCIe width from x2 to x1. Without a copper pad under the QFN, the chip will hit 105°C and shut down within 90 seconds of continuous writing.

Published: Mid-2021 Review | Part Number: RTL9210B-VC / RTL9210B-CG
Vendor: Realtek Semiconductor Corp.

  • Interface (Device): PCI Express Gen 3 x2 (NVMe).
  • Storage Support:
  • Flash Memory: Embedded SPI Flash interface for firmware updates.

    • The chip supports programmable LED output (Pin 35 in many configurations). rtl9210b datasheet 2021

    The RTL9210B datasheet from 2021 remains a vital document for anyone designing or repairing NVMe-to-USB adapters. It captures a mature phase of the chip’s development—after the early bugs were documented but before the shift to USB4 in late 2022.

    For engineers, the key takeaways are the updated power sequencing rules, the errata workarounds, and the PCB impedance requirements. For hobbyists, the 2021 sheet confirms that firmware tools like RTL9210B_FW_Tool_v1.19 are the last stable releases before newer versions introduced read-only bugs.

    Always cross-reference with the 2022 addendum if you need USB 3.2 Gen 2x2 support (20 Gbps)—the 2021 RTL9210B does not support that mode.

    Further Reading:

    Disclaimer: Specifications are based on the 2021 published data. Always consult the latest official datasheet from Realtek before finalizing a product design.

    The RTL9210B is distinct for its "dual-protocol" support, allowing it to interface with both NVMe (PCIe) NGFF (SATA)

    M.2 SSDs. This flexibility makes it a standard choice for "all-in-one" external drive cases. Key Technical Specifications Upstream Interface (USB): USB 3.2 Gen 2 with speeds up to

    Backward compatible with USB 3.2 Gen 1, USB 2.0, and USB 1.1. The RTL9210B is firmware-dependent

    Includes a built-in Type-C connector controller with power role swap and cable orientation detection. Downstream Interface (Storage): NVMe Mode:

    PCIe Gen3 x2 interface, supporting NVM Express (NVMe) 1.3 protocol. SATA Mode:

    Supports SATA Gen3 (up to 6Gbps) and is backward compatible with Gen2/Gen1. Storage Capacity: Generally supports up to max capacity for attached SSDs. Advanced Features Protocol Management: (USB Attached SCSI Protocol) and commands for optimized data transfer and drive longevity. Power Management:

    Dynamically switches power states for NVMe/SATA/USB to save energy and balance performance. Internal Controller:

    Embedded with customized RAM/ROM and SPI Flash to handle AHCI and NVMe drivers. Integration:

    Integrated 5V to 1V switching regulator and support for GPIOs, eFUSE, and UART interfaces. Resources & Documentation RTL9210B-CG - Realtek

    The Realtek RTL9210B Go to product viewer dialog for this item.

    is a high-performance USB bridge controller designed to connect both NVMe and SATA M.2 SSDs to a USB host. Unlike its predecessor, the RTL9210 (which only supports NVMe), the "B" variant is a dual-protocol solution that automatically detects and switches modes based on the drive inserted. Key Specifications Later 2021 revisions (firmware 1

    According to the 2020-2021 technical documentation from Realtek and reference Datasheets, the controller features:

    USB Interface: USB 3.1 Gen 2 (now often called USB 3.2 Gen 2x1) providing up to 10Gbps bandwidth.

    PCIe Interface: Supports PCIe Gen3 x2, delivering up to 16Gbps internal bandwidth for NVMe drives. SATA Interface: Supports SATA Gen3 for speeds up to 6Gbps.

    Protocols: Full support for UASP (USB Attached SCSI Protocol) for faster transfers and TRIM commands to maintain SSD longevity. Package: 68-pin QFN Green package. Why the 2021 Revision Matters

    The 2021 timeframe saw significant firmware and documentation updates focused on device stability:

    SSD Compatibility: Firmware released in late 2021 (v1.27.5) addressed connectivity and stability issues specifically for popular drives like the Samsung 980 Pro and Western Digital SN550.

    Power Management: Improved link power management (PCIe L1.Off and L1.Snooze) to reduce heat—a common issue in small M.2 enclosures.

    LED Logic: Updated behaviors for "Safe Eject" indicators on Windows and Mac systems. vs. RTL9210B Difference between these nvme enclosures : r/UsbCHardware