Rtl9210b Datasheet 2021 May 2026

Realtek RTL9210B-CG is a dual-protocol USB bridge that acts as a "host" for both PCIe/NVMe and SATA drives, allowing for automatic switching between the two. Key Technical Specifications Host Interface : USB 3.1 Gen 2 (up to 10Gbps). Device Interfaces : PCIe Gen3 x2 (up to 16Gbps bandwidth). : SATA Gen3 (up to 6Gbps). Auto-Switching

: Uses the PEDET interface to detect and switch between PCIe and SATA modes automatically. Power Management

: Supports link power management (PCIe L1.Off and L1.Snooze) and dynamic switching power states for efficiency. : 68-pin QFN Green package. Reference Design & Schematics

For hardware development, detailed 2020-2021 period documentation includes: Official Datasheet RTL9210B-CG Datasheet Rev 1.1

(released June 19, 2020) provides pinout and electrical characteristics. Demo Board Schematic RTL9210 68-Pin Demo Board Schematic outlines essential connections for power, M.2, and USB. Firmware & Tools

As of early 2021, firmware updates improved compatibility for varied SSD models. Update Tools : Most updates use the UTHSB_MPtool on Windows. Unbricking rtl9210b datasheet 2021

: If the controller becomes unresponsive, it can be forced into internal ROM mode by shorting Pins 1 (CS#) and 8 (VCC) of the SPI flash memory chip during connection. Community Resources bensuperpc/rtl9210 GitHub repository

5. Firmware Ecosystem (as of 2021)

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

• UASP (USB Attached SCSI Protocol) – mandatory for >400 MB/s performance
• TRIM passthrough
• S.M.A.R.T. attribute reading (via vendor-specific SCSI commands)
• Configurable spin-down timer (from 5 min to never)
• Idle power state (PCIe ASPM L1.1 / L1.2)
• LED patterns (solid = active, blink = R/W, off = standby)

Later 2021 revisions (firmware 1.27+) added:

• Support for PCIe Gen 3 x2 link speed locking (fixes compatibility with some drives)
• Improved Samsung PM9A1 and WD SN850 compatibility
• Optional “no standby” mode for real-time applications

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.

Where to get official details

• The full datasheet (including electrical characteristics, package drawings, register maps, and timing diagrams) is provided by Realtek or authorized distributors; obtain the official 2021 datasheet from Realtek support or your module/enclosure vendor.

4. Power Management and Thermal Performance (2021 data)

One major reason for the RTL9210B’s popularity in 2021 was its low power consumption. Realtek claimed: Realtek RTL9210B-CG is a dual-protocol USB bridge that

• Active (read/write): ~1.5W – 2.0W (depending on drive)
• Idle (no access): <0.5W
• Suspend/Standby: <0.1W

Thermal characteristics (from datasheet):

• Junction-to-ambient (θJA) : 28°C/W (with 2-layer PCB)
• Maximum junction temperature: 125°C

In practice, 2021 enclosures using the RTL9210B ran significantly cooler than ASM2362 designs, making them suitable for high-performance NVMe drives without active cooling.

2. Absolute Maximum Ratings & Operating Conditions (2021 Specs)

This section is critical for power supply design. According to the 2021 document:

| Parameter | Symbol | Min | Max | Unit | | :--- | :--- | :--- | :--- | :--- | | Core Supply Voltage | VDD_CORE | -0.3 | 1.26 | V | | I/O Supply Voltage | VDD_IO | -0.3 | 3.63 | V | | PCIe Reference Clock | REFCLK | - | 100 | MHz | | Storage Temperature Range | T_STG | -55 | +150 | °C | | Operating Junction Temp | T_J | 0 | +85 | °C |

2021 Update: The datasheet explicitly warns that absolute maximum ratings for the 1.05V internal regulator should not be exceeded for more than 10 ms during power-on sequencing. Failure to follow this leads to latch-up in the PCIe PHY. UASP (USB Attached SCSI Protocol) – mandatory for

1. Key Specifications

• Interface (Host): USB 3.2 Gen 2 (backwards compatible with USB 3.0/2.0).
  • Speed: Up to 10 Gbps.
  • Connector: Typically USB Type-C.
• Interface (Device): PCI Express Gen 3 x2 (NVMe).
  • Speed: Up to 8 Gbps (PCIe 3.0 x2 lane).
• Storage Support:
  • Form Factor: M.2 2280 / 2230 / 2242.
  • Key: M-Key (NVMe). Note: It does not support SATA M.2 drives (B-Key).
• Flash Memory: Embedded SPI Flash interface for firmware updates.

6. Firmware & Register Map Highlights (from 2021 Datasheet)

The 2021 version introduced new configuration registers accessible via USB Vendor Commands (VSC). Key addresses:

• 0x30 (Power Management): Bit 4 now enables "Smart Sleep" (5-second delay instead of 1-second).
• 0x78 (LED Control): Changed from 0x00 (always on) to 0x03 (blink on activity) as default.
• 0xD0 (Sector Size Emulation): Allows spoofing 512e for 4Kn drives – required for Windows 7 compatibility.

Checksum verification: The 2021 datasheet warns that modifying register 0xFC without recomputing CRC16 over the SPI flash will brick the bridge until external programmer re-flash.

7. Design Considerations for Engineers (2021 Guidelines)

The 2021 datasheet includes a 24-page PCB layout guide. Critical points:

1. USB 3.1 Gen 2 traces: differential impedance 90 Ω ±10%, length mismatch < 0.5 mm, no vias in high-speed pairs if possible.
2. PCIe Gen 3: 85 Ω differential (or 100 Ω depending on drive). Keep length mismatch < 2 mm between lanes.
3. SPI flash placement: As close as possible to the RTL9210B (< 30 mm trace length).
4. Decoupling capacitors: 0.1 µF + 10 µF per power pin; bulk 100 µF on 3.3V input.
5. Thermal vias under the exposed pad – at least 9 vias (0.3 mm diameter) to bottom-layer copper pour.

Realtek also provided a reference design (RTL9210B-CG EVB) which included a USB-C receptacle, NVMe M.2 M-key slot, SPI flash socket, and two LEDs.