RTS5170
USB 2.0 SD and microSD card reader controller for PC and embedded applications
Product Overview
Description
The Realtek RTS5170 is a USB 2.0 SD and microSD card reader controller supporting SD, SDHC, and SDXC formats for PC and embedded applications requiring reliable memory card access.
This controller supports SD cards up to 2TB (SDXC) and provides transfer speeds up to 480 Mbps via USB 2.0 interface. The integrated 5V to 3.3V regulator simplifies power supply design.
RTS5170 is widely used in USB card readers, PC front panels, and embedded systems where SD/microSD card support is required. The compact package and minimal external components make it cost-effective for high-volume applications.
Product Series
RTS
Primary Application
USB card readers
Key Features
- USB 2.0 interface
- SD/SDHC/SDXC support
- microSD support
- Up to 2TB capacity
- Integrated 5V to 3.3V regulator
- Hot plug detection
- Write protect support
- Compact QFN package
Specifications
| Interface | USB 2.0 |
|---|---|
| Supported Cards | SD/SDHC/SDXC/microSD |
| Max Capacity | 2TB (SDXC) |
| Max Speed | 480 Mbps (USB 2.0) |
| SD Bus | Up to 50 MHz |
| Power | 5V input, integrated regulator |
| Features | Hot plug, Write protect |
| Operating Temperature | 0°C to +70°C |
| Package | QFN-24 |
| Drivers | Built-in Windows/Linux |
Applications
USB card readers
Electronic system design
PC front panels
Electronic system design
Embedded systems
Electronic system design
Industrial PCs
Industrial automation and control
Kiosk systems
Electronic system design
FAE Expert Insights
"RTS5170 is a solid, reliable SD card reader solution. The integration is good - built-in regulator reduces BOM cost. uSB 2.0 speed is sufficient for most SD card applications. We've used this in many designs without issues. it's the standard choice for basic SD card reading needs."
Reliable and cost-effective SD card reader solution
— Kevin Zhang, BeiLuo
Frequently Asked Questions
What is the maximum SD card capacity supported by RTS5170?
RTS5170 supports SDXC cards up to 2TB capacity. It also supports older SD (up to 2GB) and SDHC (up to 32GB) formats. The controller handles the different card types automatically. As larger SD cards become available, the 2TB limit may be increased through firmware updates depending on the specific implementation.
Supports up to 2TB SDXC. Sufficient for current SD card capacities.
Does RTS5170 require external drivers?
RTS5170 uses standard USB Mass Storage class drivers built into Windows, Linux, and macOS. No additional drivers are required for basic operation. The card reader appears as a standard removable drive when a card is inserted. Some implementations may include custom software for additional features, but the core functionality is driverless.
Plug-and-play with built-in OS drivers. No additional drivers needed.
What is the actual transfer speed with USB 2.0?
With USB 2.0 interface, RTS5170 can achieve sustained transfer speeds of 30-40 MB/s with fast SD cards. The USB 2.0 theoretical maximum is 60 MB/s (480 Mbps), but practical speeds are lower due to protocol overhead. For most SD card applications, this speed is sufficient. For UHS-I or UHS-II high-speed cards, consider USB 3.0 controllers.
30-40 MB/s typical. sufficient for standard SD cards. uSB 3.0 for high-speed cards.
Does RTS5170 support SD card write protection?
Yes, RTS5170 supports SD card write protection through both physical write protect switch detection and software-controlled write protection. When a card's physical write protect switch is enabled, the controller reports this status to the host. Software can also enable write protection for security purposes.
Full write protection support. Physical switch and software control.
Can RTS5170 read both SD and microSD cards simultaneously?
RTS5170 supports both SD and microSD card slots, but typically only one card can be active at a time in standard implementations. The controller switches between slots based on which card is inserted. For simultaneous dual-card access, two controllers or a specialized dual-slot solution would be required.
One card active at a time. Dual-slot for convenience, not simultaneous access.