Fingerprint Scanner - TTL (GT-521F52)

Adding biometric security to your hardware is often a complex and frustrating process. The GT-521F52 Fingerprint Module from ADH-Tech eliminates that friction by handling all the intense mathematical lifting internally! Powered by a 32-bit ARM Cortex M3 processor and a high-accuracy optical sensor, this module scans, analyzes, and stores fingerprint templates entirely onboard, passing simple verification commands to your microcontroller over TTL Serial.

To register a user, simply send the enrollment command and press the finger against the sensor three times. From there, the scanner takes over, requiring less than 1.5 seconds to accurately identify a unique print. More details on setting up your own fingerprint sensor can be found in our Hookup Guide.

Precision and Capacity

This upgraded module is designed for large-scale databases and highly varied environmental conditions. It provides a great "mid-range" option for those of you looking to add a little bit of biometric security to your project.

• Massive Storage: The GT-521F52 stores up to 3,000 unique fingerprint templates, making it ideal for large offices or shared-access systems.
• Forgiving Detection: The ultra-thin optical sensor features 450 dpi resolution and 360-degree recognition for scanning fingers that aren't perfectly aligned. It also accurately reads dry, moist, or rough fingerprints!
• High Security: Achieves a false acceptance rate of less than 0.001% and a false rejection rate of less than 0.1%.
• Smart Power: Features a "Wake up on Finger" function to conserve energy when not in active use.

Database Management

You'll have direct access to this scanner's internal database because it communicates over a standard UART protocol. Fingerprint templates can be downloaded directly from the unit and uploaded to other modules, allowing you to deploy multiple scanners across a building without forcing users to register at every door. You can even retrieve the analyzed template data or pull raw images straight from the optical sensor for highly custom applications.

While the board features two onboard JST-SH connectors identical to those used in our Qwiic ecosystem, this module is NOT Qwiic- or I²C-compatible. It relies entirely on a standard serial connection (Vcc, GND, Tx, and Rx). That said, all of our Qwiic cables, including our breadboard jumper, will work with this board.

By offloading the complex image processing to a dedicated onboard processor, this module turns advanced biometrics into a straightforward serial component for any custom security layout.