GROW-R307S Fingerprint Module

Description : The GROW-R307S is an optical fingerprint sensor module commonly used in access control systems, biometric locks, attendance systems, and embedded electronics projects such as Arduino, ESP32, and Raspberry Pi. It integrates fingerprint image capture, feature extraction, and fingerprint matching inside a single all-in-one module. ???? Technical Specifications Sensor Type: Optical Resolution: 500 DPI Capture window: approx. 14 × 18 mm Power Supply voltage: 4.2 V to 6 V DC (typically 5 V) Typical operating current: ≤ 75 mA Communication UART (TTL level) Default baud rate: 57,600 bps Adjustable baud rate: 9,600 – 115,200 bps USB version available on some models Storage Capacity: Up to 1000 fingerprints Data sizes: Feature file: 256 bytes Template (model): 512 bytes Performance Image acquisition time: < 0.3 s Matching time: < 0.2 s Matching modes: 1:1 (verify against a known ID) 1:N (search entire database) Error rates: FRR (False Reject): ≤ 0.1 % FAR (False Accept): ≤ 0.0001 % Durability Lifetime: Up to 100 million touches Static protection: Up to 15 kV Environment Operating temperature: –20 °C to +50 °C Dimensions: approx. 52 × 20 × 22 mm ???? Pinout (6-pin UART version) Pin Name Description 1 VCC Power supply 5V 2 GND Ground 3 TXD Data output (to microcontroller RX) 4 RXD Data input (from microcontroller TX) 5 TCH Touch detection signal 6 3.3V Optional low-power output ????️ How It Works 1) Fingerprint Enrollment User places finger twice. The module: Captures images Extracts fingerprint features Generates a template Stores it in internal flash memory 2) Fingerprint Recognition When a finger is placed: The sensor captures and processes the image Matches it against: A specific ID (1:1), or All stored fingerprints (1:N) Returns: Match success Match failure ID number (if matched) ???? Common Applications Biometric door locks Access control systems Time attendance systems Secure boxes and safes Arduino / ESP32 / Raspberry Pi projects Smart home and IoT systems ✔️ Tips for Use Always use a stable 5V power supply. Connect UART properly: TX → RX, RX → TX. Keep the sensor surface clean. If no response: check baud rate settings. Protect the module from voltage spikes.