BANKING. INSURANCE

Biometric OTP Generator with Secure Authentication

Project Overview

A compact OTP-generating device with built-in biometric authentication to ensure secure, real-time identity verification. Designed for portability and tamper resistance, the device supports BLE connectivity and was successfully produced in a 10,000-unit initial manufacturing run.

HARDWARE | FIRMWARE | MOBILE/WEB APPS | EMS MANUFACTURING

Client Requirement & Objectives

Biometric Authentication

The device needed to register and authenticate fingerprints using an onboard fingerprint sensor before generating an OTP.

Real-Time OTP Display

A built-in OLED screen was required to display the generated OTP securely to the user upon successful fingerprint match.

Portable & Tamper-Proof Form Factor

The hardware needed to be small enough for keychain attachment, durable, and resistant to tampering.

BLE Connectivity

A BLE module was to be integrated for initial fingerprint registration and for syncing device data with the mobile app and backend server.

System Design & Build

Low-Power Architecture

Built a power-optimized embedded system with real-time clock (RTC), fingerprint module, and OLED, designed for long-term use without recharging.

Secure OTP Algorithm

Implemented a time-based OTP generator that ensures server-side OTP validation with device clock synchronization and unique identifiers.

Smart Power Switching

Integrated a physical power switch to wake up the microcontroller only during fingerprint activity, conserving energy while keeping the RTC active.

Scalable Manufacturing

Completed end-to-end production of 10,000 units, including calibration and QA to ensure OTP accuracy and clock drift minimization. .

Key Challenges & Solutions

Power Management

Balancing power-hungry components like the fingerprint sensor and OLED was critical. We optimized firmware to alternate their activity and extend battery life across months of usage.

Efficient Wake-Up Control

A custom power switch was implemented to wake the microcontroller only when the fingerprint sensor is touched, reducing idle consumption while maintaining RTC operation.

Secure BLE Pairing

Ensured encrypted communication during fingerprint registration and OTP syncing by implementing secure BLE handshakes and linking with server validation protocols.