FINANCE
Smart Multi-Card Digital Payment Solution.
HARDWARE | FIRMWARE | MOBILE/WEB APPS
Project Overview
Developed a next-generation smart card capable of storing and managing 8–10 digitized debit/credit cards, supporting major payment schemes like Visa, Mastercard, and Amex. The user can select a desired card via a mobile app and perform transactions via NFC or swipe, with secure OTA provisioning and lifecycle management of stored cards.
Client Requirement & Objectives
Multi-Card Storage & Support: The smart card must be capable of storing up to 10 physical debit/credit cards digitally, supporting various card types and global payment schemes.
Mobile App-Driven Provisioning: Users should link cards to the app, which fetches digitized versions from the bank servers and securely transmits them to the card.
Secure Card Management: The system should support adding and deleting cards, including automatic handling of expired cards and dynamic selection during payment.
Independent Operation: Once provisioned, the card should be operable independently of the mobile app, allowing both NFC-based and traditional swipe-based payments.
System Design & Build
Ultra-Slim Embedded Architecture: Engineered a compact PCB layout and embedded system design to match standard credit card dimensions, housing NFC, magstripe, display, and microcontroller units.
Secure Communication Protocols: Implemented end-to-end encryption between mobile app, backend server, and smart card using secure BLE, TLS protocols, and tokenized card data.
User Interface & Selection: Designed a minimal, on-card display and capacitive touch system allowing users to select the card in real-time before presenting it to a terminal.
Power Optimization & OTA: Incorporated low-power chipsets and dynamic sleep-wake cycles, while enabling secure over-the-air (OTA) updates with minimal energy consumption.
Project Tech Stack
Key Challenges & Solutions
Physical Size & Integration Constraints: Fitting all electronic components, battery, and antenna in the thin profile of a traditional card was addressed through multi-layer flexible PCB design and component miniaturization.
Power Efficiency: Achieved 1–2 months of battery life using ultra-low-power BLE modes, display timers, and energy-efficient NFC activation only during transactions.
Secure Provisioning Pipeline: Built a secure backend and mobile app architecture with certificate pinning, tokenized communication, and secure element storage on the card for safe card download and deletion.
Reliable OTA Updates in Low Power Mode: Developed a lightweight OTA protocol capable of updating firmware and configurations within strict battery constraints, without degrading user experience or security..
Client
XardPay creates smart digital cards that securely store and let users switch between multiple debit and credit cards with ease.
How can we Help You?
Get in touch and let's find out how we can curate our offerings to match your organization's needs.