Secure 3 Click carries the ATSHA204A, a cryptographic coprocessor with secure hardware-based key storage from Microchip. The Click is designed to run on either 3.3V or 5V power supply. Secure 3 Click communicates with the target microcontroller over an I2C interface. It is ideal to use for: * Secure download and boot - authentication and protect code in-transit * Ecosystem control - ensure only OEM/licensed nodes and accessories work * Anti-cloning - prevent building with identical BOM or stolen code * Message security - authentication, message integrity, and confidentiality of network nodes (IoT) NOTE: The Click comes with stacking headers which allow you to combine it with other Clicks more easily by using just one mikroBUS™ socket. ATSHA204A FEATURES The ATSHA204A is a member of the Microchip CryptoAuthentication™ family of high-security hardware authentication devices, which uses Secure Hash Algorithm (SHA-256) with 256-bit key length, message authentication code (MAC) and hash-based message authentication code (HMAC) options. It has a flexible command set that allows use in many applications. The ATSHA204A device includes an Electrically Erasable Programmable Read-Only Memory (EEPROM) array that can be used for key storage, miscellaneous read/write data, read-only, secret data, consumption logging, and security configuration. Access to the various sections of memory can be restricted in a variety of ways, and the configuration can then be locked to prevent changes.