Dual Secure Elements in Trezor Safe 7

Trezor Safe 7 builds on Trezor’s long-standing commitment to open, verifiable security by combining two independent secure elements—the open and auditable TROPIC01 and the certified OPTIGA Trust M.

Together, these chips form a that protects your wallet against tampering, brute-force PIN attacks, and counterfeit hardware.

Each secure element contributes a distinct layer of protection. TROPIC01 adds transparency through open verification, while OPTIGA Trust M provides certified security controls. The result is a wallet architecture that’s both transparent and resilient—a hallmark of Trezor’s open approach to hardware security.

Overview

The secure elements share three key responsibilities:

• Hardware-enforced PIN protection
• Device authenticity verification
• Secure randomness for wallet creation

Together, they form the foundation of Safe 7’s defense-in-depth architecture, where multiple independent hardware checks protect your wallet from both physical and digital attacks.

Hardware-enforced PIN protection

Your PIN is the key to your wallet, but it is never stored on the device. Instead, it is used to temporarily build the key that decrypts your private keys.

This process is secured by a collaboration between the main microcontroller (MCU) and the two secure elements.

Here is a simplified view of how they work together:

1. You enter your PIN: The MCU prepares your PIN for verification.
2. First check with TROPIC01: The MCU sends the prepared value to the TROPIC01 chip. Using its unique  mechanism, it mixes in its own secret and returns a transformed value. This step consumes a one-time physical slot inside the chip, enforcing a hardware-level limit on attempts.
3. Second check with OPTIGA: The transformed value is sent to the OPTIGA Trust M chip. It verifies the value and, if correct, contributes its final secret piece. OPTIGA enforces its own independent attempt limit using a secure, non-resettable counter.
4. Wallet access granted: Only with the final piece from OPTIGA can the MCU assemble the key to decrypt your wallet. This key exists only for a moment in memory and is never stored.

Device authenticity verification

Trezor Suite proves your Trezor Safe 7 is genuine using a cryptographic check that require the certificate and keys stored on the device’s secure elements.

• TROPIC01: Stores and protects part of the device identity and performs signed challenges to prove the chip and firmware are authentic.
• OPTIGA Trust M: Provides an additional protected identity store and cryptographic checks.
• MCU (main microcontroller): Coordinates the exchange. It verifies responses from both secure elements against SatoshiLabs’ public keys, so a cloned or swapped component fails verification.

Secure randomness for wallet creation

When you create a new wallet, TROPIC01 provides strong hardware randomness through its True Random Number Generator (TRNG) and Physical Unclonable Function (PUF).

This entropy is used to generate your wallet backup, ensuring your recovery seed and private keys are unique and unpredictable.

Defense in depth

The Trezor Safe 7’s dual secure elements complement each other to create layered protection.

• Independent limits: TROPIC01 enforces attempt limits through , while OPTIGA uses a in secure memory.
• Tamper detection: Both chips contain voltage, temperature, and laser sensors that can block operations or wipe secrets if tampering is detected.
• Resilient coordination: The MCU manages communication but can’t override chip-level protections. If one chip fails or is tampered with, the other still enforces its limits.

Summary

The dual secure element design in Trezor Safe 7 combines transparency, certification, and hardware resilience.

TROPIC01 and OPTIGA Trust M work together to verify authenticity, enforce PIN limits, and create secure randomness for your wallet backup.

This multi-layered approach makes Safe 7 one of the most tamper-resistant and verifiable hardware wallets available.