STMicroelectronics STSAFA110DFSPL02

Overview

STSAFA110DFSPL02 from STMicroelectronics is a CC EAL5+ AVA_VAN5 certified secure element IC designed for authentication, secure boot, and TLS handshake acceleration in IoT peripherals and consumables. It implements ECC-256/384 with ECDSA-SHA256/SHA384, supports up to 16 symmetric keys, provides 6 KB configurable EEPROM (30-year retention), and operates from −40 to 105 °C on 1.62–5.5 V supply.

For engineers reviewing the STSAFA110DFSPL02 datasheet, STSAFA110DFSPL02 pinout, STSAFA110DFSPL02 application, or STSAFA110DFSPL02 equivalent, key selection considerations include I²C Fast-mode (400 kbps) interface compliance, secure counter usage monitoring for consumables, preloaded Sigfox/LoRaWAN credentials for LPWAN, and pairing-enabled host secure channel establishment.

Technical Context

The STSAFA110DFSPL02 integrates a hardened secure MCU running a tamper-resistant OS with active shield, environmental monitoring, and fault/side-channel attack protections. Its asymmetric cryptography engine executes NIST/Brainpool ECC key generation, ECDSA signature generation/verification, and ECDH/ECDHE key establishment - all using private keys permanently stored and never exposed outside the die.

It implements a dual-layer security model: host-side command authorization via AES-based C-MAC and cipher keys, plus local envelope wrapping/unwrapping for encrypted storage of host secrets in non-secure memory. The I²C interface uses true open-drain SDA/SCL with no clock stretching, requiring external pull-ups and supporting 7-bit addressing.

Key Specifications

Pinout & Package

STSAFA110DFSPL02 is available in SO8N (4 × 5 mm) and UFDFPN8 (2 × 3 mm) ECOPACK-compliant packages. Both variants share identical pin functions and I²C-based communication architecture.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar secure element applications.

Compared with ATECC608A-TFLXT and SLB9670, STSAFA110DFSPL02 delivers tighter integration for IoT edge devices through its dual-package flexibility, built-in LPWAN readiness, and hardware-accelerated TLS handshake components - reducing host firmware complexity and enabling faster time-to-certification for cloud-connected peripherals.

Availability

STSAFA110DFSPL02 is available at Aetrix Electronics and suitable for USB Type-C power delivery chargers, medical consumables, smart home gateways, and industrial sensor nodes requiring stable component supply across multi-year production cycles.

Supply support for STSAFA110DFSPL02 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, analog ICs, MEMS, and secure elements for industrial, automotive, and consumer markets.

STSAFE-A110 belongs to ST's secure element product line, engineered specifically to provide turnkey authentication, secure boot, and TLS acceleration for resource-constrained IoT peripherals and consumables - eliminating the need for custom security firmware development.

FAQ

What is the maximum I²C clock frequency supported by STSAFA110DFSPL02?

The device supports I²C Fast-mode operation up to 400 kbps, with strict timing compliance verified per Figure 16 in DS13039 Rev 2. It does not support clock stretching, so the host must adhere to setup/hold times without relying on SCL hold arbitration. External pull-up resistors must be sized per bus capacitance to maintain signal integrity at this speed.

Does STSAFA110DFSPL02 require external programming before first use?

No - it ships prepersonalized with a factory-programmed X.509 certificate chain, unique serial number, and ST root CA certificate. Customers can optionally engage ST's certified secure provisioning service for customer-specific key injection, but basic authentication and secure channel setup work out-of-box using the embedded ST CA trust anchor.

Can STSAFA110DFSPL02 operate reliably at 1.62 V supply?

Yes - the device is fully functional across its entire 1.62–5.5 V range, including at minimum VCC. All cryptographic operations, EEPROM writes, and I²C communication meet specifications at 1.62 V and −40 °C, as confirmed in Section 5.2.1 of DS13039 Rev 2. No brown-out detection or voltage scaling is required.

How many secure one-way counters does STSAFA110DFSPL02 support?

The device implements multiple decrement-only secure counters, with allocation governed by the secure operating system's memory partitioning scheme. While the exact count is configurable during personalization, the datasheet confirms support for ≥3 independent counters - sufficient to track usage of multiple consumable types (e.g., ink, printhead, maintenance kit) within a single peripheral.