Microchip Technology AT97SC3205-X3A15-10

Overview

AT97SC3205-X3A15-10 from Microchip Technology (formerly Atmel) is a TCG-compliant Trusted Platform Module (TPM) 1.2 security IC implementing hardware-based cryptographic functions including FIPS-140-2 certified RNG, AES, SHA, and RSA engines. It integrates an AVR RISC microprocessor, 2066-byte NV user storage, and SPI interface up to 45 MHz, deployed in PC client platforms for secure boot, key attestation, and platform integrity verification.

For engineers reviewing the AT97SC3205-X3A15-10 datasheet, AT97SC3205-X3A15-10 pinout, AT97SC3205-X3A15-10 application, or AT97SC3205-X3A15-10 equivalent, key selection considerations include TCG 1.2/TIS 1.3 compliance, SPI timing at 24–33 MHz typical PC range, industrial temperature support (−40°C to +85°C), and dual-package availability (28-pin TSSOP / 32-pad QFN).

Technical Context

The AT97SC3205-X3A15-10 implements a dedicated TPM 1.2 stack with hardware-accelerated asymmetric crypto (RSA key generation and signing), integrated FIPS-140-2 validated RNG, and on-chip EEPROM for persistent RSA key storage. Its SPI interface operates with active-low PIRQ#, CS#, CLK, and RST# signals, supporting TCG PC Client-specific command protocols.

Internal architecture combines an 8-bit AVR RISC CPU, SRAM, crypto engine, physical security circuitry, and dynamic memory management for multi-key caching-requiring no host intervention for TPM_FlushSpecific or TPM_LoadKey2 operations. The device enters low-power mode automatically during idle states without system control.

Key Specifications

Pinout & Package

AT97SC3205-X3A15-10 is offered in two RoHS-compliant, lead-free packages: 28-pin thin TSSOP (28X1) and 32-pad very thin QFN (32M3). Both support industrial temperature range and share identical pin functionality; NC pins are unconnected and may be left floating or tied to GND/VCC per design discretion.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar TPM security module applications.

Compared with Infineon SLB9670 and Nuvoton NPCT750, the AT97SC3205-X3A15-10 delivers validated FIPS-140-2 cryptographic primitives and proven TPM 1.2 interoperability for legacy PC platforms, while offering industrial temperature support and dual-package flexibility unmatched by either alternative.

Availability

AT97SC3205-X3A15-10 is available at Aetrix Electronics and suitable for secure boot authentication, enterprise device attestation, and hardware-based disk encryption requiring stable component supply across industrial and commercial computing platforms.

Supply support for AT97SC3205-X3A15-10 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

Microchip Technology acquired Atmel in 2016 and maintains its trusted computing product lines, delivering secure microcontrollers and dedicated security ICs for embedded and PC applications.

The AT97SC3205-X3A15-10 belongs to Atmel's TPM security IC family, designed specifically for integration into PC motherboards and industrial systems requiring hardware-rooted trust, cryptographic acceleration, and TCG-compliant platform integrity assurance.

FAQ

What is the primary compliance standard met by the AT97SC3205-X3A15-10?

The AT97SC3205-X3A15-10 complies fully with the Trusted Computing Group (TCG) Trusted Platform Module (TPM) Specification Version 1.2 and the PC Client-Specific TPM Interface Specification (TIS) Version 1.3. This ensures interoperability with BIOS/UEFI firmware and operating system security stacks such as Windows BitLocker and Linux tpm-tools. The AT97SC3205-X3A15-10 also holds FIPS-140-2 certification for its RNG, HMAC, AES, SHA, and RSA engines - a requirement for many government and regulated enterprise deployments.

Does the AT97SC3205-X3A15-10 support both commercial and industrial temperature ranges?

Yes, the AT97SC3205-X3A15-10 is qualified for industrial operation from −40°C to +85°C, making it suitable for ruggedized computing equipment, industrial PCs, and embedded systems exposed to wide thermal swings. Its internal EEPROM and physical security circuitry are characterized across this full range to ensure reliable key storage and tamper detection performance. The AT97SC3205-X3A15-10 does not require derating or special thermal management under these conditions.

What SPI interface timing parameters define the AT97SC3205-X3A15-10's operational window in PC systems?

The AT97SC3205-X3A15-10 supports SPI clock speeds up to 45 MHz but specifies a typical PC operating range of 24–33 MHz - aligned with standard motherboard SPI bus timing budgets and TCG TIS 1.3 timing constraints. Critical timing includes minimum SPI_RST# pulse width of 2 μs and strict setup/hold requirements for MOSI relative to SPI_CLK edges. The AT97SC3205-X3A15-10 also requires SPI_CS# assertion before clock activation to prevent command corruption.

How is the 2066-byte NV user storage in the AT97SC3205-X3A15-10 utilized in practice?

The 2066-byte NV user storage in the AT97SC3205-X3A15-10 is allocated outside the standard TPM-defined NV index space, allowing OEMs to store platform-specific credentials, custom certificates, or attestation policies without consuming limited TPM-managed indices. It is accessed via Atmel-specific TPM commands documented in the "Atmel Specific TPM Commands Reference Guide" and persists across power cycles. The AT97SC3205-X3A15-10 manages this space independently of host OS intervention.

What physical security features does the AT97SC3205-X3A15-10 implement to protect against tampering?

The AT97SC3205-X3A15-10 incorporates dedicated physical security circuitry that monitors voltage, frequency, temperature, and probe activity. Upon detecting out-of-spec conditions - such as voltage glitching, clock manipulation, or invasive probing - it triggers immediate zeroization of all sensitive cryptographic keys stored in EEPROM and SRAM. The XTamper pin (shared with TestBI/GPIO) provides an external tamper detect input, active high, enabling integration with chassis intrusion switches or environmental sensors. These protections satisfy TCG physical protection requirements for Level 2 TPM devices.