SDAA461 July   2026 CC2744R7-Q1 , CC2745P10-Q1 , CC2745R10-Q1 , CC2745R7-Q1

 

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Introduction

The CC27xx is a Texas Instruments' wireless microcontroller device family with an integrated hardware security module (HSM) providing hardware-accelerated cryptography. Embedded firmware engineers and security architects can use this document to help design connected products for internet of things (IoT), smart home, industrial automation, and wireless sensor applications where security and energy efficiency are both critical.

This document tests the timing performance benchmark for the CC2745, a TI wireless microcontroller that integrates a dedicated hardware security module (HSM) for accelerating cryptographic operations. The HSM offloads security workloads from the main CPU.

The testing process measured timing data for AES-128, SHA-256, and ECC-256 operations. All timing tests were run using Texas Instruments' SimpleLink™ Low Power F3 software development kit (SDK) version 9.20.00.81 with HSM firmware version 3.4.5 on PG2.0 silicon unless otherwise noted. The results include key recommendations drawn from the testing data and comparisons between HSM hardware acceleration and MbedTLS software.

The data enables design teams to select the appropriate crypto path: HSM hardware for bulk throughput (up to 2.5 times faster at larger payloads) and software fallback for small-packet, latency-sensitive use cases.

Timing Comparison: HSM Hardware vs MbedTLS Software

Measurements were taken on SDK 9.20.00.81 with HSM firmware of 3.4.5 on PG2.0 silicon. The results show that HSM hardware delivers significantly better throughput than MbedTLS software for larger payloads.

Table 1 AES-CBC-128
Data Size Encryption Decryption
HSM HW
(µs)		 MbedTLS SW
(µs)		 SW to HW Ratio HSM HW
(µs)		 MbedTLS SW
(µs)		 SW to HW Ratio
16 bytes 124 34 0.27 × (SW faster at small sizes) 122 84.5 0.69 × (SW faster at small sizes)
128 bytes 124 134.5 1.08 × (HW faster) 123.5 204 1.65 × (HW faster)
256 bytes 127 232.5 1.83 × (HW faster) 125.5 328 2.61 × (HW faster)
Table 2 SHA-256
Data Size HSM HW (µs) MbedTLS SW (µs) SW to HW Ratio
3 bytes 110.5 70 0.63 × (SW faster at small sizes)
65 bytes 109 125.5 1.15 × (HW faster)
252 bytes 110 279.5 2.54 × (HW faster)
Table 3 ECDSA- SECP-256
Op HSM HW (ms) MbedTLS SW (ms) SW/HW Ratio
Signing 23.63 1062 44.94 × (HW faster)
Verification 41.50 4017 96.8 × (HW faster)

Key Findings

The CC2745 HSM provides hardware-accelerated cryptographic operations. The benchmark data produced the following key findings:

  • AES-128 encryption or decryption latency is approximately 124 to 127µs, indicating that the HSM operation restricts the latency rather than the driver interface. SHA-256 can show a similar pattern.
  • Even though ECC-256 signing (approximately 24ms) and verification (approximately 41ms) are the most expensive operations, these operations still outperform MbedTLS software.
  • For larger payloads, HSM hardware outperforms MbedTLS software:
    • AES-CBC encryption is approximately 1.83 times faster at 256 bytes and decryption is approximately 2.61 times faster
    • SHA-256 is approximately 2.5 times faster at 252 bytes
    • At small data sizes (less than approximately 30 bytes), MbedTLS software is faster due to HSM initialization overhead

Overall, the HSM is appropriate for applications requiring bulk cryptographic throughput and ECDSA based signing and verification. For latency-sensitive operations on small data (less than 16–30 bytes), designs can implement a software fallback.