Twenty years ago, who would have considered security issues when using MCUs for low-power products?
But now it’s different. As the Internet of Things and automation become part of our daily lives, advanced security has become increasingly important in low-power devices. Many modern MCUs integrate dedicated security features and technologies to meet the security needs of low-power devices.
Renesas Electronics RA4L1 MCU: The RA4L1 utilizes Renesas’ advanced low-power process technology, supporting operating voltages as low as 1.6V and standby currents as low as 1.65μA. It features an 80MHz Arm® Cortex-M33® core, integrates TrustZone® technology, and is equipped with the RSIP-E11A security engine, which includes hardware accelerators for symmetric and asymmetric encryption algorithms, a true random number generator, and provides security functions such as key wrapping, secure key injection and updates, and device lifecycle management, making it suitable for low-power security-sensitive applications like smart meters and smart locks.
Renesas Electronics RA0L1 MCU: The RA0L1 features ultra-low power characteristics, based on the Arm® Cortex®-M23 core, with a maximum frequency of 32MHz, operating current as low as 2.9mA, and only 0.92mA in sleep mode. Its fast wake-up function allows the RA0L1 MCU to remain in standby mode for longer periods, with power consumption reduced to a negligible 0.25μA, achieving a 90% reduction in current consumption compared to other solutions. Previously, we shared related content: Low-cost ultra-low-power touch MCUs are on the rise.
Renesas Electronics RA4C1 MCU: The RA4C1 employs proprietary low-power technology, with operating mode power consumption of only 168μA/MHz and standby current as low as 1.79μA. It features the RSIP-E31A security engine, supports 256-bit hardware unique keys and a true random number generator, and includes key management functions capable of generating encapsulated keys, supporting SHA algorithms, AES hardware acceleration, and ECC with key lengths of up to 384 bits. It has also received PSA Level 1 certification and complies with the European Cyber Resilience Act (CRA) compliance extension.
Today, we will focus on the RA4L1.
RA4L1 Block Diagram
The RA4L1 series MCUs are feature-rich, optimized for low-power applications, with a wide range of communication interfaces and rich analog and system functions.
One of the key features of the RA4L1 is the segment LCD controller, which allows battery-powered devices and other consumer electronics and appliances to operate in the lowest power mode while driving up to 384 segments of LCD.
Here is a simplified block diagram of the segment LCD controller and a table showing the number of available segments in each package.
Simplified Implementation of Segment LCD Controller
Maximum Number of LCD Signals on RA4L1 Package Types
Features of RA4L1:
The RA4L1 is a low-power microcontroller introduced by Renesas Electronics. In addition to its low power consumption, high performance, and rich peripherals, it also requires careful consideration of security for every application in the future to protect data and secure communication. The powerful security IP (RSIP) is designed to help you achieve this. The RA4L1 implements a wide range of advanced security features, including:
1
RSIP-E11A Security Engine
2
Key Wrapping
3
Secure Key Injection and Updates
4
Device Lifecycle Management (DLM) Status
5
Authentication and Protection Levels
6
Secure Factory Programming
7
Arm TrustZone
8
Tamper Detection
9
Lockable Flash Memory
The core of the RA4L1 security features is the RSIP security engine, which integrates the RSIP-E11A security engine, supporting true random number generation (TRNG), unique ID, AES, ECC, SHA, and other encryption algorithms. It provides key wrapping, secure key injection and updates, device lifecycle management, and other security functions to effectively protect the security and integrity of data.
It is an isolated subsystem within the MCU. The security engine is protected by access management circuits that shut down the encryption engine in the event of illegal external access attempts, preventing attacks such as differential fault analysis. The encryption engine includes hardware accelerators for symmetric and asymmetric encryption algorithms, as well as various hash and message authentication codes. Inside the security engine is a component of the MCU hardware root key used to store and inject other keys, which we will see later. It also contains a true random number generator with an entropy source compliant with SP800-90B standards and NIST-certified DRBG algorithms.
RSIP-E11A Security Engine Diagram
The security engine contains internal RAM for operations involving sensitive materials (such as plaintext keys). This RAM is inaccessible outside the security engine. The RSIP security engine can be combined with higher-level security structures in the Renesas Flexible Software Package (FSP). The FSP is an enhanced software package designed to provide user-friendly, scalable, high-quality software for embedded system design using any RA Arm microcontroller, ensuring software compatibility across the entire series. The embedded drivers and security primitives implemented in the FSP provide a complete solution for embedded data protection and identity verification.
RA Flexible Software Package (FSP) | Renesas Electronics
https://www.renesas.cn/zh/software-tool/ra-flexible-software-package-fsp
These features make the RA4L1 very suitable for a wide range of applications requiring low-power operation, multiple communication functions, LCD display driving, and especially security features, including:
1
Audio Systems
2
Access Control Systems
3
Consumer Products
4
Industrial and Utility Metering Applications
5
Security Systems
6
Smart Locks
7
Industrial Sensors
More Information
For more information, including documentation and videos, please visit the RA4L1 product page. To learn more about how to protect products from concept to production, including certification and software listings, please visit the IoT Security page.
RA4L1 – Low-Power MCU Based on 80MHz Arm Cortex-M33 with TrustZone, Segment LCD Controller, and Advanced Security Features | Renesas Electronics
https://www.renesas.cn/zh/products/ra4l1
Renesas Electronics IoT Security Solutions | Secure Connected Devices | Renesas Electronics
https://www.renesas.cn/zh/key-technologies/security/iot-security
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