Renesas is a Japanese semiconductor manufacturing giant within the IoT industry. With operations in 20 countries, they’re one of the biggest producers of microcontrollers in the world.

Moreover, Renesa MCUs/MPUs and WiFi modules are extremely user friendly. They’re designed to enable easy connection from an embedded system to cloud servers and RTOS platforms such as Amazon Web Services (AWS), Microsoft Azure, and more.

The modules enable integrating large-capacity flash memory and have a robust support system that helps reduce both development time and costs. The WiFi modules are able to interface to any Renesas IoT MCU through SPI or UART interface and comes with a free WiFi module API library optimized explicitly for Renesas.

That’s all well and good, but which Renesas microcontroller/microprocessor or WiFi module is best for your IoT needs? We’re going to break these down to help you find the right one.

Renesas MCU/MPUs

Renesas MCU and MPUs are separated into two different product lines:

• Renesas Core
• Arm Core

Firstly, we’re going to look at the MCU’s available in the Renesas Core line.

RX

Like most of Renesas MCUs, the RX is not just one microcontroller – it’s a family of four product series 32-bit MCUs. These include:

• RX700 series – This is the flagship product from the RX series. It offers up to 4MB of flash and 1MB of RAM. On top of that, this nifty MCU has an operating frequency of 240MHz, making it the highest-performing MCU of the RX product series. It can be used for multiple industrial applications, including robots, smart meters, and HVAC controllers.
• RX600 series – This microcontroller is referred to as the ‘mainstream’ choice by Renesas. However, it’s performance levels are still comparable to the RX700. It also offers 4MB of flash and 1MB of RAM. However, its operating frequency is slightly lower at 160MHz.
• RX200 series – This MCU has the best balance between both power efficiency and high performance. It provides up to 1MB of flash and 96KB of RAM. Its operating frequency is up to 80MHz. This spec makes it a good microcontroller for wearable healthcare devices and lower power industrial products, such as power meters.
• RX100 series – This is the entry-level 32-bit MCU of the RX series. The RX100 is designed for ultra-low-power consumption, with up to 512KB of flash and 64KB of RAM. This is more likely to be used in consumer electronics rather than in the business world.

These MCUs are the best microcontrollers if your primary concern is power efficiency.

RL78

On the flip side of the RX700 series, the RL78’s specifications are geared towards being as low power as possible.

The RL78’s ultra-low power consumption is highlighted by its CPU operation being 45.5 μA /MHz, and it’s STOP mode at a meager 560 nA. Moreover, the family of 8/16-bit MCU has an array of impressive built-in features, including:

• High-speed on-chip oscillator
• Background operation data flash capable of 1 million rewrites
• A temperature sensor

RH850

The RH850 is Renesas’ latest automotive microcontroller. This family of automotive MCUs provides functional safety and embedded security features that are essential for the requirements of modern and advanced automotive IoT applications.

You can learn more about the RH850’s features here.

That covers the MCUs from Renesas Core. We’re now going to assess the Arm Core line.

RZ (MPU)

The RZ family are the first microprocessors (MPUs) on this list. These high-end 32 and 64-bit MPUs are at the forefront of crafting solutions for the smart society we’re all moving towards.

The RZ series can be used in several different industries, but which series is best for your application? Here’s a shorthand guide below:

• The RZ/A series – This is best for display systems and display connectivity. The RZ/A2M, in particular, offers ten times the image processing ability of your average MPU.
• The RZ/T series – If you’re looking for industrial ethernet, the RZ/T1 is best suited for motor control connectivity.
• The RZ/G series – For 3D Graphics and HD video display, check out the RZ/G series. The RZ/G2H offers up to 35,600 DMIPS with quad-core Arm® Cortex®-A57 (1.5 GHz) and quad-core Arm® Cortex®-A53 (1.2 GHz).
• The RZ/N Series – This series is best for industrial networks and human-machine interfaces.

You can find a more detailed breakdown of the different RZ microprocessors available here.

RA

The Renesas Advanced (RA) 32-bit MCUs are industry-leading 32-bit microcontrollers that incorporate the Arm Cortex-M Core. These secure, flexible, and low power consuming MCUs can be adapted to most embedded systems with relative ease.

There are four different MCUs in the RA Product series. And while they’re relatively similar in DNA, they have a few different features. We’ve included a handy table to differentiate below:

RE

The RE Family is based on the Silicon on Thin Buried Oxide (SOTB™) process technology. It combines extremely-low current consumption with devices in both active and standby mode with extremely-fast CPU operation (64MHz) at low voltage (1.62V).

These EMBC certified MCUs can extend battery life and offer high performance for small batteries and energy harvesting power supplies that can supply only a small amount of current.

This makes these microcontrollers suitable for a number of different IoT applications, including:

• Hybrid watches
• Smart homes/buildings
• Smart agriculture

For more information on choosing the right MCU for your project, read our Guide to Microcontrollers for IoT. This explains all your options and what you need to consider.

Renesas WiFi Modules

Now that we’ve reviewed the different MCUs/MPUs available from Renesas, we’re going to look at the different IoT WiFi modules they have to offer.

Renesa partners with various companies to provide easy to use WiFi solutions. These also provide key WiFi components integrated into a single module, including:

• Baseband
• Radio
• Power amplifier
• Antenna

Renesas sell all of their WiFi modules as part of the Renesas WiFi cloud connectivity kit, but which kit is right for you? Let’s take a look at the different options available.

RX231

The first WiFi Cloud Connectivity Kit is the RX231. This is a great all-rounder. It uses the RX200 series microcontroller we mentioned earlier and includes a PMOC-mounted 3-axis MEMS accelerometer. This makes it easy for users to configure the kit and stream real-time data to the cloud. It also includes a vibration monitoring demo.

The RX321 kit comes with these items:

• 54 MHz RX231 MCU board with 4 PMOD connectors
• E1/E2 Lite header for J-Link support
• GT202 Wi-Fi module using Qualcomm QCA4002 low energy Wi-Fi 802.11a/b/g/n SoC
• PMOD-mounted 3-axis MEMS accelerometer
• Arduino Shield Socket
• USB Type B connector for power and USB 2.0 device interface
• Quick Start Guide
• Free Renesas IoT Sandbox Cloud account
• Smart Machine demo with vibration monitoring

RX111

The connectivity kit for the RX111 is a useful platform for developing IoT applications on the RX111 32-bit microcontroller. This is a good kit helping IoT hobbyists to learn – highlighted by the included Smart Garage Door IoT demo – but probably not overly useful for businesses.

The kit includes:

• RX111 32-bit MCU board with 4 PMOD connectors and JTAG for debugging
• Longsys GT202 PMOD Wi-Fi module using Qualcomm QCA4002 low energy Wi-Fi single-band 802.11a/b/g/n SoC
• USB Cable
• Quick Start Guide
• Pre-programmed with Micriµm’s Spectrum RTOS kernel and components, and the company’s “Smart Home end-to-end IoT demo”
• Pre-configured for Medium One’s IoT Cloud with Data Intelligence platform

Other WiFi Modules and Connectivity Kits Available

There are a couple of other connectivity kits available from Renesas. These include the Amazon Web Services (AWS) Wi-Fi Cloud Connectivity Kit and the Renesas IoT Sandbox powered RX65N Kit.

While these are great options for those looking to experiment or learn more about IoT, if you’re after long-term b2b IoT solutions, it might be best to look for WiFi modules elsewhere.

If you’re looking for more advice on how to choose the best IoT WiFi Module, check out our guide here.

Bottom Line

When looking for MCUs or WiFi modules, it’s a good idea to go with a tried and tested manufacturer. Naturally, this makes Renesas an appealing option.

We’ve also produced guides on other popular MCU and WiFi module manufacturers, including:

• A guide to NXP IoT WiFi Modules, Dev Boards & Rapid Prototyping Kits
• A guide to Microchip WiFi Modules and Development Boards for IoT
• A guide to Texas Instruments WiFi Modules and Development Boards for IoT
• A complete guide to ESP8266 for IoT
• A complete guide to ESP32 for IoT