Efforts to grapple with environmental issues have already grown to a global scale. As a manufacturer of semiconductor devices, the Renesas Group works hard to translate the technology it possesses into the most effective environmental measures possible, both in the development of new products and when proposing applied technologies for them (application ideas). We feel that these new products and application systems incorporating eco-friendly technology must be environmentally friendly solutions in addition to providing the marketplace with confidence, comfort, and dreams.
As examples of this commitment, we present here examples of the low-power technology used in the design of our advanced semiconductor devices and of low-power technology for application systems employing these devices.
In addition, we introduce several of our microcontroller products（V850 Series, 78K0R Series, 78K0 Series, RX Family, R8C Family, M16C Family, SuperH Family, SH-Mobile, SH-MobileR) and power devices as exemplars of eco-friendly semiconductor devices.
Finally, we take a closer look at Renesas power devices designed with the environment in mind.
Low-Power Technology in Advanced Semiconductor Devices
Here we will examine low-power technology incorporated into the advanced semiconductor devices themselves. To build an eco-friendly product, it is necessary first of all to use semiconductor devices that are energy efficient in their own right. Low-power technologies typically used by semiconductor manufacturers to reduce the power consumption of their products include items 1) to 5) below. Keep in mind that other new low-power technologies are appearing all the time, and it is likely that the trend toward even greater power efficiency will accelerate in the years ahead.
1) Applying Advanced Ultrafine Process Technology
The use of advanced ultrafine process technology enables operation at a lower power supply voltage, while the use of ultrafine patterns and alternate trace materials can lower the power consumption by reducing the parasitic capacitance load. However, there are concerns that using a finer process node will increase leak current. In response, new technologies such as the use of high-k materials make it possible to suppress leak current.
2) High-Density Cell Design
Another way to achieve reduced power consumption is to employ a high-density design approach in which every effort is made to eliminate the redundant portions of the logic circuit cells and to reduce parasitic capacitance through optimal transistor design.
3) Low-Power Control Technologies at the Circuit Level
(a) On-Chip Power Supply Control Technology
- Power Supply Matching Operating Mode:
- This technology checks each of the device's internal circuit blocks successively to determine if it is active or inactive, and cuts off power to, or puts into standby mode (in which power is supplied to only some elements), the circuit blocks in the inactive state.
- Dynamic Voltage Supply Matching Operating Frequency:
- This technology controls the power supply voltage for each of the device's internal circuit blocks to match its required operating speed.
- Voltage Control to Match Processing Load:
- This technology allows the device to operate on low voltage and low current most of the time, but switches dynamically to high voltage and high current when the processing load increases.
- Adaptive Voltage Supply:
- This technology aims to suppress wasted power by adjusting the power supply voltage to what is appropriate to match variations in the operating ambient temperature and the characteristics of individual devices.
(b) Clock Supply Control Technology
- Clock Supply Matching Operating Mode:
- This technology checks each of the device's internal circuit blocks successively to determine if it is active or inactive, and cuts off supply of the clock signal to the circuit blocks in the inactive state.
- Clock Frequency Control to Match Operating Mode:
- This technology uses on-chip clock generator and clock divider circuits to enable production of multiple clock frequencies, and supplies to each of the device's internal circuit blocks the most appropriate clock frequency to match its operating mode. The idea is to eliminate as far as possible the supply of clock frequencies that are unnecessarily high.
4) Multi-Core CPU Technology
In the past, approaches such as advanced semiconductor fabrication processes, higher clock frequencies, and innovative new processor architectures were pursued continuously in order to boost CPU performance. However, there are limits to the extent to which performance can be boosted while ignoring power consumption, and other problems exist as well from an environmental viewpoint. Nowadays, the emphasis is on boosting performance while maintaining low power consumption. A shift is underway from the notion of pursuing higher performance by continuing to raise the clock frequency to approaches that increase performance while keeping power consumption low. Examples of such approaches, which do not require ever higher clock frequencies, include parallel processing architectures that allow the CPU to handle multiple instructions at the same time and parallel processing using multi-CPU configurations employing more than one CPU core.
5) Advanced Compact Package Technology
- Smaller Packages:
- As package sizes shrink, efforts are being made to reduce the length of the internal interconnects between the chip and the package leads, and the length of the package leads themselves, in order to reduce load capacitance and thereby cut power consumption. Nevertheless, with more compact packages it is still necessary to calculate the heat tolerance and provide some margin as needed.
- SiP (System/Solution in Package) Technology:
- Integrating multiple chips into a single package not only allows more efficient use of space, it also makes it possible to keep the interconnects between chips extremely short and thereby reduce the load capacitance, which can bring a substantial reduction in power consumption. Nevertheless, though adoption of SiP technology brings real gains, it is still necessary to calculate the heat tolerance and take additional measures to provide a margin in some cases.
Articles on Low-Power Technology from Renesas
Vol. 23 of Renesas Edge, our company's technology information magazine, contains a special feature entitled "Technology Initiatives Produce Gains in Energy Conservation." You can view it by clicking the link below.
Mobile Applications, Where Power Consumption Restrictions Are the Industry's Most Demanding:
Extending Our Advanced Technologies to a Diverse Range of Fields
Our SH-Mobile processors enable mobile phones, which are compact and run on batteries, to deliver extended battery life while accommodating power-hungry multimedia applications such as music playback or One-Seg TV broadcast reception. Developing the SH-Mobile Series has been a long-running battle against power consumption, with new technologies being developed and commercialized with each new device generation. Now we are transplanting these technologies to our other product lines, such as the R8C Family of microcontrollers, which enjoy a high market share in household appliances and consumer electronics. In this way we are helping to create a whole new product category of eco-friendly household appliances.
Multi-Core Technology for Enhanced Performance and Low Power Consumption:
Meeting Automakers' Need for Energy Efficiency with the SuperH Family
The additional power consumption that typically accompanies higher processing performance is becoming a problem in the automotive sector as the number of microcontrollers in a typical vehicle continues to grow. Greater power consumption means more heat generation, which can lead to overheating in ECUs, car navigation systems, and other electronics. To solve this problem Renesas is working to improve the processing capacity per unit of power consumption of the SuperH microcontrollers widely used in automotive applications. In particular, we were among the first semiconductor manufacturers to use multi-core technology in automotive IT systems to deliver significantly better performance while keeping power consumption low.
Renesas Microcontroller Products with Low Power Consumption
Renesas microcontroller products help our customers develop more eco-friendly systems.
Renesas has a large share of the microcontroller market, and from early on we have been focused on technologies for reducing the power consumption of our products. Here we feature some of the low-power technologies used in Renesas microcontrollers for applications ranging from household appliances and consumer electronics to industrial equipment.
An excellent example of an eco-friendly device, the V850ES/Jx3-L provides 32-bit performance with power consumption typical of a 16-bit microcontroller. The next-generation 40 nm models will retain the excellent power efficiency of their predecessors while using virtualization technology and multi-threading to further boost performance and functionality.
The 78K0R/Kx3-L delivers the performance of a low-end 32-bit microcontroller in a 16-bit architecture. Its low-current operation characteristics are among the best in the industry, making it an eco-friendly device that combines speed and low power consumption. It is suitable for a wide range of applications that previously required a 32-bit microcontroller, such as inverter control in refrigerators and the like.
Ideal for battery-powered applications, the 78K0/Kx2-L delivers superior low-power performance even when the A/D converter is operating. Another great eco-friendly feature is the standby current level, which is among the lowest in the industry.
Efforts to Reduce the Power Consumption of the RX Family
The RX600 Series uses the 90 nm process node and incorporates low-power technology to achieve better power efficiency than comparable earlier microcontrollers. Power consumption is reduced both during normal operation and in low-power mode, making the RX600 Series suitable for a variety of embedded applications.
RX: High Performance and Low Power Consumption
The RX600 Series achieves low current consumption of only 50 mA when operating at 100 MHz. This is equivalent to four times the CPU performance at the same level of current consumption, compared to earlier microcontrollers. In other words, the RX600 Series can deliver the same performance as earlier products while consuming half as much current.
Reduced Current Consumption to Match the Operating Mode
The RX600 Series has multiple low-power modes to enable it to support embedded applications. In deep software standby mode, which has the lowest current consumption, power consumption is reduced 94% compared to earlier microcontrollers.
Use of RX600 Series in Eco-Friendly Household Appliances
The RX600 Series product lineup is ideal for eco-friendly household appliances. In particular, the RX62T Group simplifies implementation of inverter control, which is essential for cutting the power consumption of electric appliances (air conditioners, clothes washer/dryers, refrigerators, heat pump water heaters, etc.), while the RX62N Group and RX621 Group are suitable for home network systems designed to "visualize" power usage. Renesas also plans to release RX600 Series products for smart grid applications, which are expected to achieve wide adoption moving forward.
Low-Power Technologies Such as Low-Voltage Operation and On-Chip Power Control: R8C Family for More Eco-Friendly Household Appliances and Consumer Electronics
The R8C Family aims to enable use of smaller batteries by reducing current consumption and supporting low-voltage operation. It advances the standard for low-power operation in all the microcontroller's operating modes. In particular, the R8C/Lx Series is a compact 16-bit microcontroller that incorporates the same type of power control circuit used in high-performance microcontrollers for mobile phones and the like, enabling it to achieve even better energy efficiency.
In addition, a flash memory low-power operation mode is supported. Writing to, erasing, and reading the flash memory requires a low voltage of only 1.8 V, enabling use of small-capacity batteries and contributing to lower power consumption.
Efforts to Cut Current Consumption During Operation
Two processes are used to fabricate the products in the R8C Family: an ultrafine process designed for high performance and advanced functionality and a low-power process aimed at reduced power consumption. R8C Family products employing the latter process deliver the best low-power-consumption performance in the industry in high-speed operating mode (active mode): 150 µA/MHz. This represents a reduction in power consumption of roughly half compared with earlier models, making these microcontrollers truly eco-friendly products.
Efforts to Cut Current Consumption in Standby and Clock-Only Modes
Two processes are used to fabricate the products in the R8C Family: an ultrafine process designed for high performance and advanced functionality and a low-power process aimed at reduced power consumption. R8C Family products employing the latter process deliver the best low-power-consumption performance in the industry in power-off mode: 20 nA. This is equivalent to about 1/100 the power consumption of earlier models, making these microcontrollers ideal for eco-friendly applications such as electronic switches.
Achieving Eco-Friendliness with High Performance, Many Integrated Functions, and High EfficiencyThe SH7260 Series, which belongs to the SuperH RISC Engine Family, is an eco-friendly device suitable for use in audio and display systems. The large-capacity on-chip RAM helps reduce the overall number of system components. In addition, low-leak RAM and power supply isolated shutoff technology make it possible to reduce current consumption in the system standby state to a few tens of µA or less.
- High Performance
- Low power consumption thanks to architecture optimized for performance per unit of frequency
- Many Integrated Functions
- Peripheral functions optimized for specific applications
- Lower board cost
- High Efficiency
- Ability to handle sophisticated algorithms
- Integration of functions using software
SH-Mobile and SH-MobileR
The Evolution of the Cellular Phone by ECO (Super Low Power Consumption)SH-Mobile is a family for eco-friendly mobile phone by delivering low-power-consumption. In addition to lower power consumption during normal operation, a rich power management system incorporating technologies such as power supply isolated shutoff lowers the standby current to µA range. SH-MobileR is another family derived from the SH-Mobile family which also matches in the industry instrument. SH-Mobile and SH-MobileR help make embedded systems more eco-friendly.
Renesas Power Devices Designed with the Environment in Mind
1) Delivering High Power Conversion Efficiency to Power Supplies for All Types of Equipment with Critical Conduction Mode Interleaved PFC ICs and Low-Loss MOSFETs
Every type of equipment that runs on electricity has a power supply, which converts power from an AC commercial power source or a battery into DC power with a specified voltage. Increasing the conversion efficiency by even 1% translates directly into reduced power consumption and energy savings. That's why from early on Renesas has supplied devices that help our customers boost the energy efficiency of their products, such as critical conduction mode interleaved PFC ICs for improving the power factor or battery control ICs for highly precise battery charge remaining detection. We are also working to further improve compactness and power efficiency by offering power MOSFET products such as 6 mm × 6 mm DrMOS devices employing SiP technology.
2) Power Devices Designed with the Environment in Mind and Their Constituent Technologies
Renesas is engaged in thoroughgoing environmental efforts. Constant advances in the constituent technologies of our power devices deliver improved environmental performance.
Power MOSFET Products for Automotive Applications
Our Power MOSFET products for automotive applications provide exceptionally high quality and reliability along with a 0.25 µm process using the latest trench technology (UMOS4) and new multi-bonding mount technology for the world's best ultralow ion resistance. These products help our customers design systems that use less power and deliver high drive efficiency.