The explosion in the use of electronics by consumers over the last 25 years has been truly remarkable. In the late 1970s, average consumers in a developed country probably had a TV, a Hi-Fi unit, and a VCR in their homes. Today, the same consumers have a digital TV, PC, DVD-recorder, game consoles, set-top box, and may be regularly using portable devices such as mobile phones, digital cameras, MP-3 players, and camcorders.
Following this trend, the home appliance industry has observed an increased adoption of electronics content in consumer white-goods such as washers and dryers, refrigerators, air conditioners, microwave ovens, and portable appliances. The major drivers for this trend include:
- Technology advancement: New technologies such as variable-speed motor control allow appliances to be more energy-efficient, and home networking enables home owners to control and monitor the energy usage of all household appliances that are connected to the same network.
- Consumer desire for improved lifestyle: An emerging trend among upper to middle-class consumers calls for appliances that not only provide basic functions, but also include “cool” features such as touch-screen controls instead of traditional buttons/knobs or an integrated security camera in a kitchen appliance that allows a parent to watch a child playing or sleeping in another room.
- Manufacturer desire to boost market share growth by adding attractive features for product differentiation: To attract the high-end segment of the consumer appliance market, manufacturers look for ways to add “digital life-style” features such as an HDTV built into the door of a refrigerator or an iPod charger integrated in a sleep-sound machine.
Until recently, most home appliance system designs contained microcontrollers (MCUs) to control appliance functions such as display panels, temperature sensors, or motors. However, programmable logic devices (PLDs) have made steady headway into the home appliance markets due to the rapid decline in PLD cost per function.
There are two types of PLDs:
- Field-programmable gate array (FPGA): Device composed of an array of configurable programmable logic cells that can be configured to perform a variety of functions
- Complex programmable logic device (CPLDs): Programmable logic device made up of several simple PLDs with a programmable switching matrix in between the logic blocks. CPLDs typically use EEPROM, flash memory, or SRAM to hold the logic design interconnections
In a home appliance design, because of its programmability, you can use a single Cyclone® FPGA plus a Nios® II embedded processor to replace multiple MCUs in controlling various appliance functions. Figure 1 shows an example of a washing machine system architecture based on a Cyclone FPGA and a Nios II embedded processor. Other examples of Cyclone FPGA and Nios II embedded processor uses in home appliances are shown in Figures 2 and 3.
Figure 1. FPGA Functions As a Washing Machine Control Unit
Figure 2. Touch Screen Display Implementation with Cyclone III FPGA
Figure 3. Motor Control Architecture Based on a Cylcone III FPGA
It is also possible to use FPGAs to implement an in-home touch-screen display panel that monitors and controls power consumption for all appliances that are attached to the same home network. To demonstrate this capability, Altera, Echelon, PlanetWeb, and SLS have teamed up to provide a proven platform that delivers energy-saving solutions for home owners and appliance manufacturers. The “Energy Aware Appliance” Platform: A New Approach to Home Energy Control white paper contains a detailed description of this evaluation platform.
In addition to FPGAs for large home appliances, there is a trend to employ CPLDs as a companion chip to MCUs or as a replacement for several MCU functions in small, portable home appliance system designs to save bill-of-material (BOM) costs. Figures 4, 5, and 6 show examples where CPLDs act as companion devices for MCUs, providing peripheral extension or bridging functions to MCUs and other devices.
Figure 4. MAX II Provides GPIO Extension Function to an MCU
Figure 5. MAX II CPLD Provides Bridging Function
Figure 6. MAX II CPLD Provides I/O Extension to an MCU
Other popular functions for CPLDs in home appliances include:
- Reduction of system power consumption in portable appliances with zero-power MAX IIZ CPLDs
- Security protection with the ability to enter secured data into CPLD user flash memory
Figure 7 shows an example of an appliance multitouch screen design implemented by a MAX IIZ CPLD.
Figure 7. Multitouch Screen Implementation Based on an Altera CPLD and an Analog Device
Related Links
- Cyclone FPGAs
- MAX II CPLDs
- MAX II design examples
- Nios II embedded processors
- “Energy Aware Appliance” Platform: A New Approach to Home Energy Control white paper (PDF)
- Implementing a Cost-Effective Human-Machine Interface for Home Appliances white paper (PDF)
- FPGAs Enable Energy-Efficient Motor Control in Next-Generation Smart Home Appliances white paper (PDF)
