Freescale's new MCZ33812 analog integrated circuit delivers new performance in small internal combustion engines

Demand for low-cost two- and three-wheeled vehicles is increasing in emerging markets such as China, India and Brazil. These small engines – especially the vaporized two-stroke design, which represents the mainstream of small motors in Asia – are the main source of air pollution. The harmful gases emitted by a three-wheeled taxi with a two-stroke engine are equivalent to the sum of about 50 modern cars.

Governments are implementing strict regulations requiring motorcycle and outdoor equipment manufacturers to design small engines that burn cleaner. Emerging markets for motorcycles are adopting emission standards similar to Euro 3. The US Environmental Protection Agency (EPA) has also issued strict emissions regulations for small engines. According to the Outdoor Grid Equipment Industry Association survey, when the EPA Phase III standard is fully realized in the United States in 2015, it is expected that the harmful emissions from small gasoline engines will be reduced by 95% compared to the 1997 level.

At the same time, in the face of worldwide emission regulations and rising gasoline prices, the small engine market is shifting from a mechanical carburetor system to a cleaner and more efficient electronically controlled and electronically controlled fuel injection (EFI) system. To address the global need for these eco-friendly designs, Freescale has combined highly integrated analog devices with 16-bit microcontrollers (MCUs) to provide a cost-effective platform solution ideal for small engine control .

The platform consists of the MCZ33812, an advanced analog integrated circuit optimized for controlling fuel and spark and electronic fuel injection systems in EFI, and Freescale S12 microcontrollers (MCUs). The integrated small engine control platform helps reduce harmful emissions, reduces system complexity, reduces material usage and manufacturing costs, and speeds time-to-market.

Freescale's small engine control applications include small displacement two- or four-stroke engines such as motorcycles, mopeds, scooters and three-wheeled taxis. The platform is also ideal for small engine designs for many outdoor power equipment such as lawn mowers, garden tractors, trimmers, edgers, chain saws, snow blowers, leaf blowers, tillage machines, generators, and exterior motors. .

For small engine manufacturers, the most feasible way to meet more stringent government mandatory emissions regulations is to use electronic ignition, electronic carburetor and final EFI engine electronic control. Implementing an EFI system on a small engine can help reduce up to 65% of carbon dioxide, 35% of hydrocarbons, and 35% of nitrogen oxide emissions, respectively, compared to carburetor systems. The small engine with EFI also increased horsepower and increased the number of miles per unit of gasoline.

The widespread introduction of advanced electronic controls for small engines requires highly integrated and economically affordable components. Freescale's new MCZ33812 analog IC represents a breakthrough in this market. The device combines a voltage regulator, injector, driver and ignition pre-driver, as well as relay and lamp drivers, a watchdog timer, a reset generator, etc., to optimize small engine control. Supported by Freescale's SMARTMOSTM technology, this superior integration reduces engine components by up to 12 individual components and streamlines the board area for engine manufacturers while helping customers enhance the quality and reliability of their products.

To help the small engine market move from mechanical/carburetor-based systems to electronic control and fuel injection, Freescale offers integrated system solutions featuring hardware/software reference designs to accelerate the development process. Freescale's finished MCZ33812 reference design is based on the MCZ33812 and S12P microcontrollers to evaluate a two-chip solution and simulate a complete small engine electronic control unit (ECU). Freescale also offers optimized software device drivers and engine control software for small displacement designs. The reference design enables inspection engineers and ECU hardware and software designers to work in parallel, streamlining the development process and speeding time-to-market.

The S12/S12X MCU family is the most widely used 16-bit architecture in the automotive electronics market. The MCZ33812 IC and S12P MCU provide an ideal combination for small engine control designs. The S12P offers the performance benefits of a 16-bit MCU while supporting entry-level pricing, low power, electromagnetic compatibility (EMC) and code size efficiency for 8-bit MCUs. The scalable S12P family offers a number of price/performance options and provides a smooth migration path to the powerful S12XS series and S12XE devices with XGATE technology for improved performance. This compatibility allows developers to upgrade their small engine settings as their flash and performance requirements increase.

· 1 fuel injector low-end driver (current limit: 4.0 A typical)

· 1 relay, fuel pump or second injector low-end driver (current limit: 4.0 A typical)

· 1 low-end driver (current limit: 1.5 A typical)

· 1 ignition pre-driver with independent high-end and low-side outputs