To get a leg up over their competition, microcontroller chip vendors are rushing to market new devices with the popular 8-bit MCU cores surrounded by a wide variety of peripheral circuitry, an ever increasing amount of flash memory, popular buses structures such as CAN (Controller Area Network), as well as multiple A/D and D/A blocks housed in smaller and smaller packages. Some companies have also designed-in special circuitry for power management and low voltage operation.
There doesn't seem to be any let-up in the rate of new products surfacing in the 8-bit MCU arena as system OEMs continue to replace electromechanical components with highly integrated and very inexpensive microcontroller chips. Automotive electronics, for examples consumes huge amounts of devices for applications ranging from body controllers, immobilizer receivers, occupant detection systems, power steering, to anti-lock braking and stability sensing systems. Imaging systems, industrial controls, medical and scientific instrumentation, wireless base stations, automatic test equipment and a wide assortment of consumer appliances are also targeted applications for latest generation of microcontroller devices.
Among the many vendors chasing after automotive system designers is Microchip Technology (Chandler, Ariz.) which recently launched the newest members of its PIC microcontroller line. Microchip has built-in features in demand by the car companies such as the CAN2.0B interface and higher density flash memory. Automotive engineers have a growing need for cost-effective 8-bit microcontrollers with built-in CAN functionality and flexible flash memory, balanced with a requirement to consume less power and take up less space, said Cheri Keller, product marketing manager for PIC MCUs. The MCUs also have Microchip's on-chip ECAN module, that enables multiple applications to be configured on a single node, with easier implementation to a software protocol bridge from a CAN network and a device to be re-used across different applications.
The units have either 48 Kbytes or 64 Kbytes of flash program memory in a tiny 28-pin package. The flash memory can be programmed "in-car." To meet the power management needs of the market, the new devices also have Microchip's nanoWatt technology, which according to Keller improves battery life, which is a major cause of car failures today. Peripherals can be shut down to conserve power. In sleep mode, typical power consumption is as little as 0.1 microamp.
For details on the line, visit Microchip's MCUs.
Also focusing on its CAN features is Atmel Corp.(San Jose, Calif.) The company's new AT90CAN128 AVR flash microcontroller boasts 16 MIPS processing speed for many CAN networking and industrial applications, including factory and building automation, medical equipment, marine networking and print media. The CAN controller can handle 15 independent message objects, programmable on-the-fly. With a 16 MIPS AVR RISC-engine, 128-Kbyte flash program memory, 4-Kbyte RAM and 4-Kbyte on-chip EEPROM, AT90CAN128 can tackle the most demanding industrial control applications, according to Atmel.
Dual 16-bit, 1 Msps (mega sample per second) analog-to-digital converters are a key feature of Silicon Laboratories (Austin, Tex.) newest 8-bit C8051F06x family that integrates a 25 MIPS 8051 MCU with the dual A/Ds. A two percent accuracy precision internal oscillator, also on-chip eliminates the need for an external crystal or resonator. Silicon Laboratories' is targeting such applications that require high-speed data acquisition, high accuracy, low noise and low power consumption including applications such as imaging systems, industrial controls, medical and scientific instrumentation, wireless base stations and automatic test equipment. Details of the new MCU are shown below.
Another new 8-bit MCU line that has two A/D converters on chip is now available from Royal Philips Electronics (San Jose, Calif.) The LPC935 is the flagship chip of nine new microcontrollers in the LPC900 family for a variety of consumer devices ranging from coffeemakers and washing machines to intelligent toys. The LPC935 bridges the man-machine worlds, enabling the ADC and DAC conversions between the analog and digital computing worlds, it was noted.
With two A/D converters, the LPC935 can simultaneously convert and read data in two channels, providing designers the advantages of real-time data analysis, such as simultaneously reading voltage and current measurements. The LPC935 converts these signals in less than four microseconds.
Each of the new LPC900 family MCUs -- the LPC904, LPC915/6/7, LPC924/5 and LPC933/4/5 - allows customers the flexibility to select A/D conversion or high-speed digital-to-analog (ADC/DAC) output. By offering ADC/DAC functionality, customers will no longer need to use separate ADC or DAC on their printed circuit boards (PCBs) that are already integrated into the LPC900 family, according to Philips. The new microcontrollers also offer customers the ability to define data reading boundaries for when response is necessary, thereby freeing up the CPU to handle other tasks.
Armed with byte-erasable flash technology for enhanced flexibility and performance, the LPC900 family is based on a high-performance processor architecture that executes instructions in 167 ns at 12 MHz (600 percent improvement over the traditional 80C51). The LPC900 features a real-time clock and three other 16-bit counter/times. The family also features serial communication channels such as a 400 kHz byte-wide I2C-bus, enhanced UART and SPI. The flexible power management features also help extend the battery life of handheld applications.
Eying such household electric appliance markets as refrigerators, washers, dryers and air-conditioners that now demand lower noise, vibration and power consumption through intelligent motor control, NEC Electronics America Inc. has launched its uPD78F0714 and V850ES/IK1 series of single-chip MCUs for inverter-control applications. Both the uPD78F0714 and V850ES/IK1 series come with a number of safety features necessary for motor-control applications. These include an emergency shutdown pin for the inverter timer outputs to protect the motor and inverter, and a power on clear (POC) and a low voltage interrupt (LVI) for a controlled system shutdown and recovery in the event of power failure.
The uPD78F0714 and V850ES/IK1 series are also suitable for a variety of other applications including industrial inverter-control systems such as uninterruptible power supplies (UPS), AC servos and general-purpose inverters, as well as electric bicycles with inverter modules, which serve as power generators for variable voltage.
The uPD78F0714 operates at 20 MHz and is the latest addition to the company's 78K0 family of 8-bit MCUs. The device packs 32 kilobytes embedded flash memory and 1Kbyes of RAM, along with dedicated 3-phase inverter functions. There is also an on-chip debug function that allows developers to design and debug products in circuit via a serial connection.
Earlier this year, STMicroelectronics (Lexington, Mass.) extended its ST7 family of 8-bit microcontrollers with the launch of its ST7MC family, specifically intended for the control of three-phase induction and permanent magnet brushless motors (including compressors). Packed into the MCU chip is ST's motor control peripheral, the MTC, which consists mainly of a three-phase pulse width modulator multiplexed on six high-sink outputs, with a Back EMF (BEMF) zero-crossing detector and co-processor unit for the sensorless control of permanent magnet Brushless Direct Current (BLDC) motors.
The MTC's input pins can also be configured for Hall, tachometer or encoder sensing. In addition, comprehensive filters and settings allow the control of any star or delta wound motor, from 12V to 240V, in various control topologies (six-step/Sine wave, Current/Voltage, PAM/PWM).
Air conditioners, refrigerators, washing machines, automotive fans and pumps, HVAC (Heating, Ventilation and Air Conditioning) fans and actuators, office automation, electric vehicles and low-end to medium industrial drives are the major targets for this new microcontroller family. With increasing pressure to minimize power consumption, the ST7MC will allow improvements in the energy efficiency of pumps, fans and compressors in these and other industrial, appliance and automotive applications. Four different power-saving modes minimize consumption in the device itself, according to STMicroelectronics.
Also, packing lots of interesting peripheral functions into a new 8-bit MCU is Zilog, Inc. (San Jose, Calif.) Touting a high level of integration with low overall system cost, the company's Z8 Encore! XP integrates a full range temperature sensor and a trans-impedance amplifier, which have their outputs processed by a sigma-delta A/D converter. With the sigma-delta approach, the full 10-bit accuracy of the converter is realized, even with the microcontroller running full speed, and with no external signal filtering components required. ZiLOG director of product marketing Michael Gershowitz, said.
For details of the chip, see diagram below,
The Z8 Encore! XP is a scalable family of MCUs covering program memory sizes from 1KB to 64KB. It uses ZiLOG's register-to-register based architecture and features an 8-channel, 10-bit Sigma Delta A/D converter. Unlike A/Ds that are based on SAR implementations, the Encore A/D doesn't require halting the processor to get the full 10-bit accuracy.The MCU provides further system cost savings by fully integrating the anti-aliasing filters internally, saving on external component count as well as delivering more accurate bandpass performance. With additional integrated features such as an on-chip- precision internal oscillator, non-volatile data storage memory, and large working memory, the MCU performs favorably versus competing solutions.
The MCU comes in 20 or 28-pin SOIC, SSOP and PDIP packages. The units are priced at 89 cents for a 1KB device in 20-pin SOIC and $1.44 for a 4KB device in 28-pin SOIC, each in 10K quantities.