LIN Bus Microcontroller drives 12V loads

Micronas announced its easyLIN product line of 8-bit microcontrollers for LIN bus applications. Today's cars and trucks have multiple LIN bus modules connecting smart sensors and controlling smart actuators used in power windows, wipers, and many other functions. The HVC 22xyA and HVC 24xyA simplify the design and reduce the cost of LIN bus modules by combining all logic functions, peripheral modules, interfaces and a LIN bus interface in a single device. The family devices integrate 5V and 2.5V regulators, true EEPROM, watchdogs and power-driver electronics. The included internal voltage regulators operate directly from an automobile's 12-volt supply and withstand load dumps of up to 40 volts, a requirement in vehicle applications. easyLIN also contains a switchable 5-volt supply output, which can be used to power external subsystems.

 Complementing the high-voltage-tolerant regulators, the family can directly drive up to eight 12-volt loads, such as lamps and relays. Relay driver protection is also embedded. The on-chip transistors resist moderate loads, and can drive external power transistors for large loads. These drivers include three fast-shutdown modules for power MOSFET transistor protection that respond virtually on the instant, without CPU involvement. Working with on-chip pulse-width modulators (PWM), easyLIN can also drive brushed and brushless DC motors. Combining all these features with a sophisticated 8051-type 8-bit CPU core and a full range of peripherals, the easyLIN family is typically the only component needed for a LIN bus slave application.

 The easyLIN is a complete digital subsystem: It has a full LIN 2.0 physical layer interface, a fast 10-bit queued ADC (analog-to-digital converter), three multithreshold comparators, an op-amp, and multiple interrupt inputs. It is available in Flash and ROM versions, both types include true EEPROM. Other integrated peripherals include two 8-bit and two 16-bit timers, an SPI interface, a 16-bit PWM and three enhanced 12-bit PWMs. In addition, the easyLIN contains its own supervisory circuit. An on-chip temperature sensor against an overheat condition, and a supply monitor resets the device if the power supply goes out of range, even momentarily. All easyLIN family devices operate from -40 to +125 °C, necessary in the harsh environment of automotive electronics. The family offers a range of power-saving modes, with current consumption as low as 20 µA while still preserving RAM data.

 Micronas supplies a number of development tools. For hardware development, application/evaluation boards and JTAG/Trace probes are available. For software development, a full range of tools from third-party vendors are offered. Micronas supplies an API (Application Programming Interface) with support for all peripherals. Fast-turn development is supported by contact-ROM technology for quick turns and a patch module for in-the-field changes of code or data in ROM. The device is offered in a PSOIC28 package. Pricing varies with the exact model, but ranges from 1.60 to 2.20 Euro for low quantities.