The ATA6843 and ATA6844 devices from Atmel Corporation are highly-integrated gate driver ICs designed for 3-phase brushless DC (BLDC) motor control applications, including turbo chargers, waste gates, EGR, pumps, fans, power window, power doors and power seats. They feature six-output stages for direct motor control when combined with an Atmel AVR microcontroller (MCU), and an on-chip Atmel automotive LIN transceiver IP for in-car communication.
The company states the new driver ICs are the only products in the industry to incorporate all the essential functional blocks to supply and monitor a microcontroller in BLDC motor control applications. This feature enables a smaller footprint for applications with limited space and increases overall system safety.
With most automotive BLDC motor applications located in hot under-the-hood environments, the ability to withstand extremely hot temperatures is a device requirement. The new Atmel ATA6844 is a high-temperature version to operate at chip temperatures of up to 200°C. The device is manufactured in Atmel's own state-of-the-art BCD-on-SOI technology SMART-I.S. for extreme temperatures, and enables direct attachment of the ECU to hot actuators for short wiring and optimized construction.
Atmel automotive-qualified AVR microcontrollers are ideally suited to support the new system basis gate driver ICs in various BLDC motors with Hall sensors as well as sensorless BLDC motors with back-electromagnetic force (BEMF) sensing. With the devices' six input stages, the MCU individually controls each of the six output stages. The MCU also defines the adjustable overcurrent detection threshold of the ATA6843/44 to enable a current monitoring tailored to the various types of power MOSFETs used in the application.
The ATA6843 and ATA6844 contain comprehensive protection and diagnostic functions, such as monitoring of overtemperature, overvoltage, undervoltage, short-circuit conditions and charge-pump failures. All incidents are communicated via three-diagnostic outputs to the microcontroller to enable appropriate countermeasures. A coast function allows simultaneous disabling of all six output stages in case of emergency.
The on-board integrated watchdog independently monitors the MCU to increase the overall system safety, eliminating an additional external component. Dangerous short-circuit currents caused by faulty control signals are prevented from the pin-programmable timer stage that allows users to set a dead time for disabling unintended simultaneous activation of a high-side and a low-side power MOSFET within one branch.
With Atmel's LIN2.1-compliant transceiver IP integrated on chip, the new system-basis gate driver ICs are perfectly suited for in-car communication via the standard automotive network.
Availability and Pricing
Samples of the ATA6843 and ATA6844 are available now, both in QFN48 7 x 7mm packages. Pricing starts at USD $2.10 (ATA6843) and $2.40 (ATA6844) for quantities of 10,000. To simplify and speed-up bench tests, pre-programmed ATA6843/44 design kits for sensorless or Hall sensor type BLDC motors are also available.
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