Green and faster – Infineon paves the way for new motor driven applications
(Technology News, 25 Apr 2008 )
Infineon Technologies has announced new members to its NovalithIC family of highly integrated driver ICs for motor drive applications, adding RoHs compliant and faster switching versions. The NovalithIC combines three integrated circuits in one small package, using latest chip-by-chip as well as chip-on-chip technologies. This device cuts by half the space needed on a printed circuit board for power electronics driving motor applications with industry leading currents of up to 70 Ampere. This makes the NovalithIC ideal for use in motor drive applications like automotive heating, ventilation air-conditioning systems (HVAC), seat belt systems and fuel pumps as well as in industrial applications such as battery driven power drillers and grinding machines. With the latest version, the BTN7971B, Infineon achieved to double the switching speed of the previous devices, further reducing the switching losses by 50 percent.
The family of NovalithIC presents a fully integrated high current half bridge for motor drive applications. A NovalithIC chip contains one p-channel highside MOSFET and one n-channel lowside MOSFET with an integrated driver IC in one package. As the on state resistance is typically just 16 mOhm and the quiescent current just 7 µA the device has a very energy efficient footprint marking another benefit of this device. The architecture eliminates the need for a charge pump thus minimizing EMI (Electro Magnetic Interference).
As a motor driver IC with logic level inputs, diagnosis with current sense, over- and undervoltage and many other features have been integrated into the NovalithIC, the interfacing with a microcontroller do not require additional efforts. Since the NovalithIC supports applications up to 70A new applications like seatbelt pretensioner can be realised for the first time with such a highly integrated device.
Today a mid-range car uses up to 50 small electrical motors. They are used to change the position of seats, to lift windows and to operate the sun roof. In the premium car segment this number already grows up to 70 motors. But not all motor drive applications make use of PWM (Pulse Width Modulation) technology, reducing the energy required for the desired features significantly.
Air-conditioning fans in many vehicles are already fitted as standard with a PWM control unit. However a substantial proportion of fans on the market still use a linearly driven MOSFET as an external resistance between fan and motor, turning between 80 W and 130 W of power into waste heat. For example a mean reduction in heat loss of around 80 W would equal a saving of 1.9 g CO2/km or 0.08 litre gasoline per 100km. The additional expense of installing a PWM fan controlled by a NovalithIC would pay for itself in just 0.5 years or after just 8,000 kilometers (source: ATZelektronik 01I2008 Volume 3, www.infineon.com/co2-reduction-in-cars).
According to independent market analysts this will lead to an increased demand for NovalithIC and its kind. The motor drive market is expected to grow stronger than the automotive market in general and will reach a CAGR (2008-2013) over 10 percent.
