EL SEGUNDO, CA. December 2000 - International Rectifier (NYSE:IRF - news) has introduced the IR2170, a 600V over-current sensing IC for AC or brushless DC motor drive applications up to 230VAC input. The IR2170 senses motor current directly through an external sense resistor and reports an error if the current exceeds a preset threshold in both the positive and negative polarities.

IR's patented high voltage IC technology enables smaller circuit size and reduces component count and cost. Typical applications include light industrial AC and brushless DC motor drives, and appliance applications such as washing machines and air conditioners.

The IR2170 includes a 1.5 microsecond over-current shutdown that works with a wired-OR connection directly to the microcontroller or DSP. Motor current in both positive and negative directions are sensed by the IR2170 so that both IGBT and diode over-current conditions are reported. Conventional linear current-sensing optical- or Hall effect-based systems have typical shutdown times of three to four microseconds. Motor drive circuits using opto- or Hall-effect sensors require two external comparators and a level-shift operational amplifier to achieve the same function.

The IR2170 requires one milliamp (1mA) quiescent current and an input supply voltage range of 7 to 20V. Sharing the bootstrap supplies with the HVIC gate driver eliminates the need for separate, isolated supplies. Internal filtering and high speed transient response time eliminates false alarms often generated by competing over current protection solutions.

According to David Tam, Vice President for power integrated circuit products at IR, ``Motor drives using the IR2170 have smaller, simpler circuits with up to 75% smaller footprint, less than 1.5 microseconds response time, and significantly reduced costs for over-current protection circuits compared to opto- or Hall-effect-based solutions.''

The new over-current protection IC comes in either SO-8 or 8-pin DIP. The IR2170 is the latest addition to the IR217x family of integrated, high voltage current-sensing and protection ICs. Other devices in the family include the IR2171 which sends a linear current sense output signal in PWM format and the IR2172 which combines the functions of the IR2170 and IR2171.

Pricing and Additional Information

The IR2170 is targeted for high volume light industrial and appliance applications. Pricing begins at US $0.99 each in 100,000-unit quantities.