EL SEGUNDO, CA. March 1997 - International Rectifier (IR) has developed a family of high-side and low-side MOSFET switches, called the POWIRSAFE series, that are designed with safety features to provide fail-safe performance in driving critical loads. These devices integrate control, protection, and output power MOSFET switch functions. This provides simple, load specific, and safe driving of DC motors, solenoids, valves, and lamp loads in automotive, industrial control, factory automation, and office machinery systems. Besides protecting the devices themselves, they also protect the micro-controllers to which they interface and the loads that they drive.

"Designing integrated high-side and low-side switches require understanding of the load characteristics and the electrical environment to fulfill the promises of fail-safe systems without the need to add extra components to fix unforeseen safety limitations," said David Tam, Vice President of the Power Integrated Circuits Group at International Rectifier. "The new generation of high-side and low-side switches from IR has been designed to provide extra levels of safety and reduced EMI as compared to competing devices on the market. They were tested to withstand combinations of common, as well as obscure, transient and broken load conditions."

The high-side switches, the IR62xx series, integrate the following major functional blocks into one chip: a high-side power MOSFET switch; a low noise charge pump gate drive; an inductive turn-off voltage clamp at 55V; a current limiter; over-current protection; over-temperature protection; and 5V logic level input interface and fault feedback. The operating supply voltage range is between 5-50V where full functionality and protection are guaranteed. Version with RDS(on) of 100Mor 200M are offered. Different control strategie3s are used in driving different types of loads. For example, in a lamp or motor load, the IR6216 or IR6226 will limit the load current to a constant value (set at 10A or 20A) until thermal shutdown at 165C is reached. This allows maximum in-rush current to heat up the lamp or start the motor. For solenoid load, the IR6210, IR6220, or IR6224 will go into a current limited (set at %A, 10A, or 20A) PWM mode when an over-current condition is detected. This allows minimum stress to the load, device, and wire harness.

The IR62xx series has superior competitive features that include:

• an ultra low noise charge pump circuit that eliminates extra external filtering. The IR devices are as much as 40db lower in current noise than competitive devices;
• a floating output stage that allows duty cycle control in all switching conditions that are required for motor and linear solenoid controls. Competitive devices lose control when output is in the re-circulation or re-generation stage;

• output under control of input even with a load to device ground offset up to 50V. Competitive devices either lose control or some may even self-destruct with ground offset due to the length of the harness, contact resistance, corrosion, etc.;
• survival with correct operating state during transient conditions in losing ground or supply while driving inductive loads. Competitive devices self-destruct or unwanted activation of loads may occur;
• an active-clamp inductive turn-off circuit that uses the energy absorbing mechanism of the power MOSFET in the active region which is superior to competitive devices that have limited inductive turn-off energy capabilities.

The low-side switch series include the IRSF3021 lamp or motor driver and the IRSF3031 solenoid driver. Common features for both products include: a low-side power MOSFET with Rds(on) rating of 200m; a 5V logic level gate drive; an internal slew rate control to reduce EMI; a low input current requirement of 100uA for directly interfacing with low current CMOS logic gate; a gate to drain active clamp of 55V for over-voltage protection; and a gate to source clamp of 10V for ESD protection. The IRSF3021 features a current limit of 5A and over-temperature protection with hysteretic auto re-start. The linear current limit is designed for lamp or motor load to allow maximum inrush current to heat up the lamp or start the motor. The IRSF3031 features different set and reset thresholds for interfacing with the PWM and enable signals through just a single input pin; a latched over-current shutdown of %A; and a latched over-temperature shutdown level of 165C. The latched input logic, latched over-current and over-temperature shutdowns are designed for PWM operation of linear solenoid load to minimize stress to the device and load. The input pin is isolated from the drain-source diode to allow diode conduction while driving motor or inductive load without unwanted reverse current going back to the micro-controller that interfaces to the device. The active clamp circuit allows fast demagnetization of the inductive load with high energy absorption capability.

The IR62xx series are packaged in a 5-pin TO-220, while the IRSF3021 and IRSF3031 are packaged in a 3-pin TO-220 or SOT-223. Samples are available now and volume production quantities are also available with a lead time of 8-12 weeks. Prices for the IR621x series are $1.50 for quantities of 1,000 and up, FOB USA. Prices for the IR622x are $1.75 for quantities of 1,000 and up, FOB USA. Prices of the IRSF3021 and IRSF3031 in TO-220 are $1.25 each and in SOT-223 are $1.00 each for quantities of 1,000 and up, FOB USA.

Part Number/ (Datasheet)	Topology	Current Limit	PWM Mode	RDS(on)	Application
IR6210	High-Side	5A	Yes	200m	Solenoid
IR6216	High-Side	10A	No	200m	Lamp or Motor
IR6220	High-Side	10A	Yes	100m	Solenoid
IR6224	High-Side	20A	Yes	100m	Solenoid
IR6226	High-Side	20A	No	100m	Lamp or Motor
IRSF3021	Low-Side	5A	No	200m	Lamp or Motor
IRSF3031	Low-Side	5A	Yes	200m	Solenoid

Contact the Technical Assistance Center or your local Sales Rep.