EL SEGUNDO, CA, February 2002. - International Rectifier, IR® (NYSE: IRF) today announced the IRU3038, a synchronous PWM controller integrated circuit (IC) for the termination voltage requirements of double data rate (DDR) memory arrays. DDR memory is a fast-growing replacement for standard SDRAM, and is found in notebooks, desktops, servers and workstations as well as game consoles such as the Microsoft® X-box^tm. For example, Intel recently announced that its popular 845 chipset used in desktops and notebook computers, now supports DDR memory.

The new IRU3038 simplifies design and cuts component count, enabling cost-effective power management for DDR memory for currents in the 3 to 10A range. The IRU3038 is offered in two packages, an economical narrow body SOIC-14 and a small size TSSOP-14 package

To assure high data rate performance, DDR memory requires the termination voltage (Vtt) to be one half the supply voltage (VDDQ) within 3%. The IRU3038 integrates an error amplifier into the PWM controller package to make implementation of the power management circuit for Vtt easy and is capable of a voltage tracking accuracy of less than 1.5%. The IRU3038 integrates a high-side and low-side driver, eliminating external drive circuitry. This makes it easy to scale the design to drive multiple banks of memory.

In a synchronous buck converter, the IRU3038 provides current levels of up to 10A using the IRF7457 and IRF7460 HEXFET® power MOSFETs. For current levels up to 3A, the IRF7313 dual MOSFET can be used. The complementary and cost effective IRU3037 PWM controller combined with the IRF7457 and IRF7460 HEXFET MOSFETs is used to power the VDDQ supply voltage.

Reza Amirani, Director of Applications for Low Voltage ICs at International Rectifier said, "With the addition of the IRU3038 IC to its IC product line, IR offers a complete and cost effective power management chipset for DDR memory. This chipset makes it easy for designers to implement a simple and scalable design."

Technical Highlights

The IRU3038 is capable of operating with a single 5V or 12V supply voltage. The IRU3038 can be programmed to operate between 200 and 400kHz using an external resistor, simplifying the optimization of the design and layout to obtain the highest efficiency. The use of a voltage mode control loop enables a simple, more cost-effective design. The new device features under-voltage lockout for both VCC and VC supplies, an externally programmable soft start function as well as an output under-voltage detection that latches off the device when an output short is detected.

The IRU3038 features a 1.25V 1% reference that allows it to be used as a general purpose controller for on-board DC-DC conversion in applications such as graphics cards, desktop motherboards, set top boxes, communication equipment and hard disk drives.

Pricing and Availability

Samples and production quantities are available immediately. Pricing begins at US $0.82 each for 10,000 piece quantities for the IRU3038CF in a SOIC-14 package.

High Resolution JPEGs are available in the Press Room.