PWM controllers boast 1% accuracy

An International Rectifier product story

Edited by the Electronicstalk editorial team Oct 28, 2005

International Rectifier has introduced two 1%-accurate single-output synchronous buck PWM controllers with 4.5 to 16V input voltage capability.

International Rectifier has introduced two 1%-accurate single-output synchronous buck PWM controllers with 4.5 to 16V input voltage capability.

The new IR3637SPbF and IR3637ASPbF are compact and simple solutions for up to 15A DC/DC point-of-load applications such as double-datarate (DDR) memory, field programmable gate arrays (FPGAs), and video graphics processors.

Combined with International Rectifier's broad selection of power MOSFETs, these two controllers offer greater design flexibility and improved performance versus integrated solutions.

Lead-free and compliant with the Restriction of Hazardous Substances Directive (RoHS), these two PWM controllers feature a 0.8V, 1% accurate voltage reference.

In next generation systems, peripheral rails can require as little as 3% total voltage error tolerance to ensure data signal integrity.

The two new PWM ICs with 1% accuracy allow designers to meet this stringent requirement.

Both ICs include short-circuit protection, input under-voltage lockout, and an externally programmable soft-start function.

The devices are available in the standard SO-8 package.

Operating at 400kHz, the IR3637SPbF is suitable for output currents up to 15A for applications including desktop motherboard peripheral rails such as DDR memory and chip set power.

The IR3637ASPbF runs at 600kHz and provides optimum efficiency in applications requiring less than 7A such as FPGAs.

The 600kHz operating frequency reduces required inductor size when compared with lower frequency solutions and increases control loop bandwidth for improved transient response.

Both PWM controllers are suitable for general purpose DC/DC conversion in a variety of other switching power supply applications.

Also available is the IRDC3637 reference design, which demonstrates performance for a 5V input, 1.8V output, DC/DC convertor delivering 7A of output current, using the IR3637SPbF.