IR® Introduces High-Voltage Buck Control ICs for Constant LED Current Regulation
International Rectifier (IR)® introduced a high-voltage, high-frequency buck regulator control IC for ac-dc offline, non-isolated applications requiring multiple light-emitting diode (LED) circuits or requiring dc-dc color-mixing capabilities. Applications include indoor and outdoor signage as well as architectural, entertainment, design and decorative lighting.
Rated at 200 or 600V, the IRS254x series incorporates a continuous mode, time-delayed hysteretic buck regulator to control the average load current within a tolerance of 5%, using an accurate on-chip band gap voltage reference. An external high-side bootstrap circuit drives the buck switching element at high frequencies up to 500kHz. A low-side driver is also provided for synchronous rectifier designs.
"The IRS254x series of high-voltage buck control ICs, adapts and compensates to LED parameter variations to enable a design that is highly accurate and inherently stable," said Stephane Ernoux, Product Manager for IR's Lighting Products.
The new ICs deliver a micro-power startup of less than 500µA for extremely low losses at turn-on and a deadtime of 140ns for continuous current regulation. Other features include auto restart, non-latched shutdown and PWM dimmable capability, incorporated into a compact 8-pin DIP or 8-pin SOIC package, also available in tape and reel. These ICs utilize IR's advanced high-voltage IC process which incorporates latest-generation high-voltage level-shifting and termination technology to deliver improved electrical over-stress protection and high field reliability, in addition to other new features and enhancements.
Pricing (all in 10,000 unit quantities) begins at US $0.81 each for the IRS2540PbF and IRS2540SPbF and $0.83 for the IRS2540STRPbF. Pricing for the IRS2541PbF and IRS2541SPbF begins at $US0.89 and $0.91 for the IRS2541STRPbF. Production orders are available immediately. The devices are RoHS compliant.
