With the introduction of the CS1501/CS1601, Cirrus Logic continues to expand its line of digital power factor correction (PFC) ICs and sharpen its focus on new digital energy control-related products. Much like the CS1500/CS1600, which were introduced in 2010, these new digital PFC devices compete head-to-head with legacy analog PFC controllers by offering superior performance and allowing for simpler and smaller system designs.

The CS1501 and CS1601 are digitally controlled, variable frequency discontinuous conduction mode (VF-DCM), active power factor correction ICs intended for use in switch-mode power supplies. The CS1501 is designed to address power supplies rated up to 300 watts. while the CS1601 targets lighting applications, such as LED and fluorescent electronic lighting ballasts.

Featuring Cirrus Logic’s EXL Core™ architecture, with its 70 patented and patent-pending digital algorithm technologies in power management and energy control, the CS1501 and CS1601 provide an inherent advantage over legacy analog products by intelligently solving increasingly complex system level challenges that face power supply designers today. Through its patent-pending digital noise shaping technology, both the CS1501and CS1601 offer best-in-class THD, power factor and efficiency across all load conditions, while also reducing the size and number of required external components. The CS1501/CS1601 also offer an industry standard pinout to ensure an easy upgrade path from legacy analog solutions.

The unique digital architecture of the digital PFC controllers enables a reduction in the boost inductor value (LB), the size of the EMI filter stage and many external passive components. A variable on-time/ variable frequency algorithm is used to achieve close to unity power factor and spreading the EMI frequency spectrum, thus reducing the conducted EMI filtering requirements. The feedback loop is closed through an integrated compensation network within the IC, eliminating the need for additional external components. Protection features (such as overvoltage, overcurrent, overpower, open and short circuit protection, overtemperature, and brownout) help protect the device during abnormal transient conditions.