Power Integrations' HiperLCS-2 Chipset Boosts LLC Converter & Company Announces Quasi-Resonant PFC IC with 750 V GaN Switch
April 11, 2022
Power Integrations announced the energy-saving HiperLCS-2 chipset, a new IC family that is designed to simplify the design and manufacture of LLC resonant power converters. The company also announced the HiperPFS-5 family of power-factor-correction (PFC) ICs with an integrated 750 V PowiGaN gallium-nitride switch
The new HiperLCS dual-chip solution features an isolation device with a high-bandwidth LLC controller, synchronous rectification driver and FluxLink isolated control link, alongside a separate half-bridge power device utilizing Power Integrations’ 600 V FREDFETs with lossless current sensing and high- and low-side drivers. Both devices are housed in low-profile InSOP-24 packages. This highly integrated, energy-efficient architecture is designed to eliminate heatsinks and reduce component count by up to 40 percent compared to discrete designs.
Edward Ong, senior product marketing manager at Power Integrations said: "Resonant converters using separate controllers and discrete MOSFETs can be incredibly bulky and are notoriously difficult to manufacture due to their complexity and high component count. We have applied our advanced FREDFETs and magneto-inductive FluxLink technology to the LLC topology, yielding 98 percent efficiency and reducing component count by 40 percent, while eliminating bulky heatsinks and unreliable optocouplers. This enables designers to create compact adapters and open-frame power supplies for TVs, monitors with USB PD ports, all-in-one PCs, game consoles and battery chargers for power tools and e-bikes.”
Resonant converters are typically used wherever an application demands a level of efficiency unachievable with single-switch topologies such as flyback converters. The HiperLCS-2 chipset leverages Power Integrations’ high-speed FluxLink feedback mechanism to avoid the compromises normally associated with the LLC topology, permitting designers to implement designs with high performance, wide operating range, and low component count.
Power supply designs based on the new HiperLCS-2 can achieve no-load input power of less than 50 mW at 400 VDC input and provide a continuously regulated output, complying with stringent no-load and standby efficiency regulations. HiperLCS-2 devices operate at high efficiency across the load range with dissipation so low that direct heat transfer through the FR4 PCB is all that is required, eliminating heatsinks in adapter designs up to 220 W continuous output with up to 170 percent peak power capability. All HiperLCS-2 family members feature self-powered start-up and provide the start-up bias for a PFC stage using the company’s HiperPFS ICs. Secondary-side sensing provides less than one percent regulation accuracy across line and load range and across production variations. Per the company, the use of Power Integrations’ FluxLink technology for safety-isolated high-speed digital feedback control provides ideal transient response and long-term reliability compared to optocouplers.
With efficiency of up to 98.3 percent, the HiperPFS-5 family of power-factor-correction (PFC) ICs deliver up to 240 W without a heat sink and can achieve a power factor of better than 0.98. HiperPFS-5 ICs are ideal for high-power USB PD adapters, TVs, game consoles, all-in-one computers, and appliances.
Edward Ong, senior product marketing manager at Power Integrations said: “With OEMs and after-market suppliers racing to create the fastest, smallest, most versatile USB PD chargers for mobile devices, HiperPFS-5 ICs give engineers a critical advantage. We have combined our proprietary PowiGaN switch with a quasi-resonant, variable-frequency discontinuous mode boost PFC topology. By pairing HiperPFS-5 ICs with our new HiperLCS™2 chipset or our InnoSwitch™4-CZ active-clamp flyback ICs, designers can easily beat even the most aggressive efficiency regulations while cutting the bill of materials by half and achieving extremely attractive form factors for ultra-fast chargers.”
The capacitors and inductors used in power supplies generate a phase change between current and voltage, causing losses in the power lines and potentially disrupting other equipment connected to the AC mains. Many countries require power supplies over 75 W to adjust for this effect with so-called power factor correction, or PFC. While there are many PFC solutions available, HiperPFS-5 ICs with PowiGaN technology and a quasi-resonant (QR) control scheme represent the pinnacle of the art and science of off-line power quality enhancement.
HiperPFS-5’s QR discontinuous conduction mode (DCM) control technique adjusts the switching frequency across output load, input line voltage, and input line cycle. QR DCM control ensures low switching losses and permits the use of a low-cost boost diode. Per the company, the variable frequency engine allows the reduction of boost inductor size by more than 50 percent compared to conventional critical-conduction-mode (CRM) boost PFC circuits. Low switching and conduction losses—which are further reinforced by the PowiGaN switch—together with lossless current sensing, mean that HiperPFS-5 ICs offer high efficiency across the entire load range, with efficiency rising as high as 98.3 percent. HiperPFS-5 ICs provide a PF higher than 0.98 at full load. At light loads a power-factor-enhancement (PFE) feature compensates for input filter capacitance, maintaining a high PF of 0.96 even at 20 percent load. No-load power consumption is just 38 mW.
Other benefits accrue due to the robust 750 V PowiGaN switch. In many locations worldwide the mains power can be highly unstable, often leading to over-voltage failure of power supply components. HiperPFS-5 ICs maintain a high power factor up to 305 VAC and can operate continuously at up to 460 VAC during line swells. Additionally, HiperPFS-5 ICs incorporate Power Integrations' automatic X-capacitor discharge (CAPZero) function, including the required redundant pins to meet safety regulations, and high-voltage self-start-up—all in a low-profile, InSOP-T28F SMD power package. Exposed cooling pads featured in the package are at source potential, providing effective cooling and simplifying the EMI solution. Digital line-peak-voltage detection ensures robust performance, even in the presence of distorted input from uninterruptable power supplies or generators.
A reference design, DER-672, is available to download for designers who want to evaluate HiperLCS-2 ICs. Pricing for the HiperLCS-2 starts at $3.20 per chipset in 10,000 unit quantities. The reference design is also available for designers wishing to evaluate the HiperPFS-5 quasi-resonant PFC controller ICs. Devices are priced at $2.34 in 10,000-unit quantities.
For more information, visit: power.com