InnoSwitch4-CZ flyback switcher ICs add new dimension for mobile charging
Featuring a high frequency active clamp flyback controller to facilitate a new class of compact chargers suitable for phones, tablets, and laptops, the InnoSwitch4-CZ are high frequency, zero voltage switching (ZVS) flyback switcher ICs from Power Integrations. They also incorporate a 750V primary switch using Power Integrations’ PowiGaN technology.
“PowiGaN switches, in conjunction with our active clamp solution – ClampZero, enable a highly efficient design and an extremely compact form-factor,” said Balu Balakrishnan, CEO of Power Integrations.
The InnoSwitch4-CZ family incorporates 750V switch, primary and secondary controllers, ClampZero interface, synchronous rectification, and safety-rated feedback in a single, compact InSOP-24D package. A steady state switching frequency of up to 140kHz minimises transformer size, further increasing power density. The InnoSwitch4-CZ and ClampZero combination provides up to 95 per cent efficiency and maintains very high efficiency across variations in line voltage, system load and output voltage, compared with older active clamp flyback approaches, said Power Integrations. This is achieved with variable frequency asymmetrical control of the active clamp with intelligent zero-voltage switching, enabling both discontinuous and continuous conduction modes of operation. This enhances design flexibility and maximises efficiency across the entire operating envelope. The InnoSwitch4-CZ flyback switcher ICs enable “exceptional CV/CC accuracy, independent of external components”, says Power Integration. They also consume less than 30mW no-load including line-sensing safety and protection features.
Typical application examples for the InnoSwitch4-CZ ICs are compact USB PD adapters, high-density flyback designs up to 110W and high-efficiency CV/CC power supplies. In these applications, the ICs provide variable output voltage and constant current profiles. Devices feature auto-restart or latching fault response for output over-voltage and under-voltage protection, multiple output under-voltage fault thresholds and latching or hysteretic primary over-temperature protection.
The chipsets have been used by Anker it is latest USB-C chargers. “The InnoSwitch4-CZ was a natural choice for Anker’s new Nano II series of USB-C chargers,” explained Anker’s Steve Yang. “Its outstanding levels of integration and efficiency are key to the Nano II series’ extremely compact design,” he continued.
Power Integrations specialises in semiconductor technologies for high-voltage power conversion. The company’s products are key building blocks in the clean-power ecosystem, enabling the generation of renewable energy as well as the efficient transmission and consumption of power in applications ranging from mW to MW.
