The power tools market is seeing a lot of exciting changes. Corded tools are rapidly being replaced by cordless ones with powerful battery packs that require fast charging. Many manufacturers have begun to explore gallium nitride (GaN) options to create chargers with higher power levels, increased efficiency and compact form factors.
PowiGaN-based switcher IC and power factor correction (PFC) IC products from Power Integrations (PI) can easily replace traditional silicon devices in charger designs, allowing power tool makers to make a smooth
Source: PI transition to GaN.
A new reference design (DER-930) from PI details how to create a 180 W power tool charger utilizing two highly integrated PI devices featuring 750 V-rated PowiGaN switches:
- InnoSwitch4-CZ flyback switcher IC (paired with ClampZero active clamp IC) realizes zero voltage switching and eliminates the need for bulky metal heatsinks, as well as half of the number of passive components, metal-oxide-semiconductor field-effect transistors (MOSFETs) and diodes that make safety-compliant PCM layout difficult. Switching at up to 140 kHz also minimizes transformer size.
- HiperPFS-5 PFC IC features quasi-resonant DCM control, ensuring low switching losses, smaller inductor size than conventional CRM PFC, and permitting the use of low-cost boost diodes. The innovative new device offers high efficiency across the entire load range and a power factor over 0.98 at full load and 0.96 at 20% load.
This powerful combination of switches enables DER-930 to deliver 9 A fast charging while achieving 95% efficiency. The ultra-compact design requires only 48 components for the flyback stage and 37 for the PFC stage.
