//php echo do_shortcode(‘[responsivevoice_button voice=”US English Male” buttontext=”Listen to Post”]’) ?>
Historically, energy designers needed to construct half-bridge circuits utilizing discrete transistors and a number of other exterior parts, similar to drivers, level-shifters, sensors, bootstraps, and peripherals. Navitas Semiconductor lately introduced the {industry}’s first GaNSense half-bridge energy ICs, accessible in a compact 6×8-mm surface-mount PQFN package deal.
These next-gen gallium nitride (GaN) half-bridge ICs ship 2-MHz switching frequency, with over 60% discount in parts and circuit measurement, in keeping with the corporate. That, in flip, reduces the system price and complexity in contrast with present discrete options that require a better variety of parts, are dearer, and ship decrease switching frequency, density, and effectivity.
As proven in Determine 1, the brand new units combine two GaN FETs with drivers, management, sensing, autonomous safety, and level-shift isolation, forming an entire power-stage constructing block for energy electronics.
GaN Units
“Our new GaNSense half-bridge energy ICs are an enormous step that can revolutionize energy electronics, since we combine every little thing in a single package deal, enabling megahertz switching frequencies in high-speed topologies”, mentioned Llew Vaughan-Edmunds, a director at Navitas Semiconductor.
For extra reliability and robustness, the built-in GaNSense expertise permits autonomous safety with loss-less present sensing for larger ranges of effectivity and vitality financial savings. Excessive integration ranges make it potential for quite a lot of AC-DC energy topologies, similar to LLC resonant, uneven half-bridge (AHB), and active-clamp flyback (ACF), to function at megahertz frequencies by eliminating circuit parasitics and delays. The totem-pole PFC and motor-drive purposes are likewise preferrred suits for the GaNSense half-bridge ICs.
The degrees {of electrical} energy required by the market are continuously rising. Typical energy rankings for quick chargers have elevated from 20-30 W to 65 W, and a brand new ultra-fast class launched with >100-W energy—even as much as 200 W delivering 0-100% charging of a 4,700 mAhr battery in lower than 10 minutes, Navitas mentioned. Equally, a knowledge heart’s goal effectivity goes from 80% to 90% or extra, whereas clients demand quicker charging of EVs, too.
The important thing options that the market calls for for present and future energy purposes are measurement, weight, effectivity, and velocity. Through the use of soft-switching topologies, similar to zero voltage switching (ZVS), the GaNSense half-bridge ICs decrease switching losses and improve effectivity, whereas additionally enabling quicker switching and a smaller footprint.
“We’re enabling the very best frequency, effectivity and probably the most compact design in soft-switching topologies and half-bridge platforms,” Vaughan-Edmunds mentioned. “Legacy silicon options have decrease frequency, decrease effectivity, and decrease energy density. With GaN, we are actually speaking about megahertz and plus switching frequency.”
Navitas mentioned its answer differs from opponents’ options in that it has an built-in gate drive (which eliminates parasitic inductance, turn-off, and false turn-on of eMode gate), safety of the delicate eMode gate node (which protects system from system noise and voltage spikes), and the high-feature GaNSense expertise.
This consists of superior options to simplify design, similar to commonplace and digital-logic inputs, high-side bootstrapping and level-shifting, and loss-less present sensing for the very best effectivity and biggest probability of first time-right, quickest time-to-market designs—in distinction to advanced, costly, and probably unstable discrete implementations. Shoot-through safety, over-current, over-temperature sensing and autonomous management, 2 kV ESD, and 200 V/ns slew-rate capabilities are all commonplace with this real IC.
A comparability between a discrete GaN half-bridge answer and an equal board designed utilizing GaNSense half-bridge IC is proven in Determine 2, as described by Vaughan-Edmunds.
“We will see how the GaNSense answer requires 61% fewer parts, has a considerably decrease footprint and offers greater integration. Furthermore, it doesn’t require exterior high-voltage bootstrap, high-voltage bypass diodes, and it doesn’t have uncovered gates. As proven in Determine 1, the 2 pads beneath of the 6×8 mm PQFN package deal have a bigger measurement for enhancing thermal administration,” Vaughan-Edmunds mentioned.
Among the many totally different safety measures supplied by GaNSense expertise, short-circuit safety is a key issue for motor drive purposes. As an alternative of getting 5 microseconds or 10 microseconds of delay because the brief circuit detection, the system switches itself off inside 30 nanoseconds—six instances quicker than discretes.
That is referred to as autonomous safety, because the GaNSense half-bridge energy IC doesn’t have to interrupt the microcontroller to inform it to modify it off; it switches off by itself. Footprint discount is a related function for mid-power motor drive purposes, as nicely.
The household of GaNSense half-bridge ICs begins with two components: the NV6247, rated at 650 V, 160 mΩ (twin), and the NV6245C, rated at 275 mΩ (twin). Each can be found in an industry-standard, low profile, low inductance, 6×8-mm PQFN package deal. Each ICs meet the demand coming from totally different energy purposes, together with cell quick and ultra-fast chargers, residence home equipment, and motor drive.
Instantly accessible in manufacturing with a 16-week lead time, the NV6247 is appropriate for cell and shopper purposes with energy ranges starting from 100 W to 140 W (like PFC and chargers), and for pumps and followers with energy as much as 400 W. The NV6245C is at the moment sampling to pick clients and can be broadly accessible in manufacturing to all clients by the top of this yr. The GaNSense half-bridge IC household will then increase, providing a variety of package deal types and energy ranges within the coming quarters.
Motor Management
GaNSense half-bridge ICs additionally allow inverter-motor integration. Three half-bridges are usually used to offer a three-phase topology in fashionable variable-speed drives for electrical motors, as utilized in family home equipment, HVAC, industrial equipment, EVs, and robotics. Most of as we speak’s motor-drives are low-frequency and hard-switched. GaN’s low switching capacitance and the absence of a reverse-recovery cost permit switching frequencies to be elevated whereas minimizing losses even in hard-switching purposes.
In line with Navitas, an influence loss comparability amongst IGBT, SJ MOSFET, and GaNFast IC in motor-drives reveals how GaN achieves a 78% discount in whole energy loss, whereas concurrently working 3× quicker than a legacy Si IGBT design. Through the use of GaN Energy ICs right into a 2-kW motor drive design, the inverter effectivity will increase 2.5% (from 96% to 98.5%), whereas whole losses cut back 50% (from 15 W to six.8 W).
“We’re additionally eliminating the heatsinks, and we’re going to place this into the motor shaft,” Vaughan-Edmunds mentioned. “For the shoppers who need the motor-integrated inverter, it is a excellent answer. We really feel we’ve got the very best integration stage.”
