Infineon Serves Up GaN 40 V Switches Aimed at Portable Power Designs

Just lately, Infineon Technologies announced the growth of its CoolGaN BDS 40 V G3 bidirectional swap (BDS) household with two new units, the IGK048B041S and IGK120B041S. Designed to switch two back-to-back silicon MOSFETs with a single GaN machine, the brand new BDS options are mentioned to cut back PCB footprint by as much as 82 p.c and lower part depend in half relative to equal discrete MOSFET implementations.

Infineon’s GoolGaN BDS 40 V G3 MOSFET

IGK048B041S and IGK120B041S

In response to Infineon, their two new 40 V switching devices are supposed to provide a smaller-area design choice for bidirectional functions. Fairly than bidirectional implementations based mostly on two discrete, back-to-back silicon MOSFETs, the BDS household options combine two GaN units in a drain-to-drain configuration. To this finish, Infineon designed each units to simply accept a typical 5 V gate-drive sign, which means engineers can reuse their current gate-drive circuits with out altering the {hardware}.

Protected working space for the IGK048B041S

Inside the household, the IGK048B041S is available in a WLCSP chip-scale bundle measuring 2.1 x 2.1 mm². At a gate-drain voltage of 5 V and drain present of 5 A, the machine posts an RDD(on) of 4.2 mΩ and handles as much as 53 A of steady drain present with pulsed present assist as much as 120 A.

For designers looking for the smallest transportable type elements, the IGK120B041S extends the advantages of its member of the family right into a 1.7 x 1.2 mm² bundle at 9 mΩ RDD(on). This smaller machine comes with barely lesser energy specs, together with steady and pulsed drain currents of 30 and 59 A, respectively. Extra info is on the market within the knowledge sheets for the IGK048B041S and IGK120B041S.

Bidirectional Blocking and GaN Leakage Benefits

Whereas silicon MOSFETs are perfect for many energy functions, they significantly wrestle in functions that require bidirectional switching. Specifically, each silicon MOSFET incorporates a parasitic physique diode that’s an inherent characteristic of the machine’s p-n junction. This diode conducts small quantities of present within the reverse route throughout restoration, which might create undesirable conduction fault paths.

To unravel this problem, engineers working across the physique diode usually stack two MOSFETs source-to-source in a back-to-back configuration, counting on the opposing physique diodes to dam in every route alternately. That method works, nevertheless it doubles the part depend and roughly doubles the board space consumed. The sequence connection additionally locations the on-resistance of two units within the conduction path.

Silicon MOSFETs carried out as bidirectional switches

GaN transistors eliminate the body diode problem at the material level. Enhancement-mode GaN units are lateral buildings constructed on a two-dimensional electron gasoline (2DEG) channel, they usually carry no parasitic p-n junction between drain and supply. When the gate is held under threshold, a GaN swap blocks present in each instructions with out further exterior parts.

This true bidirectional blocking functionality permits engineers to switch the two-MOSFET stack with a single machine in a drain-to-drain configuration, slicing part depend and board space whereas sustaining blocking efficiency in each instructions.

GaN additionally delivers switching and leakage benefits that matter in transportable and fast-charging functions. Gate cost determines how a lot vitality the motive force should ship per cycle and the way rapidly the machine transitions between states, making it the principle switching determine of advantage in high-frequency designs.

GaN units submit considerably decrease gate cost than silicon MOSFETs at equal on-resistance, which interprets straight into quicker switching transitions and decrease switching losses per cycle. On leakage, GaN’s large bandgap suppresses thermally generated carriers much more successfully than silicon, yielding drain-source leakage currents orders of magnitude under what a comparably rated silicon MOSFET produces.

Availability and Household Protection

With the IGK048B041S and IGK120B041S becoming a member of the beforehand launched IGK080B041S, the CoolGaN BDS 40 V G3 household now presents three on-resistance choices from 4.2 to 9 mΩ. Each new units can be found now by way of Infineon’s approved distribution channels.

All photographs used courtesy of Infineon.