GaN Talk a blog dedicated to crushing silicon

Pulsing 1550 nm Lasers for Lidar

Pulsing 1550 nm Lasers for Lidar
Apr 20 2021

Pulsed lidar systems typically use either 905 nm or 1550 nm lasers for optical emission.  Above 1400 nm, various elements of the eye absorb the light, impeding it from reaching and damaging the retina.  As laser power is increased, not all of it is absorbed, and at some point, retinal damage may occur.  Since 905 nm light does not get absorbed, it does reach the retina, so care must be used to limit the energy density to prevent damage.

If the decision is to use 1550 nm light, efficiency differences in the semiconductor laser make it necessary to use higher current for the same optical power emitted compared with 905 nm light.  Additionally, the same characteristics that allow the light to be absorbed by the eye before getting to the retina cause it to be absorbed by the atmosphere.  This phenomenon is amplified as humidity increases to fog, rain, or snow.  The drive power required for a 1550 nm laser may be up to 10 times higher than for a 905 nm laser based system.  Fortunately, there is a solution to deliver the power necessary to drive 1550 nm lasers while maintaining the edge speed and pulse required for high resolution in pulsed lidar applications.

GaN + Digital Control + High-Performance Magnetics
Designing an Ultra-thin, Highly Efficient (>97%), Multilevel DC-to-DC Converter

GaN + Digital Control + High-Performance Magnetics<br>Designing an Ultra-thin, Highly Efficient (>97%), Multilevel DC-to-DC Converter
Apr 07 2021

GaN-based solutions coupled with digital control and high-performance magnetics can increase efficiency, shrink the size, and reduce system costs for high density computing applications like ultra-thin laptops and high-end gaming systems.

As computers, displays, smart phones and other consumer electronics systems have become thinner and more powerful over the past decade, there is increasing demand for addressing the challenge of thinner solutions while extracting more power out of limited space.

The multilevel converter is an exceptional candidate to shrink the size of the magnetic components and achieve high efficiency in a compact solution. Leveraging the advantages of eGaN® FETs, such as small size and low loss, further enhances the performance of a multilevel solution. This blog will evaluate the EPC9148, a 48 V to 20 V, 250 W three-level converter using eGaN FETs and digital control which achieves a peak total system efficiency of 97.8% and only 4.1 mm component height.

eToF™ Laser Driver ICs for Advanced Autonomy Lidar

eToF™ Laser Driver ICs for Advanced Autonomy Lidar
Mar 22 2021

Co-written by Steve Colino

Laser drivers for light distancing and ranging (lidar) are used in a pulsed-power mode. What are the basic requirements for these laser drivers?

A new family of integrated laser driver ICs meets all these requirements.  The first release, the EPC21601 laser driver IC, integrates a 40 V, 10 A FET with integrated gate driver and 3.3 V logic level input in a single chip for time-of-flight (ToF) lidar systems used in robotics, surveillance systems, drones, autonomous cars, and vacuum cleaners. This chip offers frequency capability up to 200 MHz in a low inductance, economical, 1 mm x 1.5 mm BGA package.

Why GaN for DC-DC Space Designs

Why GaN for DC-DC Space Designs
Mar 03 2021

Power electronics engineers are constantly working towards designs with higher efficiency and higher power density while maintaining high reliability and minimizing cost. Advances in design techniques and improved component technologies enable engineers to consistently achieve these goals. Power semiconductors are at the heart of these designs and their improvements are vital to better performance. In this EPC space blog, we will demonstrate how GaN power semiconductors allow for innovation in the harsh radiation environments of space applications.

GaN power semiconductors offer designers in the high reliability market a sudden and significant improvement in electrical performance over their silicon power MOSFET predecessors. Table 1 compares radiation hardened GaN and Si power semiconductor device characteristics important for circuit designers to increase efficiency and power density in their converter.

How GaN is Revolutionizing Motor Drive Applications

How GaN is Revolutionizing Motor Drive Applications
Feb 09 2021

Rethinking the Ordinary and Overcoming Mental Biases

Motor drive applications span several markets: industrial, appliance, and automotive. A commonality that occurs regardless of market is that when a new technology is proposed, it faces resistance to its adoption; after all, it is human nature to stick with what is known and resist change.

Reduce Audible Noise in Motor Drive Designs Using eGaN FETs and ICs

Reduce Audible Noise in Motor Drive Designs Using eGaN FETs and ICs
Jan 15 2021

Brushless DC (BLDC) motors are popular and finding increasing application in robotics, e-mobility, and drones. Such applications have special requirements such as lightweight, small size, low torque ripple, low audible noise, and extreme precision control.  To address these needs, the inverters powering the motors need to operate at higher frequency but require advanced techniques to reduce the resultant higher power loss. Enhancement-mode gallium nitride (eGaN ®) transistors and integrated circuits offer the ability to operate at much higher frequencies without incurring significant losses. 

How to Design a Bi-Directional 1/16th Brick 48 V-12 V Converter Using Monolithic GaN ePower™ Stage

How to Design a Bi-Directional 1/16th Brick 48 V-12 V Converter Using Monolithic GaN ePower™ Stage
Dec 15 2020

Brick DC-DC converters are widely used in data center, telecommunication and automotive applications, converting a nominal 48 V bus to (or from) a nominal 12 V bus. Advances in GaN integrated circuit (IC) technology have enabled the integration of the half bridge and gate drivers, resulting in a single chip solution that simplifies layout, minimizes area, and reduces cost.

This application note discusses the design of a digitally controlled bi-directional 1/16th brick converter using the integrated GaN power stage for 48 V-to-12 V application, with up to 300 W output power, and peak efficiency of 95%.

The standard dimension of the 1/16th brick converter is 33 x 22.9 mm (1.3 x 0.9 inch). The height limit for this design is set to 10 mm (0.4 inch).

How to Design a Highly Efficient, 2.5 kW, Universal Input Voltage Range, Power Factor Correction (PFC) 400 V Rectifier Using 200 V eGaN® FETs

How to Design a Highly Efficient, 2.5 kW, Universal Input Voltage Range, Power Factor Correction (PFC) 400 V Rectifier Using 200 V eGaN<sup>®</sup> FETs
Nov 03 2020

Acknowledgement - This application note and associated hardware was developed in collaboration with Semiconductor Power Electronics Center (SPEC) at University of Texas at Austin.

Motivation

The expansion of applications such as cloud computing, wearables, machine learning, autonomous driving, and IoT drive us towards an even more data-intensive world, increasing demands on data centers and power consumption [1, 2]. The importance of efficiency, power density, and cost of the AC to DC switching power supply is driving innovative solutions that eGaN FETs can solve to yield ultra-high efficiency power factor correction (PFC) front-end rectifier solutions that are the focus of this how-to-application note.

New 100 V eGaN Devices Increase Benchmark Performance Over the Aging Silicon Power MOSFET

New 100 V eGaN Devices Increase Benchmark Performance Over the Aging Silicon Power MOSFET
Sep 22 2020

Efficient Power Conversion (EPC) is increasing the performance distance between the aging silicon power MOSFET and eGaN transistors with 100 V ratings.  The new fifth-generation “plus” devices have about 20% lower RDS(on) and increased DC ratings compared with the prior fifth-generation products.  This performance boost comes from the addition of a thick metal layer and a conversion from solder balls to solder bars.

New 200 V eGaN Devices Double the Performance Edge Over the Aging Silicon Power MOSFET.

New 200 V eGaN Devices Double the Performance Edge Over the Aging Silicon Power MOSFET.
Aug 21 2020

Efficient Power Conversion (EPC) is doubling the performance distance between the aging silicon power MOSFET and eGaN® transistors with 200 V ratings.  The new fifth-generation devices are about half the size of the prior generation.  This performance boost comes from two main design differences, as shown in figure 1.  On the left is a cross-section of the fourth generation 200 V enhancement-mode GaN-on-Si process.  The cross-section on the right is the fifth-generation structure with reduced distance between gate and source electrodes and an added thick metal layer. These improvements, plus many others not shown, have doubled the performance of the new-generation FETs.