The LMG1020 device is a single, low-side driver designed for driving GaN FETs and logic-level MOSFETs in high-frequency applications including LiDAR, time-of-flight, facial recognition, and any power converters involving low side drivers. The LMG1020EVM-006 is designed to evaluate the LMG1020. This EVM consists of one Gallium Nitride (GaN) enhancement mode FET driven by one LMG1020 and the drain of the GaN FET is connected to an unpopulated resistive load representing a typical laser diode load for LiDAR (Light Detection And Ranging) applications.

This User's Guide shows a circuit and the list of materials describing how to power the board up and how to configure the board. The EVM is designed to accelerate the evaluation of the LMG1020.

This EVM is not intended to be used as a standalone product but is intended to evaluate the switching performance of LMG1020.

This User's Guide describes correct operation and measurement of the EVM, as well as the EVM construction and typical performance.

The LMG1020EVM-006 is a small, easy-to-use power stage that comes with a place to populate a resistive load, representing a typical Lidar laser diode load, as well as a place to populate a laser diode. Section 6 explains the procedure to set up the board out-of-the-box and accommodate the resistive load. The unpopulated resistive load will help achieve the applications required pulses before populating and powering the laser diode. The EVM takes a short-pulse input that can either be buffered (and shortened), or passed directly to the power stage.

The input pulse signal is used to pulse the current through the load (not populated out-of-the-box), to achieve 1-ns to 2-ns wide current pulses, which are the state-of-the-art target for LiDAR systems.

The EVM features a LMG1020, driving a single EPC2019 FET referenced to ground and with the drain connected to the unpopulated resistive load.

The board comes with a place to populate a resistive load, as well as larger pads where a laser diode of choice can be mounted. The load (when populated) is split between two current loops to reduce the effective inductance.

Figure 2-1 LiDAR Power Stage with LMG1020

The power stage can deliver up to 40 A of current to the load (when populated) at duty cycles ~0.1% and frequencies up to 2MHz. It includes adequate thermal management (case temperature should be monitored and adequate airflow should be ensured).