Analog Devices Inc. EVAL-LT8374-AZ LED Driver Evaluation Board

Small ceramic input and output capacitors are used to save space and cost. This evaluation board is designed with high-frequency capacitors close to the IC’s V_IN pins to form a compact switching hot loop for outstanding EMI performance. Ferrite bead filters placed at the input and output help further reduce switching emissions. The EMI filters at the input and output can be removed for great efficiency. Please follow the recommended layout and the four-layer PCB thickness of EVAL-LT8374-AZ for optimal performance.

The LT8374 features overvoltage protection (OVP) which uses the IC’s constant voltage regulation loop to regulate the output to approximately 40V in the case of an OPENLED event. A single resistor connecting VOUT to FB provides this regulation setpoint. LED current and output overvoltage protection (OVP) can be adjusted with simple modifications to EVAL-LT8374-AZ.

The LT8374 also features optional internal compensation options for reduced component-count designs. The external compensation components must be removed to utilize the internal compensation options and the VC pin must be left floating. With external compensation components extracted, the CAP pin can be left floating or connected to GND to select between the two internal compensation options. EVAL-LT8374-AZ is configured with an optimized external compensation network by default and includes a jumper for choosing between the two internal and external compensation configurations.

The Analog Devices LT8374 datasheet describes the device, its operation, and application information. The datasheet must be read with the demo manual for the evaluation board EVAL-LT8374-AZ. The LT8374 is assembled in a 16-lead plastic QFN package with a thermally enhanced exposed ground pad. The proper board layout is essential for maximum performance.