One popular applications with Smart DACs is LED biasing. The top right corner of the board is dedicated to a LED biasing module. The area supports both high-side and low-side LED biasing. A banana jack (J1) supplies power for this subsection of the board. The banana jack can be isolated by removing resistors R1 through R4.

LED biasing requires an external FET to set set up current throught the LED. The board provides an option between high side and low side configuration. Populate FET, LED and resistor on the board. Headers (J3, J4, J5 J6) provide connection to additional signals. Pin LED_PWR for the system. It is equal to the banana jack input (J1) if corresponding resistor is populated. SINK_FB pin provides feedback connection in case current sink configuration is used. It is not connected to anything so connection needs to be established to the corresponsing feedback pin of the DAC that is being used. LED_BIAS pin is the gate voltage for the FET. It must be connected to the corresponding output DAC channel. SRC_FB pin is the feedback connection for current source configuration. It is not connected to anything so connection needs to be established to the corresponsing feedback pin of the DAC that is being used.

Please refer to the circuit diagram printed directly on the board for connection guidance.