Methods and systems of driving arrays of diodes

A diode driver for driving an array of diodes, the diode driver comprising:

• a power supply terminal, and a ground terminal;
• a first and second inductor terminals;
• a plurality of driver terminals;
• a substrate of semiconductor material;
• a plurality of row switches defined on the substrate, the plurality of row switches defining a respective plurality of control inputs, each of the plurality of row switches coupled to the second inductor terminal, and the plurality of row switches coupled one each to the plurality of driver terminals;
• a high-side switch defined on the substrate, the high-side switch defines a first lead coupled to the power supply terminal, a second lead coupled to the first inductor terminal, and a control input;
• a low-side switch defined on the substrate, the low-side switch defines a first lead coupled to the first inductor terminal, a second lead coupled to the ground terminal, and a control input;
• a shorting switch defined on the substrate, the shorting switch defines a first lead coupled to the second inductor terminal, a second lead coupled to the ground terminal, and a control input;
• a controller defined on the substrate and coupled the plurality of control inputs, and coupled to the control inputs of the high-side switch, low-side switch, and the shorting switch, the controller configured to:
• close the high-side switch, close the shorting switch, and open the low-side switch to increase an inductor current through an inductor coupled across the first and second inductor terminals;
• close a first row switch of the plurality of row switches;
• open the high-side switch, close the low-side switch, and open the shorting switch to drive the inductor current to a first driver terminal of the plurality of driver terminals;
• and then
• close the shorting switch to recirculate the inductor current.

A lidar system comprising:

• an array of laser diodes defining a plurality of rows, laser diodes of each row configured to be driven simultaneously;
• an inductor defining a first lead and a second lead;
• a plurality of row switches defining a respective plurality of control inputs, each of the plurality of row switches coupled to the second lead of the inductor, and the plurality of row switches coupled one each to the plurality of rows of the array of laser diodes;
• a high-side switch defining a first lead coupled to a power supply, a second lead coupled to the first lead of the inductor, and a control input;
• a low-side switch defining a first lead coupled to the first lead of the inductor, a second lead coupled to a ground, and a control input;
• a shorting switch defining a first lead coupled to the second lead of the inductor, a second lead coupled to the ground, and a control input;
• a controller coupled the plurality of control inputs, and coupled to the control inputs of the high-side switch, low-side switch, and the shorting switch, the controller configured to:
• increase an inductor current through the inductor by command to close the high-side switch, close the shorting switch, and open the low-side switch;
• couple a first row of the plurality of rows to the second lead of the inductor by command to close a first row switch of the plurality of row switches;
• drive the inductor current to the first row by command to open the high-side switch, close the low-side switch, and open the shorting switch;
• and then
• recirculate the inductor current by command to close the shorting switch.