Driver circuit for an addressable array of optical emitters
In some implementations, a controller may cause a first switch of a driver circuit to transition from an open state to a closed state to charge an inductive element of the driver circuit. The controller may cause the first switch to transition from the closed state to the open state to discharge the inductive element. The controller may cause a second switch of the driver circuit to transition from an open state to a closed state to select a capacitive element to be charged by discharging the inductive element. The controller may cause a third switch of the driver circuit to transition from an open state to a closed state to discharge the selected capacitive element to provide an electrical pulse to an optical emitter, of an array of optical emitters of the driver circuit, that is connected to the selected capacitive element.
1 . A driver circuit, comprising:
an array of vertical cavity surface emitting lasers (VCSELs);
a plurality of capacitive elements connected to respective VCSELs of the array of VCSELs;
an inductive element;
a first switch having an open state and a closed state,
wherein the first switch in the closed state is to cause a charging of the inductive element, and
wherein the first switch transitioning from the closed state to the open state is to cause a discharging of the inductive element;
a plurality of second switches, each having an open state and a closed state, between the inductive element and the plurality of capacitive elements,
wherein the plurality of second switches are connected to respective capacitive elements of the plurality of capacitive elements, and
wherein a second switch, of the plurality of second switches, in the closed state is to select a capacitive element, of the plurality of capacitive elements, that is to be charged by the discharging of the inductive element; and
a third switch, having an open state and a closed state, to control current to the array of VCSELs,
wherein the third switch in the closed state is to cause a discharging of the selected capacitive element to provide an electrical pulse to a VCSEL, of the array of VCSELs, that is connected to the selected capacitive element, and
wherein the first switch is configured to be in the closed state for a duration that is based on an inductance of a circuit path between the inductive element and the VCSEL.
2 . The driver circuit of claim 1 , further comprising:
a plurality of blocking diodes between the plurality of second switches and the plurality of capacitive elements.
3 . The driver circuit of claim 1 ,
wherein the array of VCSELs is arranged in a plurality of rows, and
wherein the plurality of capacitive elements are configured to be respective voltage sources for the plurality of rows.
4 . The driver circuit of claim 1 ,
wherein the duration is variable based on a capacitance value of a particular capacitive element, of the plurality of capacitive elements, that is to be charged by the discharging of the inductive element.
5 . The driver circuit of claim 1 ,
wherein the duration is based on a length of the circuit path, and
wherein the circuit path includes the selected capacitive element and the third switch.
6 . The driver circuit of claim 1 ,
wherein the first switch is configured to be controlled by a first signal, and
wherein the second switch is configured to be controlled by a second signal that is an inverse of the first signal.
7 . The driver circuit of claim 1 ,
wherein the inductive element is configured to boost an input voltage of the driver circuit.
8 . An optical source, comprising:
an array of optical emitters;
a plurality of capacitive elements connected to respective optical emitters of the array of optical emitters;
an inductive element;
a first switch having an open state and a closed state,
wherein the first switch in the closed state is to cause a charging of the inductive element, and
wherein the first switch transitioning from the closed state to the open state is to cause a discharging of the inductive element;
a plurality of second switches, each having an open state and a closed state, between the inductive element and the plurality of capacitive elements,
wherein the plurality of second switches are connected to respective capacitive elements of the plurality of capacitive elements, and
wherein a second switch, of the plurality of second switches, in the closed state is to select a capacitive element, of the plurality of capacitive elements, that is to be charged by the discharging of the inductive element; and
a third switch, having an open state and a closed state, to control current to the array of optical emitters,
wherein the third switch in the closed state is to cause a discharging of the selected capacitive element to provide an electrical pulse to an optical emitter, of the array of optical emitters, that is connected to the selected capacitive element, and
wherein the first switch is configured to be in the closed state for a duration that is based on an inductance of a circuit path between the inductive element and the optical emitter.
9 . The optical source of claim 8 ,
wherein the duration is variable based on a capacitance value of a particular capacitive element, of the plurality of capacitive elements, that is to be charged by the discharging of the inductive element.
10 . The optical source of claim 8 ,
wherein the duration is based on a length of the circuit path, and
wherein the circuit path includes the selected capacitive element and the third switch.
11 . The optical source of claim 8 ,
wherein the first switch is configured to be controlled by a first signal, and
wherein the second switch is configured to be controlled by a second signal that is an inverse of the first signal.
12 . The optical source of claim 8 ,
wherein the array of optical emitters is one dimensional.
13 . The optical source of claim 8 ,
wherein the array of optical emitters is an array of vertical cavity surface emitting lasers (VCSELs).
14 . The optical source of claim 8 ,
wherein the optical source is configured for use in a light detection and ranging (LIDAR) system.
15 . A method, comprising:
causing, by a controller, a first switch of a driver circuit to transition from an open state to a closed state to charge an inductive element of the driver circuit;
causing, by the controller, the first switch to transition from the closed state to the open state to discharge the inductive element,
wherein the driver circuit is configured to cause the inductive element to discharge to any one of a plurality of capacitive elements of the driver circuit;
causing, by the controller, a second switch of the driver circuit to transition from an open state to a closed state to select a capacitive element, of the plurality of capacitive elements, to be charged by discharging the inductive element; and
causing, by the controller, a third switch of the driver circuit to transition from an open state to a closed state to discharge the selected capacitive element to provide an electrical pulse to an optical emitter, of an array of optical emitters of the driver circuit, that is connected to the selected capacitive element,
wherein the first switch is configured to be in the closed state for a duration that is based on an inductance of a circuit path between the inductive element and the optical emitter.
16 . The method of claim 15 ,
wherein the first switch is caused to transition from the closed state to the open state concurrently with causing the second switch to transition from the open state to the closed state.
17 . The method of claim 15 ,
wherein the duration is based on a capacitance value of the selected capacitive element.
18 . The method of claim 15 ,
wherein the duration is based on a length of the circuit path, and
wherein the circuit path includes the selected capacitive element and the third switch.
19 . The method of claim 15 ,
wherein a state of the first switch is controlled using a first signal, and
wherein a state of the second switch is controlled using a second signal that is an inverse of the first signal.
20 . The method of claim 15 ,
wherein the array of optical emitters is an array of vertical cavity surface emitting lasers (VCSELs).