Multi-junction solid state transducer devices for direct AC power and associated systems and methods
Multi-junction solid-state transducer (SST) devices and associated systems and methods are disclosed herein. In several embodiments, for example, an SST system can include a first multi-junction SST chain having a first drive voltage, a first P-contact, and a first N-contact, and a second multi-junction SST chain having a second drive voltage, a second P-contact, and a second N-contact. The first and second multi-junction SST chains can be configured to be activated independently of each other. The SST system can further include a driver operably coupled to the first and second P- and N-contacts. The driver can be configured to activate the first multi-junction SST chain when voltage input is at least equal to the first drive voltage. When absolute voltage increases a predetermined voltage level, the driver can be configured to activate the second multi-junction SST chain or the first and second multi-junction SST chains.
1. A solid-state transducer (SST) system, comprising:
a first multi-junction SST chain having a first drive voltage, a first P-contact, and a first N-contact; and
a second multi-junction SST chain having a second drive voltage, a second P-contact, and a second N-contact, wherein the first and second multi-junction SST chains are configured to be driven independently of each other, and wherein the first and second multi-junction SST chains are part of a single die.
2. The SST system of claim 1 , further comprising a driver configured to activate the first multi-junction SST chain when absolute voltage input is at least equal to the first drive voltage and activate the second multi-junction SST chain or the first and second multi-junction SST chains when absolute voltage input increases to a predetermined voltage level.
3. The SST system of claim 2 wherein the first drive voltage is less than the second drive voltage, and wherein the driver is configured to activate the second multi-junction SST chain alone when absolute voltage input is at least equal to the second drive voltage.
4. The SST system of claim 2 wherein the driver is configured to activate the first and second multi-junction SST chains when absolute voltage input is at least equal to a summation of the first and second drive voltages.
5. The SST system of claim 2 wherein the driver is an AC driver, and wherein the AC driver is configured to reverse polarity of voltage phase of an AC waveform.
6. The SST system of claim 2 wherein the driver is an AC driver, and wherein the SST system further comprises:
a third multi-junction SST chain and a fourth multi-junction SST chain operably coupled to the AC driver, wherein the third and fourth multi-junction SST chains are oriented in an opposite direction to the first and second SST chains; and
wherein the AC driver is configured to activate the first and second multi-junction SST chains in a first direction when a phase of an AC waveform is positive and activate the third and fourth multi-junction SST chains in a second direction opposite the first direction when the phase of the AC waveform is negative.
7. A lighting system, comprising:
a multi-junction light emitting diode (LED) die including a plurality of multi-junction SST chains, wherein each multi-junction SST chain has a P-contact, an N-contact, and a drive voltage, and wherein the first and second multi-junction SST chains are configured to be driven independently of each other; and
a driver independently coupled to the individual P- and N-contacts, wherein the driver is configured to drive at least one multi-junction SST chain when voltage input is at least equal to a first predetermined voltage level and drive a different and/or additional multi-junction SST chain when absolute voltage input increases to a second predetermined voltage level.
8. The lighting system of claim 7 wherein the driver is configured to serially activate the multi-junction SST chains as absolute voltage input increases, and wherein the driver is configured to serially deactivate the multi-junction SST chains as absolute voltage input decreases.
9. The lighting system of claim 7 wherein the driver is configured to drive one multi-junction SST chain at a time depending on the voltage input.
10. A solid-state transducer (SST) die, comprising:
a first multi-junction SST chain having a first drive voltage, a first P-contact, and a first N-contact, wherein the first P- and N-contacts are configured to connect to a first output of an AC driver; and
a second multi-junction SST chain having a second drive voltage, a second P-contact, and a second N-contact, wherein the second P- and N-contacts are configured to connect to a second output of the AC driver, and wherein the first and second multi-junction SST chains are configured to activated independently of each other.
11. The SST die of claim 10 wherein the first multi-junction SST chain is configured to be activated when absolute voltage input is at least equal to the first drive voltage, and wherein the second multi-junction SST chain or the first and second multi-junction SST chains are configured to be activated when absolute voltage input increases to a predetermined voltage level.
12. The SST die of claim 10 wherein the first and second multi-junction SST chains are two of a plurality of multi-junction SST chains, and wherein the drive voltage of each multi-junction SST chain increases from the first multi-junction SST chain to an n th multi-junction SST chain.
13. The SST die of claim 10 wherein the first and second multi-junction SST chains are two of a plurality of multi-junction SST chains, and wherein the drive voltages of the individual multi-junction SST chains are substantially equal.
14. The SST die of claim 10 , further comprising a third multi-junction SST chain having a third drive voltage, a third P-contact, and a third N-contact, wherein the third P- and N-contacts are configured to connect to a third output of the AC driver, and wherein the third multi-junction SST chain is oriented in an opposite direction to the first and second SST chains.
15. A method of operating a solid-state transducer (SST) system, the method comprising:
receiving a voltage at a driver;
activating a first multi-junction SST chain of a plurality of multi-junction SST chains when absolute voltage input is at least equal to a first predetermined voltage level, wherein the first predetermined voltage level is at least equal to a drive voltage of the first multi-junction SST chain; and
activating a second multi-junction SST chain of P-N junctions of the plurality of multi-junction SST chains of P-N junctions when absolute voltage input is at a second predetermined voltage level, wherein the second predetermined voltage level is at least equal to a drive voltage of the second multi-junction SST chain, and wherein the second predetermined voltage level is higher than the first predetermined voltage level, and wherein the plurality of multi-junction SST chains define a single SST die.