...
https://www.cree.com/led-components/media/documents/XLamp_PCB_Thermal.pdf
LED Drivers
Candidates:
https://www.digikey.com/product-detail/en/texas-instruments/TPS61161QDRVRQ1/296-25235-6-ND/2175022 (one channel, boost, very simple, could be too small to solder)
https://www.digikey.ca/product-detail/en/texas-instruments/TPS61165DBVR/296-27597-1-ND/2340765