Quantity   Component name
1 × ATtiny85 (eventual main microcontroller) Microprocessors, Microcontrollers, DSPs / ARM, RISC-Based Microcontrollers
1 × Inductor (LED driver circuit component) Playing with various values - 1mH, 3.3mH, 6.8mH, 10mH. Low ESR is desireable.
1 × Optional - digital multimeter Limited utility in measuring the actual voltages and currents used
1 × Optional - oscilloscope For useful analysis of the LED driver circuit - mine is a cheap DSO 138 kit and does the trick
1 × Arduino Nano clone For convenient USB-enabled design work where I want to test code (e.g. edit the pulse lengths and frequency) conveniently
1 × 300 Ohm resistor This is current limiting while I use the 5V logic pin on the Nano to drive the MOSFET that's connected to the 3.3V rail.
1 × Low value resistor (e.g. 40 Ohm) For eventual pin current limiting between the ATtiny85 and MOSFET gate
3 × N channel MOSFET (LED driver circuit and protection circuits component) Currently using the low RdsOn IRLB8743PBF in TO220 package.
1 × LEDs (TBC both type and number) Prototype 1 is using 5730 yellow Chanzon LED in 1,2,3,4
1 × PCB (TBC)
1 × Battery (TBC - likely protected lithium ion 18650)
1 × Battery charge controller (likely based on TP4056)
1 × Essential protection - pull-down resistor for MOSFET gate If the gate voltage is left floating, you can get a significant current running through the inductor and MOSFET while the microcontroller boots up. Need to check this won't add a parasitic load. 10K Ohm if not parasitic. Try 1M Ohm if parasitic.