thefreeman’s HDR Anduril 2 high efficiency drivers - update : FWxA boost driver

I finalised the design of 3 different sizes of single cell boost driver :

  • BST15 : for 17+mm drivers, 60*0 inductor, 3333 RPP PFET, double sided, 1*AUX LED, also supports Mike C’s OTSM firmware.
  • BST18 : for 20+mm drivers, 60*0 inductor, 5060 RPP PFET, double sided, 3*AUX LED. With a BST18-FWxA version.
  • BST21 : for 23+mm drivers, 70*0/ 60*0 inductor, single sided with 3333 RPP PFET and an additional 5060 emplacement on the back. 4*AUX LED. With BST21-KRx version.

And I assembled two BST21s, one 6V and one 12V :


Then took some efficiency measurements, 12V3A, XAL7030 1.5uH, 3333 SISS61DN on the front for RPP :

With an additional 5060 DMP2003 on the back :

Lowering the inductor value to 1uH (5mΩ vs 8.4mΩ) :

6V6A, which as expected is more efficient :