Oshpark Projects

You might want to add this one to the OP. Over the past few months, I've been slowly working on an update to the original BLF SRK FET driver (design by Mattaus; development ideas from Comfychair and many others).

I present to you, the shiny new BLF SRK FET driver.

REQUIRED Parts List (1S Input):

  • FET: D2PAK
  • RGATE: 0805 - 10 ohm - 50 ohm
  • R1: 19.1K (1S input)
  • R2: 4.7K
  • U1: attiny13a-SSU
  • C1: 0805 - 10uF - X5R (or better)
  • D1: SOD-323 Schottky Diode

REQUIRED Parts List (2S+ Input):

  • FET: D2PAK
  • RGATE: 0805 - 10 ohm - 50 ohm
  • R1: 36K (2S-3S input)
  • R2: 4.7K
  • U1: attiny13a-SSU
  • C1: 0805 - 10uF - X5R (or better)
  • CLDO: 0805 - 10uF - X5R (or better)
  • LDO: Many fit - choose on price and availability

OPTIONAL Parts:

  • 7135: Optional 7135 for secondary PWM output (Pin 5)
  • OTC (for clicky FW use): 0805 - 1uF - X7R
  • Ctemp: 0805 Capacitor
  • RT1; RT2; T-; T+: Connection points and related component pads for external temperature sensor

Changes from original:

  • Additional vias
  • Deleted L1 and D1 pads (they were mostly unused)
  • Added more LED pads
  • Added optional 7135 on secondary PWM channel
  • Added optional LDO for 2S+ use
  • Changed ADC LVP feed point; now connected directly to input
  • No more jumpers or solder bridges needed for switch pads
  • SW- and several other low current pads now have thermal relief for easier soldering
  • Added optional OTC pad for clicky use
  • Added external temperature sensor provisions
  • Added gate resistor / pulldown resistor for big FET