BOM for O+C (rev 2c)

  • if your board is is labelled rev.2c (on top of the board, underneath the ‘ornament and crime’ label), that’s rev 2c. previous versions differ only slightly.

  • the footprint for passives is 0805 throughout, except the five 10n caps (0603). using 0603 everywhere will work just as fine, of course.

  • there’s five 3-pin pads for trimpots (input/output calibration): simply omit the trimpots; the calibration can be done entirely in software. use five jumper wires instead and, ideally, 0.1% resistors for the output stage (the “wiki” has more details): it’s cheaper and makes calibration easier.

SMD resistors (0805):

value # part note
100R 4x e.g. mouser # 279-1623096-1 1%
220R 4x e.g. mouser # 279-CPF0805B220RE1 1%
510R 2x e.g. mouser # 603-RC0805JR-07510RL 1-5%
2k 1x e.g. mouser # 660-RK73H2ATTE2001F 1%
10k 1x e.g. mouser # 660-RK73H2ATTD1002F 1-5%
24k9 4x e.g. mouser # 756-PCF0805R-24K9BT1 0.1% (‡)
33k 8x e.g. mouser # 660-RK73H2ATTD3302F 1%
47k 2x e.g. mouser # 660-RK73H2ATTD4702F 1%
75k 4x e.g. mouser # 660-RK73H2ATTD7502F 1% (silkscreen says 49k9: ignore)
100k 4x e.g. mouser # 279-CPF0805B100KE 0.1%
100k 8x e.g. mouser # 660-RK73H2ATTD1003F 1% (or simply get 12 x 0.1%)

SMD caps (0603) (16V) :

value # type note
10n 5x C0G/NP0 e.g. mouser # 81-GRM1885C1H103JA1D

SMD caps (0805) (25V or better):

value # type note
18p-22p 4x C0G/NP0 (!) e.g. mouser # 77-VJ0805A220GXAPBC
100n 12x ceramic e.g. mouser # 80-C0805C104K5R
470n 1x ceramic e.g. mouser # 77-VJ0805Y474JXJTBC
1u 2x ceramic e.g. mouser # 581-08055C105K4Z2A
10u 4x ceramic (or tantal) e.g. mouser # 81-GRM21BR6YA106KE3L


what # package part
MCP6004 1x (SOIC-14) mouser # 579-MCP6004T-I/SL
OPA2172 2x (SOIC-8) mouser # 595-OPA2172IDR, and see note (†) below
DAC8565 1x (TSSOP-16) mouser # 595-DAC8565IAPW, 595-DAC8565ICPW
MMBT3904 (NPN) 4x (SOT-23) mouser # 512-MMBT3904
1N5817 (diode) 2x (DO-41) e.g. mouser # 621-1N5817
LM4040 5v0 1x (SOT-23) e.g. mouser # 926-LM4040DIM350NOPB
ADP150-3v3 1x (TSOT) mouser # 584-ADP150AUJZ-3.3R7
LM1117-50 1x (SOT-223) mouser # 511-LD1117S50
  • (†) something fancier (= more suitable, $$) than TL072 should be used for the DAC output stage; using TL072 will be ok, but ideally, you want something with (very) low offset/noise/drift. for example: OPA2172, OPA2277

misc through-hole:

what # note part
470nF cap 1x RM5 (16V) e.g. mouser # 80-R82DC3470AA60K
22uF cap 2x RM2.5 (35V or better) e.g. mouser # 647-UPM1V220MDD1TD
inductor 1x 10uH e.g. mouser # 542-78F100-RC
jacks 12x ‘thonkiconn’ (or kobiconn) PJ301M-12
encoders 2x 24 steps w/ switch e.g. PEC11R-4215K-S0024 (†)
2x5 pin header 1x 2.54mm (euro power connector) e.g. mouser # 649-67996-410HLF
1x7 (1x8) OLED socket 1x 2.54mm, low profile but not “machined” sockets with round holes for the pins - the square header pins on most OLED carrier boards will not fit sockets with round holes. Use the low-profile sockets indicated here, or equivalent -> e.g mouser # 517-929870-01-08-RA
1x14 socket 2x 2.54mm, socket for teensy 3.x see note (††)
1x14 pin header (to match) 2x 2.54mm, header for teensy 3.x -
tact switches 2x multimecs 5E/5G mouser #: 642-5GTH935 (†††)
+ caps 2x multimecs 1SS09-15.0 or -16.0 mouser #: 642-1SS09-15.0, or -16.0
3mm spacer 1x ∅ 3M, 10mm -


what # note source
teensy 3.2 / 3.1 1x cut the V_usb/power trace! oshpark / mouser # 485-2756
OLED 1x SH1106 or SSD1306 / 1.3” / 128x64 see note (†)
  • (†) you can find these 1.3” displays on ebay or aliexpress for < 10$. as long as the description claims that they are SH1106 or SSD1306 and the pinout is: GND - VCC - D0 - D1 - RST - DC - CS, they should work (or GND - VCC - CLK - MOSI - RES - DC - CS, which is the same). make sure you get the right size: 1.3” (not 0.96”)!
  • alternatively, the hardware/gerbers folder has .brd/.sch files for a/the OLED carrier board. in that case, you’d need to get the bare OLED. for example here (though there’s cheaper options for getting bare OLEDs).