BOM for O+C (rev 2d, 2e)

  • if your board is is labelled 2e (on top of the board, underneath the ‘ornament and crime’ label), that’s rev 2e. previous versions differ only slightly.
    • the BOM for rev 2c. can be found here
  • the footprint for passives is 0805 throughout. using 0603 everywhere will work just as fine, of course.

  • versions prior to 2e: 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: 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%
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 (0805) (25V or better):

value # type note
18p-22p 4x C0G/NP0 (!) e.g. mouser # 77-VJ0805A180GXACBC
330p-560p 4x C0G/NP0 e.g. mouser # 77-VJ0805A561JXAAC
100n 12x ceramic e.g. mouser # 80-C0805C104K5R
470n 3x ceramic e.g. mouser # 77-VJ0805Y474JXJTBC
1u 2x ceramic e.g. mouser # 581-08055C105K4Z2A
10u 4x ceramic (or tantal) e.g. mouser # 81-GRM21BR6YA106KE3L

ICs/semis:

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, 595-DAC8565IBPW, 595-DAC8565IDPW (††)
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
  • (††) they’ll all work. (grades C and D have slightly better specs (re temperature stability), but it won’t really matter here)

misc through-hole:

what # note part
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. 652-PEC11R-4220F-S24 (†)
2x5 pin header 1x 2.54mm (euro power connector) e.g. mouser # 649-67996-410HLF
1x7 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 # 517-929870-01-07-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 mouser #: 855-R30-1611000 (††††)
  • (†) rotary encoder w/ switch: for instance: mouser # 652-PEC11R-4220F-S24 (20 mm, ‘D’), 652-PEC11R-4220K-S24 (20 mm, knurled)).
  • (††) best to use “machined pin” ones (also called “round” or “precision”): the pcb holes are small. Or these sockets from RS-Online are a good alternative and will accept standard square-pin 0.1 inch pitch headers: http://au.rs-online.com/web/p/products/2304893/?sra=p&r=t
  • (†††) much cheaper is sos.
  • (††††) plus 2x 6mm 3M (hex) screws, or 1x ~ 16mm M3/hex screw + nut.

MCU/display:

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 7-pin, 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, or
    • GND - VCC - CLK - MOSI - RES - DC - CS, or
    • GND - VDD - SCK - SDA - RES - DC - CS
  • … then they should work (it’ll be the same OLED, just using different labels).
    • 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).