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mxmxmx edited this page Apr 25, 2016 · 1 revision

#/* BOM for O+C (rev 2d) */

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

  • the footprint for passives is 0805 throughout. using 0603 everywhere will work just as fine, of course.

  • there's four 3-pin pads for 2k trimpots (output calibration): we recommend omitting the trimpots, and doing the calibration entirely in software. use four jumper wires instead and, ideally, 0.1% resistors for the output stage (the "wiki" has more details): it's cheaper and makes calibration easier (and no less accurate).

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%
49k9 6x e.g. mouser # 660-RK73H2ATTD4992F 1% / silkscreen says 2x 47k, 4x 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%)
  • (‡) if building with trimpots, use 24k (1%) rather than 24k9.

trimpots (throughhole):

value # type note
trimpot 50k-100k 1x cermet / inline / 9.5mm ADC/CV offset trim, for example
optional: trimpot 2k 4x cermet / inline / 9.5mm DAC output trim (omit: use 0.1% resistors instead)

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

value # type note
18p-22p 4x C0G/NP0 (!) e.g. mouser # 77-VJ0805A220GXAPBC
10n 4x C0G/NP0 e.g. mouser # 603-CC805JRNPO9BN103
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
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
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 ! 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
  • (†) rotary encoder w/ switch: for instance: mouser # 652-PEC11R-4215F-S24 (15 mm, 'D' shaft); 652-PEC11R-4215K-S24 (15 mm shaft, knurled); 652-PEC11R-4220F-S24 (20 mm, 'D'), 652-PEC11R-4220K-S24 (20 mm, knurled), etc).
  • (††) best to use "machined pin" ones (also called "round" or "precision"): the pcb holes are small.
  • (†††) much cheaper is sos.

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 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).