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Cheapest Prop board? — Parallax Forums

Cheapest Prop board?

RaymanRayman Posts: 14,844
edited 2012-04-02 03:38 in Propeller 1
Is the Quickstart the cheapest Prop board being sold?
I think it's $25 from Parallax, more through other vendors.

The new FTDI FT231 chip has me thinking about how cheap a Prop board could be...
I also noticed yesterday that Digikey has Props for $5 in qty. 100.

Haven't gone through the numbers extensively, but it seems that very basic Prop board could be made for ~$10 in parts...

$5 Prop
$2 FT231X
$1 USB connector
$1 EEPROM
$1 Crystal + passives

Add in a dollar or two for the PCB and maybe you have something that can be sold for $15?

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2012-03-30 06:26
    You may be able to buy the parts for $10 plus the PCB costs, but you can't realistically sell it for $15, not unless you're willing to essentially give away the cost of design, assembly, testing, etc. at the very least.
  • prof_brainoprof_braino Posts: 4,313
    edited 2012-03-30 06:42
    The design is more or less established, it would seem; just do it the way the other ones were done (Obviously I know little in this area).
    Assembly and testing costs could be eliminated if the board was sold as a bag of parts kit, and the user gets the fun of building the board.

    If one bought the parts in quantity, and was able to sell the kit for around the price of one-off parts and shipping, I would propbably go with the kit. $15 would be a great price.

    I would even ask for a unit that did not have the USB. I already have a prop plug and I only use it to program one board at a time. If that could be used, and the cost reduced further, I would still think it might be worth $15.
  • Martin_HMartin_H Posts: 4,051
    edited 2012-03-30 06:51
    The Gadget Gangster Propeller Platform board is essentially a bag of parts and a PCB, but sells for $35. If we assume the market is efficient then this says something about the costs of selling a board kit.
  • mindrobotsmindrobots Posts: 6,506
    edited 2012-03-30 07:20
    To Mike and everyone else's point, the material costs may be $12 - $15 but unless you want to lose money you would need to figure your costs further to reach your break even point. A flexible bare board design would be nice but once you star adding parts and distribution, it seems hard to beat a protoboard for cost vs utility.

    I'd probably go up to $8 for a bare board that I could add a dip prop, EEPROM, crystal, passives ans and option for USB ( w/ USB ) or a prop plug... But once you figure in design, manufacture and distribution costs, that might be a money loser.
  • LeonLeon Posts: 7,620
    edited 2012-03-30 07:21
    There are ARM boards with two Cortex devices (one for the JTAG and USB) that sell for $20, and make the supplier a profit.
  • RiJoRiRiJoRi Posts: 157
    edited 2012-03-30 07:25
    Yeah, you could sell it for $15, but you are forgetting overhead -- things like shipping & handling, boxes, bags, tape, record keeping, returns, etc.

    The pricing rule of thumb seems to be 2.5 times the material costs, so you should charge $30 for the $12 kit.

    --Rich
  • LeonLeon Posts: 7,620
    edited 2012-03-30 07:56
    That allows for distributors/resellers who usually want at least 30%. Selling direct means that the factor could be reduced.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2012-03-30 07:58
    I figure 5x parts cost for MSRP, which leaves room for two tiers of middlemen: mfr. -> distr. -> ret. -> user.

    -Phil
  • prof_brainoprof_braino Posts: 4,313
    edited 2012-03-30 08:04
    If its possible to come up with a $15 board, Rayman would be the one to do it. If it plus shipping is cheaper than the Quickstart at radio shack, he'd be the winner.
  • WBA ConsultingWBA Consulting Posts: 2,935
    edited 2012-03-30 09:51
    I sell my M44D40+ Module for $20 and I consider that a "non-profit" price. No on board USB or power supply. BOM cost is around $14 when including stacking headers. Factor in build, test, packaging, etc and you are at $20. The module started as a proof of concept and just a way for me to say I accomplished a "shippable project". I haven't marketed it much at all but still have sold around 40 in the past year. I have a few left from my most recent build and will probably make some more right before the expo to throw into the raffle as prizes.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-03-30 10:23
    When you take into account all of the overhead, production, etc, etc, the cheapest Propeller board is actually Quickstart. $25.00.

    OBC
  • RaymanRayman Posts: 14,844
    edited 2012-03-30 11:17
    I think I forgot about the 3.3V regulator... That's 50 cents extra...
    Maybe I'll think about a $16 to $19 board.
    (I think about a lot more stuff than I actually do :)

    Andrew, I like your board BTW. So, I guess $20 is the lowest priced Prop board around?
  • Nick McClickNick McClick Posts: 1,003
    edited 2012-03-30 11:39
    It's QuickStart; Because Parallax makes the Propeller, they can combine the margin of the chip and the QuickStart.

    For you, the Prop adds $6 to the BOM and maybe $10 to the final sales price. For Parallax, the Prop adds (maybe) $2 to the BOM and $4 to the final sales price.

    The Propeller Platform kit isn't the cheapest design possible - If you made a basic board (no USB, 3.3v only, one set of headers, no reset or power switch) as a kit, you could probably sell it for $25. But folks can already get a QuickStart, which is pre-assembled, includes USB, etc, for the same price. So how many basic kits would you expect to sell?
  • Cluso99Cluso99 Posts: 18,069
    edited 2012-03-30 12:56
    I sell the CpuBlade for US$17.50 assembled, or PCB for $2.50. I charge $3 to ship (airmail costs $2.45 and I have to make a trip to the PO and package it).
    Not that I promote it that much, but I have sold 1. I did this and a few others just for fun.

    The CpuBlade does not have an FT232 chip, but it does have the transistor reset circuit so that a cheap eBay USB-TTL (CP2102) board ~$4 can be used instead of a PropPlug. It has a 3V3 regulator but does require 5V input (readily available these days). Headers are supplied. The xtal is socketed and can be supplied as 5MHz, 6MHz or 6.5MHz (104MHz) and the board is designed for overclocking. http://www.clusos.com/home/1952.html
  • Invent-O-DocInvent-O-Doc Posts: 768
    edited 2012-03-30 13:09
    Consider that the prop proto boards (non-USB) go for $20/each in a five pack. They have all the stuff in them except for the SD-CARD socket and have dual voltage power.
  • RaymanRayman Posts: 14,844
    edited 2012-03-30 14:02
    Maybe it should have an uSD socket, but that adds ~$1.50. Might be worth it though...
    So, maybe I'll think about $19.99 and leave Cluso the lowest price winner...
    I think $19.99 with say $2 USPS shipping should be possible.

    The cost of the stencil and PCB fab setup fees are also killers, but if I can piggyback onto other projects, maybe it's possible.

    I think Quickstart was originally to be $20 and then went $25.
    As Nick points out, they do make the chip and save $6 there.
  • 4x5n4x5n Posts: 745
    edited 2012-03-30 15:13
    Rayman wrote: »
    I think I forgot about the 3.3V regulator... That's 50 cents extra...
    Maybe I'll think about a $16 to $19 board.
    (I think about a lot more stuff than I actually do :)

    Andrew, I like your board BTW. So, I guess $20 is the lowest priced Prop board around?

    Aren't protoboards $20 in qtys of 5?
  • jmgjmg Posts: 15,183
    edited 2012-03-30 15:44
    Rayman wrote: »
    Haven't gone through the numbers extensively, but it seems that very basic Prop board could be made for ~$10 in parts...

    $5 Prop
    $2 FT231X
    $1 USB connector
    $1 EEPROM
    $1 Crystal + passives

    Add in a dollar or two for the PCB and maybe you have something that can be sold for $15?

    Cheapest 3rd party board I've seen is the LPC-H11A14 at Mouser, $15 1+ and $12 5+
    So yes, Boards are being sold for $15.
    Perhaps NXP give them the LPC parts, in a contra-deal, or a volume price ?

    I like the LPC-H11A14 '4 sides' form factor, which keeps the PCB size down, AND gives user more IO pins...

    The Quickstart is good, but one beef is it has no 'shrink' option.
    Just a little more effort on the layout, and two saw cuts could make a much smaller one.

    I've seen Nuvoton manage the 'subset' question, with some well placed slots - sturdy, but makes the user-cut-choice very clear.
  • RaymanRayman Posts: 14,844
    edited 2012-03-30 16:39
    I just looked and the Prop Proto USB is $29 each... Didn't look at 5 pack though. Would a new user really buy 5?

    Is a really tiny board really the best? I'll have to double check the cost per square inch PCB, but I don't think it's too much.
    Wouldn't it be better to have place for people to solder in resistors and connectors to form audio, TV, and VGA outputs?
  • jmgjmg Posts: 15,183
    edited 2012-03-30 17:01
    Rayman wrote: »
    Is a really tiny board really the best? I'll have to double check the cost per square inch PCB, but I don't think it's too much.
    Wouldn't it be better to have place for people to solder in resistors and connectors to form audio, TV, and VGA outputs?

    There are really two steps in this :

    One is a first working device step, which is 'a device with a pulse' - this is minimal, but does need to not limit IO too much ( A weakness of USB stick type parts) .
    Get this right, and you will sell 5 packs

    Next up is a more functional board, Audio/TV/VGA are good, but given your work in the other thread with the SSD device, what about a stack system - in maybe the LPC-H11A14 form-factor.
    Can you fit the video chip + driver within that square, ( ~ 33mmx33mm) 38mm PCB and have the connector just outside ?

    The base board could fit a vertical Phono connector footprint, inside that ring ?

    I can see one error in the LPC-H11A14 form-factor, which is they seem to have made it completely symmetric, so there is no user-oops protection there.
    With 4 sets of pins, you can easily make it one-alignment only.
  • RaymanRayman Posts: 14,844
    edited 2012-03-30 17:23
    I just checked my last PCB order with ExpressPCB (yes, I know it's not the cheapest option).
    So, there was a $295 setup fee and then about 30 cents per square inch.
    The LCP thing is 6.2 square inches for $2.40.
    So, I guess that is about the right size board...

    Wait a minute... I don't get it, the LCP page says the size is:
    Dimensions:80x50mm (3.15 x 1.97")

    And yet, the PCB is square...
    http://www.olimex.com/dev/lpc-h11xx.html

    I really looks 1.5"x1.5"= 2.25 square inches. So, I think I can budget in a bigger board...
  • jmgjmg Posts: 15,183
    edited 2012-03-30 18:47
    There is a PDF here
    http://www.olimex.com/dev/ARM/NXP/LPC-H11XX/LPC-H1114.pdf

    That dimensions a 38mmx38mm square PCB
  • Duane DegnDuane Degn Posts: 10,588
    edited 2012-03-30 20:48
    Before the QuickStart boards and other less expensive boards were available, I used to buy these boards and and put my own components on them. By slicing one of the SMT pads on the back of the board, I could use a SOIC EEPROM. I'd also add pull-up resistors on the I2C line, crystal, bypass caps and a header for a Prop Plug.

    08879-03-L.jpg


    All the pins are broken out to the ring of holes around the board. I usually used a second small board with a voltage regulator stacked on top of this one as a power supply. I thought they made nice little Prop boards.

    Here's one I made to use with a breadboard (this one has a DIP EEPROM).

    BreadboardProp120314b.png


    I don't think I've made any this way since the QuickStart came out. Rolling my own with the above board with just too much work for the few dollars I'd save.
    08879-03-L.jpg
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    BreadboardProp120314b.png
    678 x 553 - 772K
  • WBA ConsultingWBA Consulting Posts: 2,935
    edited 2012-03-30 23:11
    @duane: Very nice, I really like the way you modified those boards for the Propeller. Reminds me of the Propmodule1x1 board that McTrivia use to sell that I used for my Plungelogger. I have also cut the center out of a Prop Proto board for a couple projects. (don't recall who came up with that idea)
  • lyassalyassa Posts: 52
    edited 2012-04-01 21:13
    I think the cheapest board for beginners would be what I am showing in the two pictures below. I used a protoboard before, but doing it the way in the pictures allows me to use the Propeller and the Prop-plug over and over again. Also, if I mess up my wiring, I simply throw the board away ($2.65 from Metro electronics in Sacramento) and start all over. True you end up with a rat nest, but so is the case when using a protoboard.

    front.jpg
    back.jpg
    front.jpg
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    back.jpg
    1024 x 768 - 86K
  • RaymanRayman Posts: 14,844
    edited 2012-04-02 03:38
    lyassa, that is a good point. But, I see a PropPlug in there...
    Just checked and it's now $14.99. So that, plus the Prop chip and other things is certainly going to be over $19.99...
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