buying IC's in die package to save money

First try some other distributors -- DigiKey is great for small quantities, but I would look to Avnet, Arrow &c for better prices in large quantities.

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At those quantities, you should go directly to a distributor, not to Digikey. Go to the mfg's website to find out who distributes that part.

Meindert

To get bare die you'd have to go to the manufacturer or a company that specializes in bare die such as semidice.com. Chances are the bare known-good-die could cost more than the packaged equivalents. You might be able to get untested die and toss out the failed devices, testing the chips on board as you assemble them - a "dicey" proposition at best.

The recommendation from otheres to pursue "proper" distributions is appropriate. At 10k quantities, you shouldn't have a problem getting a solid quotes, even at under 10 cents each.

Chip-on-board techniques still require wire bonding and gold plating on your substrate (at least that's the way I did things with hydrid assembly way back).

The Pulsonix PCB software I use has chip on board design as an option. I've never used it, though.

Leon

Yes, it's do-able but not going to be very practical for you, and probably more expensive, not to mention less reliable, less flexible and with more start-up costs. My advice is to forgetaboutit.

Try combining all your purchases (particularly the semiconductors) and push some real distributors for competitive package prices. A $15-20K semiconductor order is not enormous, but it's big enough to get some attention. Combine your requirements for a 6 month or 1-year's worth of projected production and ask for a quote with scheduled releases if appropriate.

Best regards, Spehro Pefhany

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Is this something you can roll into a cheap low-pin-count microcontroller? Is this something you can put in a [C]PLD?

Can you tell us the count of gates and what sort they are; i.e. 1 x

74HC74, 2 x 74HC373, etc?

COB techniques are rarely (never?) used for 74LS/4000 series logic. You might make a hybrid that way, but never an entire appliance.

10K is also a small volume for a consumer product. In order for this production method to be cost-effective, you have to: 1) minimize the number of bonds - which means minimize the number of dice - which means in all examples I've seen reduce it to two or three large ICs. 2) be talking at least an order of magnitude larger volume. Sure, you can get 10K made, but in order for it to approximate "cheap" you'll need to do it in Asia, and 10K is at the bottom end of a MOQ there.

One sneeze and you are out of business.

Be sure to factor in the vacuum handling gear and the pick and place machine.

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