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[Disclaimer: I'm a beginner.] I ordered this OV7740 camera chip from Digikey without really researching it, thinking maybe I could connect to it with a microcontroller. (I have only Arduino at this point).

Digikey part page
"Datasheet" link

I just took these photos, next to a penny.

One side of chip

The other side

How do you connect to that? Is there a name for that type of connection? Can it only be handled by robots, or is there something I can learn to do by hand that could connect to those 32 contact points?

The sides of that chip are about 2-3 mm.

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    \$\begingroup\$ That looks like a BGA surface mount component. You can solder them by hand using a hot-air rework station or using a reflow oven (can cheat by using a hot plate or toaster oven). \$\endgroup\$ – helloworld922 Jan 8 '13 at 4:52
  • \$\begingroup\$ @helloworld922 - I'd add this as an answer, I was going to mention using a hot air rework station also, but I'd just be repeating your comment. \$\endgroup\$ – Oli Glaser Jan 8 '13 at 5:06
  • \$\begingroup\$ Let me add to both comments above. The BGA surface mount component would be soldered to a matching set of 32 pads on a PC board. From reading the positing from RobN it seems apparent that he may not have been aware of this and was thinking more in terms of "how could I attach some wires to the camera chip?". \$\endgroup\$ – Michael Karas Jan 8 '13 at 6:00
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That looks like a BGA surface mount component. It is possible to solder these parts to a PCB by hand using a variety of different methods.

  • Use a hot-air rework station

rework station

  • Use a reflow oven. This can be a professional one, or more commmon for hobbyists is to build your own from a toaster oven or a hot plate. For really cheap you can try using the toaster oven/hot plate without any extra controlling circuitry, just carefully watch the process.

Note: If you use the second option, be sure NOT to use the same toaster oven/hot plate for cooking food you're planning on eating or feeding to someone else.

Whichever method you choose you'll want to get a pair of very fine point tweezers, or even better a vacuum pickup tool.

pickup tool

You'll also want some kind of magnifying system. This allows you to precisely align components. Some people use a headband magnifier, others use a full-on desk microscope.

Soldering BGA packages also usually requires solder paste and flux.

You can get breakout prototyping boards for BGA packages, these are a basic PCB board which route the BGA's pinout to some through-hole pins you can solder headers or wires to.

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This is a BGA (ball-grid array) package. It's soldered by automated pick&place equipment or special BGA rework station. After soldering, it's usually X-rayed to check for defects. It's not meant to be soldered by hand.

There's a particular type of SMT prototyping board called Schmartboard. Guys who make it claim (in this video) that it can be used for hand-soldering BGA packages.

There are sockets for BGA chips (somewhat similar to ZIF sockets for DIP), but they can be very expensive.

Also, you could look for a breakout board (or a development board) for your sensor. The sensor would be professionally soldered onto the board.

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This could be described as a Chip Scale Package (CSP), as the "package" is just larger than the chip itself. It is also a Ball Grid Array (BGA) package, as it is designed to be attached to a printed circuit board (PCB) by reflowing the solder balls you see on the bottom of the package to pads on a PCB (and the solder balls balls are arranged in a grid pattern).

A "robot" is not required to place or reflow the device, but professional quality "pick and place" and reflow equipment make the job easier. These "pick and place" machines can be manually actuated or automated (robotic), as can the reflow equipment. I would not try to approach this task with a hand-held soldering iron.

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It is possible but likely difficult. Best approach I would consider is to create the PCB as it should be and then apply a little paste manually to the device, place it carefully on the board and reflow using a skillet. Using a skillet will make the heat come from below, avoiding possible damage to the top of the package where the imager is. Also, it will allow it to center itself due to surface tension. Make sure you have plenty of flux since it'll help avoid shorts.

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you could solder small jumper wires to the pins you need and stick them into your breadboard, this would be the easiest method i believe...

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    \$\begingroup\$ You're actually wrong. The wires are very likely to short and they're very difficult to place. With a little mechanical movement, they can tear a BGA ball off. Might look easier, but in the end you'll be pulling your hair out in frustration. \$\endgroup\$ – Gustavo Litovsky Jan 8 '13 at 17:23
  • \$\begingroup\$ Not the easiest method, but it is possible. xevel.fr/blog/index.php?post/2012/11/10/… Granted, that's a 3x3 with no inside ball, but it can be done. \$\endgroup\$ – Passerby Jan 8 '13 at 18:39

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