The TS613, manufactured by STMicroelectronics, is an operational amplifier (opamp) suited especially for use in ADSL modems (according to its datasheet). And indeed, I found this little chip inside an old ADSL modem, a Thomson Speedtouch 510. In this digital world it's quite interesting to look at an analogue chip, especially a high-performance chip like this one. So, let's open it up and look what's inside!

An overview of the complete IC. It's nicely symmetrical, because there are two identical opamps inside. What's typical about an analogue chip is that there are many different sized transistors, and that they don't come in groups of ten thousand! Just a hundred or so are enough for this chip. We also see other things like capacitors (the brown squares) and very irregular wiring patterns.

A close-up of the bottom right. These brown squares are probably capacitors, and there are likely a few resistors on this picture as well, like the dark area at the centre-left.

The manufacturer's logo. The blocks above it are probably the driver transistors. These are the last transistors in the amplifier, and they have to provide all the output current. This opamp can provide quite a lot of current (200 mA), so the transistors are very big.

Here's a close-up of one output transistor. It's actually made up of a number of smaller transistors (which are still huge compared to the tiny ones that live on the rest of the chip) placed in parallel, so they can share the output current.

This is a resistor, the one you can see on the left of picture #2 above. It consists of several stretches of polysilicon (resistive material) laid end-to-end to create a relatively large resistance.

Here we can see a number of different transistors. There are four small bipolar transistors in the centre, connected to the resistors on the right. On the left, there are four bigger transistors.