antennaRFtexas instruments
I saw the following antenna layout in a Texas Instruments application note titled AN043, Small Size 2.4 GHz PCB Antenna. What is with the right angle the feed makes? Wouldn't that cause reflections? Or is this a special impedance tuning technique (Kind of doubt that though).
The circuit has four optocouplers between the emulator and the controlCARD. These optocouplers are specified as ISO7220A. The problem is that the transmission rate set by default to XDS100v1 (CCSv6) is 1 Mbps and the optocouplers max rate is 1 Mbps. The solution was to reduce the transmission rate. Anyway, an adaptation of the design is imposed, to implement the connection by optocouplers ISO7220C (maximum transmission speed is 25 Mbps).
Thanks @Andyaka for your interest!
To fully interpret this drawing, it's useful to know a bit about GTD (Geometric Dimensioning and Tolerancing).
In answer to your specific question, the numbers refer to the maximum (top) and minimum (bottom) dimensions. So the leg will be somewhere between 0.15mm and 0.3mm wide.
The box around a dimension (not this one) indicates that it's a nominal dimension (such as the pitch 0.65mm) or what is called a "basic dimension" in GD&T. The positional tolerance of the legs is specified by the box with the 0.13mm in it and refers to maximum material condition (beyond the scope of this answer, but see the link if you're interested). In essence it allows the leg to be more out of the position dictated by the nominal pitch if it's thinner, so a 0.15mm wide leg can be more out of position than a 0.3mm wide leg. That allows the manufacturer to minimize costs, yet still retaining what matters to the user (the actual metal of the leg should fall within the target).
I agree with others that you should be able to find a suggested footprint and that this is a standard package (though not SO8 given the relatively fine pitch).
Edit: This is a DCT package, here is TI's recommended footprint for it (from the TXS0102 datasheet):
Best Answer
Yes of course the 90 degree angle will cause reflections. Anything that isn't a proper transmission line of the right impedance will.
Question is, how much will it reflect and maybe it is low enough. Many times a design might not be perfect but that doesn't mean it's not good enough. I guess in this case the designers wanted flexibility so they placed some pads to place components. And this happened to be the result.