Baseband Tones Intermodulation
Intermodulation of Two Baseband Tones This is part 3 in series of two tone intermodulation distortion. When we usually talk about two tone intermods, we mean it for two RF tones for which 2nd harmonics or even order terms fall far away, and we say we only care about IM3 and IM5 because they are close […]
Intermodulation Distortion Analysis
Advance Intermodulation Distortion Analysis This is part 2 in series of two tone intermodulation distortion analysis. Whether you are optimizing linearity or debugging it, you want to understand what are different distortion products, how do they get generated and what are they made of. For example, IM3 is made of odd order non-linearities: 3rd order has […]
RFIC Transformer Model
Integrated Transformer Models We decided to write this article because there are only so many different models of a transformer that exist. Analog IC designers, RFIC designers and mm-wave IC designers – they all understand transformers a little differently. Enough is enough. We are putting together a list of different models (with derivations of course) […]
Semiconductor Yield Estimation
Semiconductor Yield Estimation Say you have an amplifier with Gain spec of x dB and you want to understand how many chips will pass this spec. What do you do? You measure all the parts you have, count the parts where gain fell below x dB and divide it to total number of parts, and […]
Single Tone Distortion
Distortion of a Single Tone in a non-linear System How does a single tone gets distorted in a non-linear system, what distortion products it generates and some insights into what goes in signal gain. Assume a non-linear system which can be modelled using a polynomial: $$V_o = a_o+a_1V_i+a_2V_i^2+a_3V_i^3+a_4V_i^4+a_5V_i^5$$ Let’s excite it with a single tone: […]
Intermodulation of Two Tones
Intermodulation of Two Tones Admit it. You are lazy and don’t make notes. You do this math every time you need to remember what distortion products are generated by intermodulation of two tones and what is their relative level. No more. We are doing the math now, so you don’t have to. Intermodulation Math Assume […]