Resistor-based attenuator systems

An attenuator system, comprising:

• a variable impedance configured to provide an impedance from among a plurality of impedance states, the variable impedance comprising:
• a first port;
• a second port;
• a first switched impedance coupled between the first port and the second port, the first switched impedance comprising a first transistor;
• and
• a second switched impedance coupled between the first port and the second port and coupled in parallel with the first switched impedance, the second switched impedance comprising a second transistor;
• and
• a control circuit configured to control the variable impedance to an impedance state of the plurality of impedance states at least in part by providing a first output voltage to a control terminal of the first transistor to turn the first transistor on;
• wherein the first transistor is configured to have a channel impedance constituting at least 10% of a total impedance of the first switched impedance when the first transistor is turned on.

An attenuator system, comprising:

• an input configured to receive an input signal;
• an output configured to provide an output signal;
• an impedance network coupled between the input and the output and configured to generate the output signal at least in part by attenuating the input signal, the impedance network comprising:
• a first variable impedance comprising a first transistor, the first variable impedance configured to have a first variable impedance topology;
• a second variable impedance comprising a second transistor, the second variable impedance configured to have a second variable impedance topology different from the first variable impedance topology;
• and
• a control circuit coupled to the impedance network and configured to control an impedance of the first variable impedance and the second variable impedance.