Abstract: A switched capacitor circuit includes a threshold detector to generate a threshold detection signal when a difference between first and second input signals crosses a predetermined level. A variable current source produces a varying amount of current in response to the difference between the input signals. A voltage measurement means produce a measurement signal in response to the difference between the input signals. A correction means produces a correction signal in response to the measurement signal to produce an optimum coarse phase overshoot. A timing comparison means produces a timing signal in response to the difference between the input signals. A correction means produces a correction signal in response to the timing signal to produce an optimum coarse phase overshoot.
Type:
Application
Filed:
January 3, 2011
Publication date:
July 14, 2011
Applicant:
CAMBRIDGE ANALOG TECHNOLOGIES LLC
Inventors:
Matthew Z. Straayer, Hae-Seung Lee, Kush Gulati, Carlos E. Munoz
Abstract: A sample-data analog circuit includes a level-crossing detector. The level-crossing detector controls sampling switches to provide a precise sample of the output voltage when the level-crossing detector senses the predetermined level crossing of the input signal. A multiple segment ramp waveform generator is used in the sample-data analog circuits. The ramp waveform generator includes an amplifier, a variable current source, and a voltage detection circuit coupled to the current source to control the change in the amplitude of the current. The ramp generator produces constant slope within each segment regardless of the load condition. The sample-data analog circuit also utilizes variable bandwidths and thresholds.