Linear buffer
AssigneeBroadcom Corporation
InventorsTodd Brooks, Anilkumar Tammineedi
Life of this patent
Estimating the term…
Abstract
A source-follower transistor based buffer provides high linearity. A replica transistor is used to generate a replica voltage substantially equal to the output voltage of the buffer. The replica voltage is level shifted by a level shift circuit and applied at the drain of the source-follower transistor to improve the linearity of the buffer. The buffer may be used in conjunction with a switched-capacitor sampling circuit. A damping circuit may be used to reduce charge glitches due to sampling. The damping circuit may be a low pass filter. The buffer may be used in an interface circuit that produces an output signal from an input signal and controls the level of the output signal.
Claims22
1-4. (canceled)
An interface circuit for producing an output signal from an input signal and a reference signal, wherein the output signal has an output direct current (dc) voltage level that is substantially equal to a dc voltage level of the reference signal, the interface circuit comprising:
- a level translation module adapted to generate an input level control signal from the reference signal;
- a level adjustment module adapted to produce an adjusted buffer input signal from the input signal, wherein the adjusted buffer input signal has a dc voltage level that is substantially equal to a dc voltage level of the input level control signal;
- and
- a buffer adapted to generate the output signal from the adjusted buffer input signal.
15-18. (canceled)
An apparatus that provides an output signal based on an input signal and a reference signal, comprising:
- a level translation module to generate an input level control signal having a first dc level that is based on the reference signal;
- a level adjustment module to provide an adjusted buffer input signal based on the input signal and the input level control signal, wherein the adjusted buffer input signal has a dc level that is substantially equal to the first dc level;
- a buffer to provide the output signal based on the adjusted buffer input signal.
Dependencies are inferred from the claim text.