Infineon Technologies Ag

Manfred Haberl

Carl Stephelbauer

Rainer Koller

Andreas Scheiber

Hans-Peter Fuchs

Gerhard Habring

In a transmission path having two discrete-value adjustable amplifiers, a first amplifier is set with a first gain factor and a second amplifier is set with a second gain factor. A signal is then applied to an input of the transmission path, and a level of a first output signal of the transmission path is ascertained and the second gain factor is altered. The first gain factor is changed in the opposite direction, so that a total gain factor of the transmission path remains substantially the same. The level of an output signal from the transmission path is then ascertained again with the new settings. An offset value is determined by comparing the levels of the first and second signals. As a result, the second amplifier can be calibrated using relative measurements and the first amplifier.

Method for determining an offset value for a gain of a transmission path, transmission path with adjustable gain, and use of the transmission path

A controllable amplifier is disclosed. The amplifier includes two current paths which couple an input to an output of the controllable amplifier. Each current path has a respective transistor which is connected as source follower. One of the two current paths is designed to be controllable. It is thus possible to adjust the attenuation and hence the overall gain of the source/follower circuit as a function of a set value for the overall gain (CTRL). The circuit can be used as a variable gain amplifier (VGA), or as a programmable gain amplifier (PGA), in radio-frequency transmitters.

Controllable amplifier and its use

An amplifier arrangement includes a variable-gain signal amplifier. A control block is used to process a control signal in order to set the gain. A trimming unit acts on the control block such that signals which are produced by the control block can be trimmed relative to one another in order to set the gain of the signal amplifier.

Growing community of inventors

Linz, Austria

Manfred Haberl