Patent ID: 8558613
Filing Date: 2013-10-15
Classification: H03G,H04L

Abstract:
1. An apparatus comprising: an input node configured to receive an input signal; an output node; a programmable gain amplifier (PGA) having an input electrically coupled to the input node, and an output electrically coupled to the output node, the PGA being configured to amplify the input signal with an adjustable gain; and a gain control block having an input electrically coupled to the input node, the gain control block being configured to adjust the gain of the PGA based at least partly on an observed amplitude envelope of the input signal from the input node such that the PGA generates an output signal with a substantially constant amplitude envelope to the output node, wherein the PGA comprises two or more transconductance units, each of the transconductance units being electrically coupled in parallel between two nodes of the PGA, wherein the PGA is configured to select at least one of the transconductance units to provide at least part of the gain of the PGA, at least partly in response to a control signal from the gain control block.