US 7,795,968 B1 · Power ranging transmit RF power amplifier

Abstract

An RF PA operable in two or more selectable power ranges is disclosed. Switches configure the circuit for each range such that an amplifier device corresponding to the range provides final amplification, and all lower power amplifier devices also amplify the signal. An exemplary design includes a low power amplifier configurable for operation solo, or in parallel with a medium power amplifier, to deliver an appropriately matched signal either directly to the RF PA output, or first to the input of a high power amplifier for the highest power range. The signal in all ranges of the exemplary design is conditioned in part by the matching circuitry disposed between the high power amplifier and the RF PA output, which traverses no switches in high power range operation. The entire RF PA, including switches, control and matching circuitry, is fabricated on a single monolithic integrated circuit, an achievement may be facilitated by UTSI CMOS processing.

Claims20

Dependent claims

An RF (radio frequency) PA (power amplifier) for amplifying an RF signal between a source node IN and an output node OUT in a selectable plurality of output power ranges including a low power range and a high power range, the RF PA comprising:

a) a low power active amplifier device configured as a final amplification stage when the RF PA operates in the low power range, and configured as a first amplification stage when the RF PA operates in the high power range;
and
b) a high power active amplifier circuit configured to conduct significant operating current and to amplify a signal previously amplified by the low power active amplifier device when the RF PA operates in the high power range, and configured to conduct less than 5% of the significant operating current when the RF PA operates in the low power range.

A method of amplifying an RF (radio frequency) signal between an input node IN and an output node OUT of an RF PA (power amplifier) in a selectable plurality of power ranges including a low power range and a high power range, comprising:

a) selecting a low power range, and while operating in that range
i) coupling a signal presented on the input node IN to an input of a low power active amplifier device,
ii) amplifying the signal between the input and an output of the low power active amplifier device, and
iii) coupling the amplified signal from the output of the low power active amplifier device to the output node OUT without further amplification,
b) selecting a high power range, and while operating in that range
i) coupling a signal presented on the input node IN to an input of the low power active amplifier device,
ii) amplifying the signal between the input and the output of the low power active amplifier device,
iii) coupling the amplified signal from the output of the low power active amplifier device to an input of a high power active amplifier device,
iv) amplifying the signal between the input and an output of the high power active amplifier device, and
v) coupling the signal amplified by both the low power active amplifier device and the high power active amplifier device from the output of the high power active amplifier device to the output node OUT.

7 more elements

Dependencies are inferred from the claim text.

Power ranging transmit RF power amplifier

Life of this patent

Power ranging transmit RF power amplifier

Life of this patent

Abstract

Claims20