| US 7,576,612 B2 | ||
| Power amplifier | ||
| Shigeki Nakamura, Osaka (Japan); and Junji Ito, Osaka (Japan) | ||
| Assigned to Panasonic Corporation, Osaka (Japan) | ||
| Filed on Dec. 18, 2007, as Appl. No. 11/958,966. | ||
| Claims priority of application No. 2006-340277 (JP), filed on Dec. 18, 2006. | ||
| Prior Publication US 2008/0143445 A1, Jun. 19, 2008 | ||
| Int. Cl. H03F 3/04 (2006.01) | ||
| U.S. Cl. 330—296 | 14 Claims |
| 1. A power amplifier comprising:
an RF operation transistor having a base to which an RF signal is inputted, an emitter connected to the ground, and a collector
connected to a power supply and a terminal for outputting an RF signal;
a current reference transistor having a collector connected to a reference current source, an emitter connected to the ground,
and a base connected to the base of the RF operation transistor;
a starting resistor connected between the base and the collector of the current reference transistor;
an operational amplifier formed of CMOS having one input connected to the collector of the current reference transistor and
the other input connected to the base of the RF operation transistor; and
a voltage-to-current conversion transistor for converting an output of the operational amplifier to a current, the current
being supplied to the base of the RF operation transistor.
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