| 摘要 |
Fast turn-on radio frequency (RF) amplifiers are disclosed. An RF amplifier system includes an amplification path comprising a switch FET 104 and an amplifier FET 102. To enable the amplification path, the switch 104 and the amplifier 102 may be turned on by signals 130 and 134, respectively. To reduce the insertion loss of the switch 104, a negative bias signal 132 may be applied to the channel of the FET 104. The negative-going edge of this signal may propagate through the dc blocking capacitor C2, undesirably slowing the turn-on time (140, fig.6) of the amplifier. The invention compensates for this effect by passing the positive-going edge of a compensating signal 152 through a capacitor C3, thus speeding up the rise time 160 of the amplifier. The invention thus compensates for a slow turn-on of the amplifier resulting from a signal applied to the switch, and provides good switch performance and fast amplifier turn-on. These characteristics are desirable in wireless LAN (WLAN) applications. |
