Method for failure detection in a radio frequency device

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale.
For example, the dimensions of some of the elements are exaggerated relative to each other.
Further, where considered appropriate, reference numerals have been repeated among the figures to indicate corresponding elements.
This method of failure detection shown in FIG.
2 leverages off of the two ways a transistor will typically fail.
One is a gate short and the second is a drain short.
By looking for evidence of these two failure mechanisms one can detect a substantial majority of all device failures.
FIG.
2 illustrates a circuit diagram of a power amplifier 200 configured for enabling the status of an RF device in the amplifier to be detected in accordance with the present invention.
Power amplifier 200 preferably includes a MOSFET transistor 210, a RF de-coupling device (RFC) 236 connected to the gate 205 of transistor 210 and a RFC 238 connected to the drain 207 of transistor 210 that are both preferably inductors, a resistor 232 connected between RFC 238 and RFC 236; a resistor 234 connected between a common (ground) at a terminal 230 and the junction of resistor 232 and RFC 236, a fuse 240 connected between a voltage source V+ at a terminal 250 and the junction of resistor 232 and RFC 238, an RF matching circuit 212 connected to the gate 205 of transistor 210 for receiving an RF input signal (RFIN) at a terminal 220, and a RF matching circuit 262 connected to the drain 207 of transistor 210 through which a matched and amplified RF output signal (RFOUT) is presented at terminal 260.
In addition, the source of transistor 210 is coupled to an RF common (ground) at terminal 230.
Amplifier 200 is illustrated with one transistor for ease of discussion.
However, those of ordinary skill in the art will realize that amplifier 200 may also be implemented with additional transistors or with a different type of transistor, e