Amplifiers – With semiconductor amplifying device – Including field effect transistor
Patent
1987-06-01
1988-10-18
LaRoche, Eugene R.
Amplifiers
With semiconductor amplifying device
Including field effect transistor
330124R, 330295, H03F 316
Patent
active
047790601
ABSTRACT:
A power MOSFET linear amplifier includes a plurality of paralleled MOSFETS having a gate-to-source resistor to ensure simultaneous turn-on and sharing of the load current. An arc lamp is connected in series with a 400 volt power supply and a variable ballast element in the form of the power MOSFET linear amplifier. The linear amplifier includes four similar modules. Each module is a hybrid circuit constructed with eight MOSFETs connected in parallel. Each MOSFET includes a similar gate-to-source resistor in addition to an appropriate gate resistor and source resistor. Under operating load current conditions, the gate-to-source resistors are laser trimmed to establish precise equalized current sharing in response to the specified operating input voltages. The module is set with the gate voltage slightly above the operating threshold voltage range of the MOSFET. The modules then operate with the essentially simultaneous turn-on of all MOSFETs and in a reliable balancing of current between the several MOSFET devices. The modules are fabricated with a common heat sink and an appropriate packaging for rapid dissipation of the heat, to thereby maintain the necessary low operating temperature which is essential to reliable operation of the MOSFET devices.
REFERENCES:
patent: 4247824 (1981-01-01), Hilbourne
patent: 4554512 (1985-11-01), Aiello
"Paralleling of Power MOSFETS in Linear Applications" by Kim Gauen of Motorola, Inc., Semiconductor Product Sector, Phoenix, Ariz.
Gentron Corporation
LaRoche Eugene R.
Mottola Steven J.
Quantel International Inc.
LandOfFree
Linear power amplifying system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Linear power amplifying system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Linear power amplifying system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1197114