Renesas Hitachi 2SK1058 & 2SJ162 Lateral MOSFET

[billanichols]

Okay, I've searched these forums for the installation info on these MOSFETS, read the data sheets, but still have not found any information on the mounting orientation for these devices.

Here's my question. Do the 2SK1058 & 2SJ162 Lateral MOSFETs have to be mounted in the horizontal plane?

Your expert help will be appreciated.

[Xoc1]

I don't quite understand the question.
These lateral mosfets need to be mounted on a heatsink. They need to be isolated from the heatsink, or the heatsink needs to be insulated as it will be at output potential. Their orientation is down to the designer.
Due care needs to be taken on the way that they are connected to avoid RF instability. Gate resistors need to be close to the gate pin. Voltage rails need to be low impedance, and preferably have local decoupling capacitors to 0V. Source (output) connections need to link the source pins together with a low impedance. All of these physical conciderations will help to ensure that you don't build a radio transmitter.

[billanichols]

Originally Posted by Xoc1

I don't quite understand the question.

Thanks for the reply Xoc.

What I'm asking is can I mount the ESP P101 High Power MOSFET Amplifier Kit circuit board to a Conrad heat sink MF30 and with the fins running up and down. This will place the circuit boards and the MOSFETS in the horizontal plane.

And what's the difference between a lateral MOSFETS and vertical MOSFETS?

Thanks.

[Xoc1]

Lateral Mosfets have a negative temperature coefficient. They conduct less current as they get hotter. This makes them self-regulating. They do not require a bias that changes with temperature.
Vertical Mosfets have a positive temperature coeffcient. They conduct more current as they get hotter. This means they require a bias circuit with temperature compensation.
Lateral and vertical mosfets can not be swapped in an amplifier circuit without bias modifications as they also require differing bias voltages.
It has nothing to do with the orientation of the mosfets!

[sakis]

that ..... was a good one realy made my day

[Dr.EM]

Originally Posted by sakis

that ..... was a good one realy made my day

I concur


Actually seems quite hard to find these MOSFETs now. Reckon these would work in a P101:

ACD100NSD Lateral Mosfets - Class-d Limited

?

[Uunderhill]

Originally Posted by Xoc1

Lateral Mosfets have a negative temperature coefficient. They conduct less current as they get hotter. This makes them self-regulating. They do not require a bias that changes with temperature.
Vertical Mosfets have a positive temperature coeffcient. They conduct more current as they get hotter. This means they require a bias circuit with temperature compensation.

Xoc1,

Thanks for this clarification