Mal, Yes, putting several in parallel means that the total capacitance that the driver stage sees (sum of gate capacitances and the reverse transfer capacitances) increases so more power is needed to
An interesting circuit, but there is one thing that puzzles me. There is a lot of open loop gain as well as non-linear discontinuity in the drive that would contribute audio distortion. Just like
Hi Stefan, Thanks for the reference. Interesting schematics, but it is used to produce amplitude modulation. Feeding it PSK31 @ 500 KHz from the soundcard isn't going to get me very popular I suppose
Hello Mal and group! ....."a few in parallel".... My PA is using a single IRFP260N and if I want to put another one "in parallel" is it necessary to "decouple" the gates by two resistors (a few Ohms
Hi Minto, Am 13.01.2011 23:09, schrieb Minto Witteveen: Stefan, You mentioned the IXDD414 in a previous message here on the reflector, and I immediately downloaded the datasheet. The IXDD414 certainl
LF/MF It seems to me if you are working with low V high current FETS the RDS seems reasonable 0.02 for example but when a High V low current device is need the RDS of these devices seem to be around
Hello Minto! Thank you for the reply. That confirms my thoughts. I will try to put another transistor in parallel soon. 73 es tnx OE3GHB Gerhard Am Donnerstag, den 13.01.2011, 21:15 +0100 schrieb Min
Yup that is correct. High(er) voltage fets usually have the higher RDS-on values... Tradeoff based on physics... I started my 500-600 Watts 500 KHz transverter with two IRFP360's in parallel. Later I
Minto One approach is to use a few in parallel like they do in plasma tv's but there must then be other considerations to hinder the application. mal/g3kev better 54 seems the that conclusion at
Gerhard, It is my experience that using a separate resistor for each gate (abt 10 ohms) greatly reduces a tendency for parasitic oscillations. Main cause might be my particular setup but without the
Stefan, You mentioned the IXDD414 in a previous message here on the reflector, and I immediately downloaded the datasheet. The IXDD414 certainly looks very promising and I plan to experiment with it
Hi Gerhard, I know many people using a 1 Ohm to 4.7 Ohm resistor in series when paralleling the FETs. This is to prevent e.g. "oscillations" and is used in SMPS applications, switching at some 10 kHz
Minto, 14 nF gate capacity can easily be driven by a IXDD414, at 500 kHz and even at 1800 kHz. I've built a 600W class E for 160m running at 36 VDC (for /p, 3 car batteries in series ;-) ), using 4xI
