HIGH POWER RF MOSFETs
SD2941-10 / SD2942 / SD2943: 175W and 350W under 50V supply voltage

These major improvements will give customers the possibility to use less active components (thus reducing the final cost) inside an amplifier chain designed to deliver a fixed Pout and gain level. All these products will be processed in the new 6” RF wafer fab which will ensure a higher level in terms of overall quality and service.

Just like the SD293X series, the new SD294X family makes use of “gold metallized N-Channel RF MOSFET technology”, where the old SD293X process layout has been redesigned in order to improve RF performance. In particular, the Crss (feedback capacitance) has been decreased by means of a shield structure, which allowed, with respect to the previous generation, a higher RF gain. Another major improvement has been made on the RDS(on) which has been decreased to achieve higher Pout; the Pout range now goes from 175W to 350W. These technology solutions are under exclusive patent rights. Of course, the well proven ruggedness and reliability of the previous generation have been maintained, as well as the lowest thermal resistance of the market, thanks to the use of “non pedestal” ceramic packages.

Gold metallization;
New patented process layout;
“Non pedestal” ceramic package;

Extremely rugged device performance;
High Pout in single package;
High gain;

Single side band (SSB);
FM / VHF broadcast;
Industrial laser;
Plasma generator for display panels;
Plasma generator for semiconductors;

	SD2941-10	SD2942	SD2943
Supply voltage	50V	50V	50V
Frequency	175MHz	175MHz	30MHz
Power Out	175W	350W	350W
Gain (Typ)	21.5dB	17.5dB	25dB
VSWR	10:1	5:1	5:1
Package	M174 Single-ended	M244 Push-pull	M177 Single-ended
Rth j-c	0.45°C/W	0.35°C/W	0.27°C/W

A comparison between the previous SD293X and the new SD294X family shows a big improvement in the overall RF performance. These results have been obtained thanks to the new process layout.

	SD2942	SD2932
Pout	350W Min	300W Min
Eff.	55% Min	50% Min
Gain	17 Typ	16 Typ

It is clear that significant results have been achieved concerning the main parameters. The higher Output Power capability in particular, is a great benefit for all the applications that this new family is addressing.

Company	P / N	Pout [W]	Eff [%]	Freq [MHz]
ST	SD2942	350	65	175
Philips	BLF278	300	>60	108
Ma / Com	MRF151G	300	50-55	175

The above comparison is a further confirmation of the top notch performance given by the new family. Three basic RF characterizations of the SD294X series are shown in the the graphs to the right. The top graph in particular shows a direct comparison between the old and the new generation. For the new family, we can estimate more than 1 dB increase in terms of Power Gain and more than 20% increase in terms of Output Power.