>
>Xicor has introduced a Bias regulator chip made especially for use
>with LDMOS RF transistors. It uses active feedback from a drain
>current sensing resistor, to adjust the gate bias to keep the part at
>optimal Q point for, say, class AB1 idling current. It has an
>interface port for digital control, to force it into various states
>such as active adjusting, PA shutdown, PA transmit without
>adjustment, etc. Internally the chip uses one of their digital
>controlled potentiometers to make the adjustment, and has an
>instrumentation amp front end, an error amp and an output buffer amp.
>Its the X9470. Heres the blurb from their website. There is a PDF
>file press release but no datasheet that I could find:
>
>>Xicor and Motorola Collaborate
>> On "Smart Biasing" Solutions for RF Power Amplifiers
>>
>> MILPITAS, California - January 16, 2002 - Xicor,
>>Inc. (Nasdaq/NMS: XICO)
>> announced today that they have teamed up with
>>Motorola to provide radio
>> frequency power amplifier (RFPA) reference
>>platforms for GSM, EDGE and
>> W-CDMA cellular basestation applications. These
>>reference platforms will
>> incorporate Xicor's unique "Smart Biasing" ICs for
>>RFPA applications.
>
>
>All the ricka-racka on screen voltage regulators for tetrodes
>reminded me to point out that the IC folks have it easy to build it
>all into a small ASIC device, while we tube types gotta fool around
>with MOSFETS, Zeners, spark gaps, and so on, to stabilize our beloved
>bottles. It sure would be wonderful if hams with huge egos would grow
>up and keep their contributions to AMPS@CONTESTING.COM at a
>technical, not personal, level.
// I view ad hominem attacks as good news. There's usually a tender
nerve behind technical bull's-eyes. Eliminate the "expert"
technoblatherers on AMPS and the group would likely be a sure cure for
insomnia.
> Its amazing how quickly the
>discussions seem to elevate to attack mode.
// As a wild and crazy guess, the problem might be related to
testosterone.
- In some primative tribes of New Guinea, men wear phallocarps -- i. e.,
holsters used to protect male equipment from thorns and brambles on
jungle trails.
- See *Discover* magazine, "April, 1985.pp,70-83 - "Everything Else You
Always Wanted to Know About Sex . . . But That We Were Afraid to Ask".
by Jared Diamond:
quoting:
" ... Phallocarps vary in length (up to two feet), diameter (up to four
inches), shape (curved or straight), ... ... ... Each man has a
wardrobe of several sizes and shapes. Western male anthropologists
interpret the phallocarp as something worn for modesty or concealment, to
which my wife had a succinct rebuttal: "The most immodest display of
modesty I've ever seen!"
>I'm sure certain individuals will send me a stab for suggesting that, but
.... just
>grow up.
>
// My favorite kvetcher is the guy who complains about reading my
replies.
cheers, John
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
end
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