通用短距離無線采集卡設(shè)計文獻(xiàn)翻譯


HIGH SPEED OP AMPS
Walt Jung and Walt Kester
Modern system design increasingly makes use of high speed ICs as circuit building blocks. With bandwidths going up and up, demands are placed on the designer for faster and more power efficient circuits. The default high speed amplifier has changed over the years, with high speed complementary bipolar (CB) process ICs such as the AD846 and AD847 in use just about ten years at this writing. During this time, the general utility/availability of these and other ICs have raised the “high speed” common performance denominator to 50MHz. The most recent extended frequency complementary bipolar (XFCB) process high speed devices such as the AD8001/AD8002, the AD9631/9632 and the AD8036/AD8037 now extend the operating range into the UHF region.
Of course, a traditional performance barrier has been speed, or perhaps more accurately, painless speed. While fast IC amplifiers have been around for some time, until more recently they simply haven’t been the easiest to use. As an example, devices with substantial speed increases over 741/301A era types, namely the 318- amily, did so at the expense of relatively poor settling and capacitive loading characteristics. Modern CB process parts like the AD84X series provide far greater speed, faster settling, and do so at low user cost. Still, the application of high performance fast amplifiers is never entirely a cookbook process, so designers still need to be wary of many inter-related key issues. This includes not just the amplifier selection, but also control of parasitics

高速運(yùn)算放大器
　　沃爾特•榮格和華特迪
　　現(xiàn)代系統(tǒng)設(shè)計越來越多使用高速集成電路作為電路模塊的主要部分。隨著帶寬要求不斷增加,現(xiàn)代的設(shè)計師需要更快和更高效的電路。伴隨隨著高速度(CB)互補(bǔ)雙相性處理集成電路的發(fā)展，高速集成運(yùn)放的技術(shù)也發(fā)展了許多年。例如AD846 和AD847，它們的使用到現(xiàn)在已將近十年。在這段時間，普遍使用的放大器和其他的高效集成電路性能速度達(dá)到了50MHz。最近，具有寬頻率互補(bǔ)雙極性的高速 (XFCB)放大器,像AD8001 / AD8002,AD9631/9632和AD8036 / AD8037頻率已經(jīng)達(dá)到了超高頻。
當(dāng)然,傳統(tǒng)放大器的性能障礙就是速度，或者更準(zhǔn)確的說，在數(shù)據(jù)無失真下的速度。雖然利用高速集成放大器設(shè)計電路已有一定的時間，但是，直到最近他們才簡單而容易的應(yīng)用在實際應(yīng)用中。例如,以極大的速度設(shè)計的741/301A類型,即318 系列放大器,它們的速度很高，但是這樣做的代價就是相對低的穩(wěn)定性和負(fù)載電容特性。現(xiàn)代的互補(bǔ)雙相性處理集成模塊，使得像AD84X系列提供更高的速度,更快的轉(zhuǎn)換速度，同時也降低了用戶成本。然而，在實際應(yīng)用中，對高性能的高速運(yùn)放的設(shè)計并不簡單，因此設(shè)計師需要小心許多相關(guān)聯(lián)的關(guān)鍵性問題。這不僅僅包括放大器選擇,還包括周圍電路寄生效應(yīng)的影響和其它潛在的性能影響。