The methodology offers a quick and accurate estimation of component values, giving more degrees of freedom to meet the design specifications. The concept of bias depression in HBT transistors is introduced with a bias circuit that reduces the bias-offset effect to improve linearity at high output power.Ī design methodology is presented for broadband matching networks, including the component loss. Multiple concepts for improving the linearity are presented, such as avoiding odd-degree harmonics, and linearizing the relationship between the output current and the input voltage of the amplifier at the fundamental frequency. The research investigates the linearity, and the nature and causes of nonlinearities. To our knowledge, this work provides the first implementation of class-J using GaAs HBT in a handset power amplifier. Class-J has been implemented using GaN FET in high power applications. The research applies a new technique to the handset industry, class-J, to improve the power efficiency while avoiding the practical issues that hinder the typical techniques (class-AB and class-F). Multiple techniques for improving the efficiency are investigated with the focus on maintaining linear operation. Three main areas of interest in power amplifier design are investigated: high power efficiency high linearity and broadband frequency response. The design techniques provide contributions to current research in handset power amplifiers, especially to the converged power amplifier architecture, to reduce the number of power amplifiers within the handset while covering all standards and frequency bands around the globe. The amplifier is thus able to operate in multiple modes (2G/2.5G/3G/4G). The power amplifier operates with high efficiency at the saturated output power, maintains high linearity with enhanced efficiency at back-off power levels, and covers a broadband frequency response. As you can see by the results, this amp is well suited for subwoofers or mid-basses as it has a nice amount of dynamic headroom for those transient peaks.This research presents design techniques for a linear power amplifier with high efficiency in wireless handsets. Here are the results from my test with the SMD/D'Amore Engineering AD-1 Amp Dyno:Ĩ ohms mono - 8 ohms - Amp is rated at 800W at 12VĨ ohms - Certified 1% THD - 818W at 13.99VĤ ohms mono - 4 ohms - Amp is rated 800W at 12VĤ ohms - Certified 1% THD - 824W at 13.5VĪll tests above were at 40Hz. Watch the video and see the results obtained from this 20yr old car audio amplifier. Quite an impressive feat, considering the competition! It may or may not surprise you, but the Linear Power came out on top. Other challengers were the Rockford Fosgate Power 1000 Mosfet, Precision Power 2350DM, Orion GS500 and HiFonics Colossus VII.quite a group of large, powerful, Class AB amplifiers! Since the 8002SW is a mono amplifier, the tester used 2 of these amps in the comparison. The Linear Power 8002 was also in a battle of "monster" amplifiers in the October 1991 Car Audio & Electronics magazine. Features biwired output terminals for feedback loop, which keeps speaker wire DC resistance from reducing damping factor defeatable subsonic filter soft turn-on/off fan cooling metal shroud. Specifications according to the 1991 Car Stereo Review Directory (July/Aug 1991): Linear Power 8002SW's Guts - TO-3 Transistors It is quite evident these amps are overbuilt and are more than capable of handling the additional load without breaking a sweat! If you read the original Linear Power manual, they caution against running the amp in 8 ohm mode powering 4 ohm speakers. After a call with Linear Power, it was suggested I set the amp to the 8 ohm taps to run the 8 and 4 ohm Dyno tests. Amp is less efficient in this mode and also produced less power. We initially ran all of the tests using the 4 ohm power supply taps, which lowered rail voltage and increased current. Unlike most of the mono amplifiers of today, this 8002 is capable of reproducing the entire 20Hz - 20kHz frequency range. It was available from 1991-1997 and sold at a MSRP of $1599. The Linear Power 8002 was an 800 Watt single channel amplifier optimized for 8 and 4 ohm loads. Early 90's Linear Power 8002SW 800W Mono Amplifier
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |