DVGAs from National Semiconductor Enable Higher-Performance Basestation Radio Architectures

National Semiconductor Corp. (NYSE: NSM) today introduced a pair of quad- and dual-channel, digital variable gain amplifiers (DVGA) that enable higher-performance wideband radio systems. The LMH6522 quad and LMH6521 dual DVGAs  provide superior linearity performance over a wide frequency range, making them an ideal solution for the most challenging multi-channel wideband wireless systems. Target applications include intermediate frequency (IF) sampling receivers, I/Q digital pre-distortion (DPD) signal paths and wide-bandwidth direct-conversion radios used in multi-carrier GSM, TD-SCDMA, W-CDMA and LTE wireless basestations.

Radio designers face the challenge of producing cost effective anti-alias filters (AAF) that meet the demanding requirements of today’s wider radio bandwidths. The flexibility to select from a range of filter impedance levels, including low impedance levels such as 50-Ohms, not only simplifies the AAF design, but also improves performance and manufacturability. National’s DVGAs are optimized for driving a wide range of load impedances. Their low-Z output drive delivers exceptional signal fidelity and provides the additional power gain needed when driving low impedance filters.

The LMH6522 and LMH6521 are well-suited for driving high-speed ADCs, including National’s ADC16DV160 dual 16-bit, 160 MSPS converter. In addition, the LMH6521 is ideal for driving National’s ultra-high-speed ADC12D500/800RF 12-bit, 500 MSPS/800 MSPS direct RF-sampling ADCs. By adding the LMX2541 frequency synthesizer and one of National’s family of LMK04800 or LMK04000 clock jitter cleaners, a designer can form a complete signal path.

Key Features of the LMH6522 Quad DVGA
•    OIP3: 49 dBm at 200 MHz input frequency
•    Precise 1 dB gain steps over a wide 31 dB range
•    Noise figure of 8.5 dB at maximum gain
•    Supplied in a 54-pin LLP® package

Comments

Post a Comment

Popular posts from this blog

What is Class I Division 2?

Image
A Class I Division 2 is a location: (1) In which volatile flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems or in case of abnormal operation of equipment, or (2) In which ignitable concentrations of flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment. Class I Division 2 Classification Class I Division 2 refers to the ANSI/ISA 12.12.01 standard. This standard was previously UL1604 until UL recommended the newer ANSI/ISA standard be used and that all hazardous location products be certified under this standa
Read more

FUSE SIZING CONSIDERATIONS FOR HIGHER EFFICIENCY MOTORS

Image
When selecting the proper fuse for short circuit protection in motor starting applications, it is important to not only ensure that the fuse will not nuisance open during motor start up times, but also that the fuse will coordinate as required with overload relays. When sizing fuses between 125% and 150% of the motor nameplate current, several advantages, including ease of coordination with an overload device, a smaller disconnect, and increased short circuit protection from a lower fuse rating, can be achieved. However, if sizing at this level prevents the motor from starting, it may then be necessary to increase the fuse ampere rating and it then becomes important to know the NEC sizing limitations. As of June 1, 2016, the US Department of Energy has mandated that newly manufactured electric motors will need to meet NEMA Premium® efficiency standards. As motor efficiencies increase, motor locked rotor currents can also be expected to increase. In addition to this, with across-the-lin
Read more

7/8 16UN Connectors that Provide 600 Volts and 15 Amps

TURCK announces new A-Size 3 and 4-pin 7/8 16UN powerfast™ connectors that provide up to 600 Volts and 15 Amps of power. These IP67 rated connectors provide a modular wiring system designed to handle high current applications for machine power distribution, while providing resistance to vibration commonly associated with conveyors, motors and material handling applications. The cordsets are available with a tray rated, exposed run PVC flexlife ® cable, with or without STOOW rating, and 14 AWG wires that allow you to replace hard wiring with a robust, quick disconnect system that saves the time and money spent installing a conduit system. The A-Size powerfast line offers male and female, straight connectors, standard and custom lengths, and pigtails or extensions. To make the system complete, fully encapsulated mating receptacles, with 1/2”-14 NPT mounting threads are available.
Read more