National Semiconductor introduced a pair of quad- and dual-channel, digital variable gain amplifiers (DVGA) for wideband radio systems. The LMH6522 quad and LMH6521 dual DVGAs provide superior linearity performance over a wide frequency range, making them a 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.
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 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
Key Features of the LMH6521 Dual DVGA
- OIP3: 48.5 dBm at 200 MHz input frequency
- Channel gain/phase matching of +/- 0.04 dB / +/- 0.45 deg
- Precise 0.5 dB gain steps over a wide 31.5 dB range
- Noise figure of 7.3 dB at maximum gain
- Supplied in a 32-pin LLP package
Pricing and Availability
Available now, the LMH6522 is priced at $9.85 and the LMH6521 is $6.15, both in 1,000-unit quantities.
