Broadband communications applications can cover large portions of bandwidth in small packages, often requiring multiple amplifiers to provide gain. But when one amplifier can deliver suitable gain across a wide-enough bandwidth, that one amplifier may be sufficient to handle multiple applications within a single product.
Such is the case with the model GVA-123+ monolithic amplifier from Mini-Circuits. Based on gallium arsenide (GaAs) heterojunction-bipolar-transistor (HBT) technology, it covers 10 MHz to 12 GHz with 16.9 dB typical gain at 2 GHz and typical gain flatness of ±0.7 dB from 50 MHz to 8 GHz. This economical amplifier is supplied in an SOT-89 housing for excellent thermal stability.
The RoHS-compliant model GVA-123+ (see figure) provides a frequency range covering many of the wireless communications bands in a single amplifier, including cellular and WiMAX frequencies, and it is also well suited for use in satellite communications (satcom) systems and in test equipment.
The amplifier exhibits typical gain of 16.2 dB at 50 MHz, 16.9 dB at 2 GHz, 16.4 dB at 6 GHz, 16.3 dB at 8 GHz, and 12.5 dB at 10 GHz, dropping to 7.1 dB at 12 GHz. The output power at 1-dB compression is typically +15.9 dBm at 50 MHz, +16.2 dBm at 2 GHz, +13.4 dBm at 6 GHz, +10.3 dBm at 8 GHz, and +7.4 dBm at 10 GHz, again dropping to +5.1 dBm at 12 GHz.
The output third-order intercept point (IP3) is typically +30.2 dBm at 200 MHz, +29.9 dBm at 2 GHz, +24.5 dBm at 6 GHz, +21.8 dBm at 8 GHz, +19.1 dBm at 10 GHz, and +14.9 dBm at 12 GHz. Although this is not meant as a low-noise amplifier, the noise-figure performance is respectable, with typical noise figures of 3.8 dB at 200 MHz, 4.0 dB at 2 GHz, 4.4 dB at 6 GHz, 4.9 dB at 8 GHz, and rising somewhat to 6.9 dB at 12 GHz.
The model GVA-123+ features good input and output return loss without additional external impedance-matching components, and with input/output return loss of typically 20 dB at 2 GHz. The reverse isolation is typically 20.7 dB at 6 GHz. The compact, broadband amplifier is rated for 0.34 W maximum power dissipation and draws 52 mA typical current at +5 VDC, with maximum current consumption of 100 mA at +5 VDC. The robust amplifier is designed for use at operating temperatures from -40 to +85°C, maintaining good gain stability across that temperature range.
Mini-Circuits, P.O. Box 350166, Brooklyn, NY 11235-0003; (718) 934-4500, FAX: (718) 332-4661