provided by: EDN
Infineon Technologieshas released the BGA728L7 broadband low-noise amplifier for portable- and mobile-TV applications. The BGA728L7 covers the VHF (very-high-frequency) III, UHF (ultrahigh-frequency), and L bands. It offers high- and low-gain modes. In high-gain mode, the BGA728L7 helps to improve reception sensitivity for weak signals through its noise figure of 1.4 dB and 16-dB gain. For a strong input signal, you can switch the BGA728L7 to low-gain mode to offer higher linearity with current consumption of 0.5 mA.
The main challenges for mobile-TV systems are to achieve high dynamic range, to enhance system sensitivity for indoor reception or tunnels, and to fulfill the stringent MBRAI (multibasic-rate-interface) requirements. The amplifier supports various standards, such as DVB-T (digital-video broadcast-terrestrial), DVB-H (digital-video broadcast-handheld), ISDB-T (integrated-services digital broadcast-terrestrial), MediaFlo, and T-DMB (terrestrial digital-multimedia broadcasting), as well as the emerging Chinese standards, including CMMB (China mobile-multimedia broadcasting), TMMB (telecommunication-mobile-multimedia broadcasting), and DMB-TH (digital-multimedia broadcast-terrestrial/handheld). The switching time of 3.5 msec allows the amplifier to support time-slicing-based mobile-TV systems.
The BGA728L7 supports a supply-voltage range of 1.5 to 3.6V. Due to the low-voltage and -current capabilities, the amplifier allows higher energy efficiency for portable devices and extends their battery-usage time. The on-chip 1kV HBM (human-body-model) ESD (electrostatic-discharge) protection simplifies the system's ESD-protection effort and makes the amplifier resistant to ESD events during assembly. The broadband amplifier integrates a high-performance silicon-germanium bipolar transistor and active-biasing, feedback, and I/O-matching circuits. It needs three external passive components, and you can use it to quickly build a compact, low-power mobile-TV design.
Infineon Technologies, www.infineon.com.
author: by Graham Prophet
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