Maxim Integrated Products has introduced the MAX9930-MAX9933 low-cost, low-power logarithmic amplifiers that control RF power amplifiers and transimpedance amplifiers (TIAs), and detect RF power levels. These devices provide a choice of three different input-voltage ranges, thus eliminating the need for external attenuators and therefore simplifying amplifier control-loop design. The MAX9930-MAX9933 are designed to operate in the 2MHz to 1.6GHz frequency range and have a typical dynamic range of 45dB with an accuracy of ±1dB, making them useful in a variety of wireless and GPON fiber video applications such as transmitter power measurement and RSSI for terminal devices.
Logarithmic amplifiers provide a much wider, more accurate measurement range than controllers based on diode detectors. Each of these amplifiers measure voltage in a distinct, typical signal range: -58dBV to -13dBV (MAX9930/MAX9933), -48dBV to -3dBV (MAX9931), and -43dBV to +2dBV (MAX9932).
The MAX9930-MAX9933 consume 5.9mA with a 5V supply, and the typical shutdown current is 13 microamps. Furthermore, these devices feature a glitch-free output by asserting a power-on delay when coming out of shutdown. The MAX9930-MAX9933 are available in an 8-pin microMAX(R) package that achieves excellent temperature stability over the extended operating range of -40 degrees Celsius to +85 degrees Celsius.
Maxim Integrated Products
