100MHz to 2500MHz, 45dB RF Detector in a UCSP

The MAX4003 low-cost, low-power logarithmic amplifier is designed to detect the power levels of RF power amplifiers (PAs) operating from 100MHz to 2500MHz. A typical dynamic range of 45dB makes this logarithmic amplifier useful in a variety of wireless applications including cellular handset PA control, TSSI for wireless terminal devices, and other transmitter power measurements. This logarithmic amplifier provides much wider measurement range and superior accuracy than typical diode-based detectors. Excellent temperature stability is achieved over the full operating range of -40°C to +85°C.

The MAX4003 logarithmic amplifier is a voltage-measuring device with a typical signal range of -58dBV to -13dBV. The input signal is internally AC-coupled by an on-chip 5pF capacitor in series with a 2kΩ resistance. This highpass coupling, with a corner at 16MHz, sets the lowest operating frequency and allows the input signal source to be DC grounded. The MAX4003 also features a power-on delay, which holds the detector output (OUT) low for approximately 5µs to ensure glitchless controller output.

The MAX4003 is available in an 8-bump chip-scale package (UCSP™), an 8-pin µMAX® package, and an 8-pin thin QFN package. The device consumes 5.9mA with a 3.0V supply and only 13µA when the device is in shutdown.

Applications

* Cellular Handsets (TDMA, CDMA, GPRS, GSM) * RSSI for Fiber Modules * Transmitter Power Measurement and Control * TSSI for Wireless Terminal Devices

* Complete RF Detector

* Frequency Range from 100MHz to 2500MHz

* Input Range of -58dBV to -13dBV (-45dBm to 0dBm into 50Ω )

* Fast Response: 70ns in 10dB Steps

* Low-Current Consumption: 5.9mA at VCC = 3.0V

* 13µA (typ) Shutdown Current

* Available in 8-Bump UCSP or 8-Pin µMAX and Thin QFN Packages