Data Sheet

ADL5906

10 MHz to 10 GHz, 67 dB TruPwr Detector

Rev. B

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FEATURES

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Accurate rms-to-dc conversion from 10 MHz to 10 GHz

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Single-ended ±1.0 dB dynamic range: 67 dB at 2.14 GHz

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No balun or external input matching required

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Response independent of waveform types, such as GSM-EDGE/

CDMA/W-CDMA/TD-SCDMA/WiMAX/LTE

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Logarithmic slope: 55 mV/dB

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Temperature stability: <±1 dB from −40°C to +125°C

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Operating temperature: −55°C to +125°C

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Supply voltage: 4.75 V to 5.25 V

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Sleep current: 250 µA

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Pin compatible with ADL5902 and AD8363

APPLICATIONS

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Power amplifier linearization/control loops

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Transmitter signal strength indication (TSSI)

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RF instrumentation

FUNCTIONAL BLOCK DIAGRAM

Figure 1.

GENERAL DESCRIPTION

The ADL5906 is a true rms responding power detector that has

a 67 dB measurement range when driven with a single-ended 50

Ω source. The easy to use input makes the ADL5906 frequency

versatile by eliminating the need for a balun or any other form of

external input tuning for operation up to 10 GHz.

The ADL5906 provides a solution in a variety of high frequency

systems requiring an accurate rms measurement of signal power.

The ADL5906 can operate from 10 MHz to 10 GHz and can accept

inputs from −65 dBm to +8 dBm with varying crest factors and

bandwidths, such as GSM-EDGE, CDMA, W-CDMA, TD-SCDMA,

WiMAX, and OFDM-based LTE carriers. In addition, its temperature

stability over the broad temperature range of −55°C to +125°C

makes it ideally suited for a wide array of communications, military,

industrial, and instrumentation applications.

Used as a power measurement device, VRMS is connected to

VSET. The output is then proportional to the logarithm of the rms

value of the input. In other words, the reading is presented directly

in decibels and is scaled 1.1 V per decade, or 55 mV/dB; other

slopes are easily arranged. In controller mode, the voltage applied

to VSET determines the power level required at the input to null the

deviation from the setpoint. The output buffer can provide high load

currents.

Requiring only a single supply of 5 V and a few capacitors, it is

easy to use and capable of being driven single-ended or with a

balun for differential input drive. The ADL5906 has a low 250 µA

sleep current when powered down by a logic high applied to the

PWDN pin. It powers up within approximately 1.4 µs to its nominal

operating current of 68 mA at 25°C.

The ADL5906 is supplied in a 4 mm × 4 mm, 16-lead LFCSP, and

it is pin compatible with the ADL5902 and the AD8363 TruPwr™

rms detectors. This feature allows the designer to create one

circuit layout for projects requiring different dynamic ranges. A fully

populated RoHS-compliant evaluation board is available.