LT5570 Datasheet, PDF (1/16 Pages) Linear Technology – Fast Responding, 40MHz to 2.7GHz Mean-Squared Power Detector

FEATURES
n _{Frequency Range: 40MHz to 2.7GHz}
n _{Accurate RMS Power Measurement of High Crest}
Factor Modulated Waveforms
n _{Linear DC Output vs Input Power in dBm}
n _{Linear Dynamic Range: Up to 60dB}
n _{Exceptional Accuracy over Temperature: ±0.3dB}
n _{Fast Response Time: 0.5μs Rise Time,}
8μs Fall Time
n _{Low Supply Current: 26.5mA}
n _{Low Impedance Output Buffer Capable of Driving}
High Capacitance Load
n _{Small 3mm × 3mm 10-Lead DFN Package}
APPLICATIONS
n _{RMS Power Measurement}
n _{RF Power Control}
n _{Receive and Transmit Gain Control}
n _{W-CDMA, CDMA2000, TD-SCDMA, WiMAX}
n _{RF Instrumentation}
LT5570
Fast Responding, 40MHz
to 2.7GHz Mean-Squared
Power Detector
DESCRIPTION
The LT^®5570 is a 40MHz to 2.7GHz monolithic Logarithmic
Mean-Squared RF power detector. It is capable of RMS
measurement of an AC signal with wide dynamic range,
from –52dBm to 13dBm depending on frequency. The
power of the AC signal in an equivalent decibel-scaled
value is precisely converted into DC voltage on a linear
scale, independent of the crest factor of the waveforms. The
LT5570 is suitable for precision RF power measurement and
level control for a wide variety of RF standards, including
CDMA, W-CDMA, CDMA2000, TD-SCDMA and WiMAX.
The DC output is buffered with a low output impedance
amplifier capable of driving a high capacitance load.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Protected by U.S. Patents including 7262661, 7259620, 7268608.
TYPICAL APPLICATION
40MHz to 2.7GHz Mean-Squared Power Detector
Output Voltage, Linearity Error vs Input Power, 25°C (2140 MHz)
1MF
1nF
2.4
3
5V
22nF
2.0
2
RF
INPUT
1:4
1
V_CC
2 _IN+
NC ³ DEC
4 _IN–
5
GND
LT5570
FLTR ¹⁰
EN ⁹
DNC ⁸
7
DNC
6
OUT
ENABLE
V_OUT
5570 TA01a
1.6
1
1.2
0
0.8
–1
0.4
0
–45
–35 –25 –15
CW
–2
4CH WCDMA
3CH CDMA2000
–3
–5 5 15
RF INPUT POWER (dBm)
5570 TA01b
5570f
1