LT5504

1

5504i

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.

However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-

tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Final Electrical Specifications

s

RSSI Measurements

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Receive AGC

s

Transmit Power Control

s

ASK and Envelope Demodulation

s

GSM/TDMA/CDMA/WCDMA

s

RF Frequency Range: 800MHz to 2.7GHz

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Ultra Wide Dynamic Range: 80dB Over Full

Frequency Range and Over Temperature

s

Wide Power Supply Range: 2.7V to 5.25V

s

Low Supply Current: 14.7mA at 3V

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Shutdown Current: 0.2

µA

s

8-Lead MS0P Package

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

800MHz to 2.7GHz

RF Measuring Receiver

January 2002

The LT

grated measuring receiver, capable of detecting a wide

dynamic range RF signal from –75dBm to +5dBm. The

logarithm of the RF signal is precisely converted into a

linear DC voltage. The LT5504 consists of RF/IF limiters,

an LO buffer amplifier, a limiting mixer, a 3rd-order

450MHz integrated low pass filter, RF/IF detectors and an

output interface. The ultrawide dynamic range is achieved

by simultaneously measuring the RF signal and a down-

converted IF signal obtained using the on-chip mixer and

an external local oscillator. The RF- and IF-detected sig-

nals are summed to generate an accurate linear DC voltage

proportional to the input RF voltage (or power) in dB. The

output is buffered with a low output impedance driver.

, LTC and LT are registered trademarks of Linear Technology Corporation.

5504 TA01a

• • •

RF+

RF–

R1

82

Ω

RF

INPUT

ENABLE

GND

LO

LO

INPUT

OUTPUT

C3

10pF

C1

100pF

R2

200

Ω

EN

3V

C2

1nF

LT5504

RF

DETECTOR

IF

DETECTOR

IF

DETECTOR

Output Voltage and Slope

Variation vs RF Input Power

PIN (dBm)

–80

2.4

2.0

1.6

1.2

0.8

0.4

0

–60

–40 –30

10

5504 TA01b

–70

–50

–20 –10

0

6

4

2

0

–2

–4

–6

AVERAGE SLOPE:23mV/dB