DESCRIPTIO APPLICATIO S. LTC5530 Precision 300MHz to 7GHz RF Detector with Shutdown and Gain Adjustment FEATURES TYPICAL APPLICATIO

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1 Precision 3MHz to 7GHz RF Detector with Shutdown and Gain Adjustment FEATURES Temperature Compensated Internal Schottky Diode RF Detector Wide Input Frequency Range: 3MHz to 7GHz* Wide Input Power Range: 32dBm to dbm Buffered Detector Output with External Gain Control Low Starting Voltage: 2mV ±35mV for Gain = 2X Wide V CC Range of 2.7V to 6V Low Operating Current: 5µA Low Shutdown Current: <2µA Available in a Low Profile (mm) SOT-23 Package APPLICATIO S U 82.a, 82.b, 82.g, 82.5, 82.6 Multimode Mobile Phone Products Optical Data Links Wireless Data Modems Wireless and Cable Infrastructure RF Power Alarm Envelope Detector DESCRIPTIO U The LTC 553 is an RF power detector for RF applications operating in the 3MHz to 7GHz range. A temperature compensated Schottky diode peak detector and buffer amplifier are combined in a small ThinSOT TM package. The supply voltage range is optimized for operation from a single lithium-ion cell or 3xNiMH. The RF input voltage is peak detected using an on-chip Schottky diode. The detected voltage is buffered and supplied to the V OUT pin. The output buffer gain is set via external resistors. A power saving shutdown mode reduces current to less than 2µA. The LTC553 operates with input power levels from 32dBm to dbm., LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. *Higher frequency operation is achievable with reduced performance. Consult factory for more information. TYPICAL APPLICATIO RF INPUT U 3MHz to 7GHz RF Power Detector 33pF LTC553 V 6 RF IN CC 2 GND 3 DISABLE ENABLE SHDN V OUT V M 553 TA 5 4 R A R B pf VCC.µF Output Voltage vs RF Input Power 3MHz MHz 2MHz 3MHz 4MHz 5MHz 6MHz 7MHz TA2

2 ABSOLUTE AXI U RATI GS (Note ) W W W V CC, V OUT, SHDN, V M....3V to 6.5V RF IN Voltage...(V CC ±.5V) to 7V RF IN Power (RMS)... 2dBm I VOUT... 5mA Operating Temperature Range (Note 2).. 4 C to 85 C Maximum Junction Temperature C Storage Temperature Range C to 5 C Lead Temperature (Soldering, sec)... 3 C U U U W PACKAGE/ORDER I FOR ATIO RF IN GND 2 SHDN 3 TOP VIEW 6 V CC 5 V OUT 4 V M S6 PACKAGE 6-LEAD PLASTIC TSOT-23 T JMAX = 25 C, θ JA = 25 C/W ORDER PART NUMBER LTC553ES6 S6 PART MARKING LBDX Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at., SHDN = V CC = HI, SHDN = V = LO, RF Input Signal is Off, R A = R B = k, SHDN = HI unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS V CC Operating Voltage V I VCC Operating Current I VOUT = ma.5.7 ma I VCC Shutdown Current SHDN = LO. 2 µa V OUT (No RF Input) R LOAD = 2k 85 to 4 55 mv SHDN = LO mv V OUT Output Current V OUT =.75V, V CC = 2.7V, V OUT < mv 2 4 ma V OUT Enable Time SHDN = LO to HI, C LOAD = 33pF, R LOAD = 2k 8 2 µs V OUT Bandwidth C LOAD = 33pF, R LOAD = 2k (Note 4) 2 MHz V OUT Load Capacitance (Notes 6, 7) 33 pf V OUT Slew Rate V RFIN = V Step, C LOAD = 33pF, R LOAD = 2k (Note 3) 3 V/µs V OUT Noise V CC = 3V, Noise BW =.5MHz, 5Ω RF Input Termination mv P-P V M Voltage Range V CC.8V V V M Input Current.5.5 µa SHDN Voltage LO, Chip Disabled V CC = 2.7V to 6V.35 V SHDN Voltage HI, Chip Enabled V CC = 2.7V to 6V.4 V SHDN Input Current SHDN = 3.6V µa RF IN Input Frequency Range (Note 8) 3 to 7 MHz RF IN Input Power Range RF Frequency = 3MHz to 7GHz (Note 5, 6) V CC = 2.7V to 6V 32 to dbm RF IN AC Input Resistance F = MHz, Pin = 25dBm 22 Ω RF IN Input Shunt Capacitance F = MHz, Pin = 25dBm.65 pf Note : Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Specifications over the 4 C to 85 C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: The rise time at V OUT is measured between.3v and 2.3V. Note 4: Bandwidth is calculated based on the % to 9% rise time 2 equation: BW =.35/rise time. Note 5: RF performance is tested at MHz Note 6: Guaranteed by design. Note 7: Capacitive loading greater than this value may result in circuit instability. Note 8: Higher frequency operation is achievable with reduced performance. Consult factory for more information.

3 TYPICAL PERFOR A CE CHARACTERISTICS UW VOUT OUTPUT VOLTAGE (mv) Output Voltage vs Supply Voltage (RF Input Signal Off) SUPPLY CURRENT (µa) Supply Current vs Supply Voltage (RF Input Signal Off) VOUT OUTPUT VOLTAGE (mv) V OUT vs RF Input Power and V CC MHz V CC = 6V V CC = 5V V CC = 4V V CC = 3V SUPPLY VOLTAGE V CC (V) SUPPLY VOLTAGE V CC (V) G 553 G2 553 G MHz GAIN = G4 VOUT OUTPUT VOLTAGE (mv) MHz GAIN = G5 VOUT OUTPUT VOLTAGE (mv) MHz G6 36 3MHz 36 4MHz 36 5MHz G G G9 3

4 TYPICAL PERFOR A CE CHARACTERISTICS U W 36 6MHz 36 7MHz G G MHz GAIN = MHz GAIN = G G3 4

5 TYPICAL PERFOR A CE CHARACTERISTICS U W 3MHz MHz 2MHz V OUT SLOPE (mv/db) VOUT SLOPE (mv/db) VOUT SLOPE (mv/db) G4 553 G5 553 G6 3MHz 4MHz 5MHz VOUT SLOPE (mv/db) VOUT SLOPE (mv/db) VOUT SLOPE (mv/db) G7 553 G8 553 G9 6MHz 7MHz VOUT SLOPE (mv/db) V OUT SLOPE (mv/db) G2 553 G2 5

6 TYPICAL PERFOR A CE CHARACTERISTICS UW RF IN Input Impedance (Pin = dbm,, ) FREQUENCY RESISTANCE REACTANCE (GHz) (Ω) (Ω) S Forward Reflection Impedance.3GHz-7.GHz 553 TA3 558 TA3 6

7 TYPICAL PERFOR A CE CHARACTERISTICS U W RF IN Input Impedance (Pin = 25dBm,, ) FREQUENCY RESISTANCE REACTANCE (GHz) (Ω) (Ω) S Forward Reflection Impedance.3GHz-7.GHz 553 TA4 558 TA4 7

8 PI FU CTIO S U U U RF IN (Pin ): RF Input Voltage. Referenced to V CC. A coupling capacitor must be used to connect to the RF signal source. The frequency range is 3MHz to 7GHz. This pin has an internal 5Ω termination, an internal Schottky diode detector and a peak detector capacitor. GND (Pin 2): Ground. SHDN (Pin 3): Shutdown Input. A logic low on the SHDN pin places the part in shutdown mode. A logic high enables the part. SHDN has an internal 6k pulldown resistor to ensure that the part is in shutdown when no input is applied. In shutdown V OUT is connected to ground via a 28Ω resistor. V M (Pin 4): Negative Input to Buffer Amplifier. V OUT (Pin 5): Detector Output. V CC (Pin 6): Power Supply Voltage, 2.7V to 6V. V CC should be bypassed appropriately with ceramic capacitors. BLOCK DIAGRA W RF SOURCE V CC 6 BIAS SHUTDOWN RF IN 5Ω 5Ω + SD BUFFER 5 V OUT 3k 25pF 24k + RF DET SD 5µA 5µA 4k SD 8Ω Ω 4 V M GND 2 6k 3 SHDN 553 BD 8

9 APPLICATIO S I FOR Operation ATIO U W U U The LTC553 RF detector integrates several functions to provide RF power detection over frequencies ranging from 3MHz to 7GHz. These functions include an internal frequency compensated buffer amplifier, an RF Schottky diode peak detector and level shift amplifier to convert the RF input signal to DC and a delay circuit to avoid voltage transients at V OUT when powering up. The LTC553 has both shutdown and gain setting capabilities. Buffer Amplifier The output buffer amplifier is capable of supplying typically 4mA into a load. The negative terminal V M is brought out to a pin for gain selection. External resistors connected between V OUT and V M (R A ) and V M to ground (R B ) will set the amplifier gain. GAIN = + R R A B The amplifier is unity gain stable; however a minimum gain of two is recommended to improve low output voltage accuracy. The amplifier bandwidth is 2MHz for a gain of 2. For increased gain applications, the bandwidth is reduced according to the formula: 4MHz RB BANDWIDTH = = 4MHz ( GAIN) ( R + R ) A capacitor can be placed across the feedback resistor RA to shape the frequency response. In addition the amplifier can be used as a comparator. V M can be connected to a reference voltage. When the internal detector voltage (which is connected to the positive input of the buffer amplifier) exceeds the external voltage of V M, V OUT will switch high. RF Detector The internal RF Schottky diode peak detector and level shift amplifier converts the RF input signal to a low frequency signal. The detector demonstrates excellent efficiency and linearity over a wide range of input power. The Schottky diode is biased at about 55µA and drives a 25pF internal peak detector capacitor. Shutdown The part is in shutdown mode when SHDN is low. The supply current is reduced to < 2µA and V OUT is shorted to ground via a 28Ω resistor. When SHDN is asserted high, the part is enabled after about 8µs. A B Demo Board Schematic RF IN C4 LTC553ES6 39pF RF IN V CC 6 C2 pf V CC 2.7V TO 6V C.µF V CC SHDN R (OPT) R2 22k 2 3 GND V OUT SHDN V M 5 4 R3 k R4 k V OUT C3 (OPT) 553 DB 9

10 APPLICATIO S I FOR ATIO Applications U W U U The LTC553 can be used as a self-standing signal strength measuring receiver for a wide range of input signals from 32dBm to dbm for frequencies from 3MHz to 7GHz. Operation at higher frequencies is achievable. Consult factory for more information. The LTC553 can be used as a demodulator for AM and ASK modulated signals with data rates up to 2MHz. Depending on specific application needs, the RSSI output can be split between two branches, providing AC-coupled data (or audio) output and DC-coupled RSSI output for signal strength measurements and AGC. The LTC553 can be used for RF power detection and control. Figure is an example of transmitter power control, using the LTC553 with a capacitive tap to the power amplifier. A.5pF capacitor (C) followed by a 2Ω resistor (R) forms a coupling circuit with about 2dB loss at 9MHz referenced to the LTC553 RF input pin. In the actual product implementation, component values for the capacitive tap may be different depending on parts placement, PCB parasitics and parameters of the antenna. LTC553ES6 RF IN V CC 6.µF Li-Ion Tx PA MODULE CELL BAND R 2Ω % C.5pF ±.5pF DIPLEXER 2 GND V OUT 5 DISABLE ENABLE 3 SHDN V M 4 R2 PCS BAND R3 MOBILE PHONE DSP VPC BSE 553 F Figure. Mobile Phone Tx Power Control Application with a Capacitive Tap

11 PACKAGE DESCRIPTIO U S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # ).62 MAX.95 REF 2.9 BSC (NOTE 4).22 REF 3.85 MAX 2.62 REF.4 MIN 2.8 BSC.5.75 (NOTE 4) PIN ONE ID RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR.95 BSC PLCS (NOTE 3) BSC DATUM A. MAX REF BSC (NOTE 3) S6 TSOT NOTE:. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED.254mm 6. JEDEC PACKAGE REFERENCE IS MO-93 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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

12 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS Infrastructure LT55 High Linearity Upconverting Mixer RF Output to 3GHz, 7dBm IIP3, Integrated LO Buffer LT552 DC-3GHz High Signal Level Downconverting Mixer DC to 3GHz, 2dBm IIP3, Integrated LO Buffer LT555.5GHz to 2.5GHz Direct Conversion Quadrature Demodulator 2dBm IIP3, Integrated LO Quadrature Generator LT556.8GHz to.5ghz Direct Conversion Quadrature Demodulator 2.5dBm IIP3, Integrated LO Quadrature Generator LT557 4MHz to 9MHz Direct Conversion Quadrature Demodulator 2dBm IIP3, Integrated LO Quadrature Generator LT559.7GHz to.4ghz High Linearity Upconverting Mixer 7.dBm IIP3, 5Ω Single Ended RF and LO Ports LT552.3GHz to 2.3GHz High Linearity Upconverting Mixer 5.9dBm IIP3, 5Ω Single Ended RF and LO Ports LT5522 6MHz to 2.7GHz High Linearity Downconverting Mixer 4.5V to 5.25V Supply, 25dBm IIP3 at 9MHz, NF = 2.5dB, 5Ω Single-Ended RF and LO Ports RF Power Detectors LT554 MHz to 2.7GHz RF Measuring Receiver 8dB Dynamic Range, Temperature Compensated, 2.7V to 5.25V Supply LTC 555 3MHz to 3GHz RF Power Detectors LTC555-: 28dBm to 8dBm Range, LTC555-2: 32dBm to 2dBm Range, Temperature Compensated, 2.7V to 6V Supply LTC557 khz to MHz RF Power Detector 34dBm to 4dBm Range, Temperature Compensated, 2.7V to 6V Supply LTC558 3MHz to 7GHz RF Power Detector 32dBm to 2dBm Range, Temperature Compensated, SC7 Package LTC559 3MHz to 3GHz RF Power Detector 36dB Dynamic Range, Temperature Compensated, SC7 Package LTC553 3MHz to 7GHz Precision RF Power Detector Precision V OUT Offset Control and Shutdown LTC5532 3MHz to 7GHz Precision RF Power Detector Precision V OUT Offset Control, Adjustable Gain and Offset RF Building Blocks LT55.8GHz to 2.7GHz Receiver Front End.8V to 5.25V Supply, Dual-Gain LNA, Mixer, LO Buffer LT552 4MHz Quadrature IF Demodulator with RSSI.8V to 5.25V Supply, 7MHz to 4MHz IF, 84dB Limiting Gain, 9dB RSSI Range LT553.2GHz to 2.7GHz Direct IQ Modulator and.8v to 5.25V Supply, Four-Step RF Power Control, Upconverting Mixer 2MHz Modulation Bandwidth LT556 5MHz Quadrature IF Demodulator with VGA.8V to 5.25V Supply, 4MHz to 5MHz IF, 4dB to 57dB Linear Power Gain, 8.8MHz Baseband Bandwidth LT5546 5MHz Ouadrature IF Demodulator with 7MHz Baseband Bandwidth, 4MHz to 5MHz IF,.8V to 5.25V VGA and 7MHz Baseband Bandwidth Supply, 7dB to 56dB Linear Power Gain RF Power Controllers LTC757A RF Power Controller Multiband GSM/DCS/GPRS Mobile Phones LTC758 RF Power Controller Multiband GSM/DCS/GPRS Mobile Phones LTC957 RF Power Controller Multiband GSM/DCS/GPRS Mobile Phones LTC44 SOT-23 RF PA Controller Multiband GSM/DCS/GPRS Phones, 45dB Dynamic Range, 45kHz Loop BW LTC44 SOT-23 RF PA Controller Multiband GSM/DCS/GPRS Phones, 45dB Dynamic Range, 25kHz Loop BW LTC443 RF Power Controller for EDGE/TDMA Multiband GSM/GPRS/EDGE Mobile Phones, 25kHz Loop BW 2 Linear Technology Corporation 63 McCarthy Blvd., Milpitas, CA LT/TP 34 K PRINTED IN USA (48) FAX: (48) LINEAR TECHNOLOGY CORPORATION 24

DESCRIPTIO APPLICATIO S. LTC5531 Precision 300MHz to 7GHz RF Detector with Shutdown and Offset Adjustment FEATURES TYPICAL APPLICATIO

DESCRIPTIO APPLICATIO S. LTC5531 Precision 300MHz to 7GHz RF Detector with Shutdown and Offset Adjustment FEATURES TYPICAL APPLICATIO LTC553 Precision 3MHz to 7GHz RF Detector with Shutdown and Offset Adjustment FEATURES Temperature Compensated Internal Schottky Diode RF Detector Wide Input Frequency Range: 3MHz to 7GHz* Wide Input Power