V CC 1, 4. 7dB. 7dB 6 GND

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1 9-998; Rev ; /7 EVALUATION KIT AVAILABLE.GHz to GHz, 75dB Logarithmic General Description The MAX5 complete multistage logarithmic amplifier is designed to accurately convert radio-frequency (RF) signal power in the.ghz to GHz frequency range to an equivalent DC voltage. The outstanding dynamic range and precision over temperature of this log amplifier make it particularly useful for a variety of base station and other wireless applications, including automatic gain control (AGC), transmitter power measurements, and received signal strength indication (RSSI) for terminal devices. The MAX5 can also be operated in a controller mode where it measures, compares, and controls the output power of a variable-gain amplifier as part of a fully integrated AGC loop. This logarithmic amplifier provides much wider measurement range and superior accuracy compared to controllers based on diode detectors, while achieving excellent temperature stability over the full -4 C to +85 C operating range. Applications AGC Measurement and Control RF Transmitter Power Measurement RSSI Measurements Cellular Base Station, WLAN, Microwave Link, Radar, and other Military Applications Features Complete RF.GHz to GHz Frequency Range Exceptional Accuracy Over Temperature High Dynamic Range.7V to 5.5V Supply Voltage Range* Scaling Stable Over Supply and Temperature Variations Controller Mode with Error Output Shutdown Mode with Typically µa of Supply Current Available in 8-Pin µmax and TDFN Packages *See Power-Supply Connections section. µmax is a registered trademark of Maxim Integrated Products, Inc. PART Ordering Information TEMP RANGE PWDN 5 OFFSET AND COMMON- MODE AMP kω MAX5 PIN- PACKAGE PKG CODE MAX5EUA -4 C to +85 C 8 µmax U8- MAX5EUA-T -4 C to +85 C 8 µmax U8- T = Tape-and-reel. +Denotes lead-free and RoHS compliance. *EP = Exposed paddle. Ordering Information continued at end of data sheet. Functional Diagram MAX5, 4 POWER DETECTORS INHI Σ Σ Σ 8 OUT INLO 5Ω 7dB 7dB 7dB kω 7 SET Pin Configuration appears at end of data sheet. 6 GND Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 .GHz to GHz, 75dB Logarithmic MAX5 ABSOLUTE MAXIMUM RATINGS (Pins,, 4) to GND...-.V to +5.5V SET, PWDN to GND...-.V to ( +.V) Input Power Differential INHI, INLO...+dBm Input Power Single Ended (INHI or INLO grounded)...+9dbm Continuous Power Dissipation (T A = +7 C) 8-Pin µmax (derate 4.5mW/ C above +7 C)...6mW 8-Pin TDFN (derate 8.5mW/ C above +7 C)...48mW Operating Temperature Range...-4 C to +85 C Junction Temperature...+5 C Storage Temperature Range C to +5 C Lead Temperature (soldering, s)...+ C Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS (MAX5 typical application circuit (Figure ), V S = +.V, f RF = MHz to MHz, R = Ω, R4 = Ω, R L = kω, T A = -4 C to +85 C, unless otherwise noted. Typical values are at T A = +5 C, unless otherwise noted.) (Note ) POWER SUPPLY PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V S R4 = 75Ω ±%, PWDN must be connected to GND R4 = Ω.7.6 V Supply Current I CC T A = +5 C, V S = 5.5V, R4 = 75Ω 7. T A = +5 C 7..5 ma Supply Current Variation with Temp I CC T A = -4 C to +85 C.5 ma/ C Shutdown Current I CC V PWDN = µa CONTROLLER REFERENCE (SET) SET Input Voltage Range.5 to.8 V SET Input Impedance 4 kω DETECTOR OUTPUT (OUT) Source Current 4 ma Sink Current 45 µa Minimum Output Voltage V OUT(MIN).5 V Maximum Output Voltage V OUT(MAX).8 V

3 .GHz to GHz, 75dB Logarithmic AC ELECTRICAL CHARACTERISTICS (MAX5 typical application circuit (Figure ), V S = +.V, f RF = MHz to MHz, R = Ω, R4 = Ω, R L = kω, T A = -4 C to +85 C, unless otherwise noted. Typical values are at T A = +5 C, unless otherwise noted.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS RF Input Frequency Range f RF. to GHz Return Loss S -5 db Large-Signal Response Time RSSI MODE.GHz P IN = no signal to dbm, ±.5dB settling accuracy 5 ns RF Input Power Range (Note ) -65 to +5 dbm ±db Dynamic Range T A = -4 C to +85 C (Note ) 7 db Range Center - dbm Temp Sensitivity when T A > +5 C T A = +5 C to +85 C, P IN = -5dBm +.8 db/ C MAX5 Temp Sensitivity when T A < +5 C T A = -4 C to +5 C, P IN = -5dBm -.54 db/ C Slope (Note 4) 9 mv/db Typical Slope Variation T A = -4 C to +85 C -4 µv/ C Intercept (Note 5) - dbm Typical Intercept Variation T A = -4 C to +85 C. dbm/ C RSSI MODE.9GHz RF Input Power Range (Note ) -65 to +5 dbm ±db Dynamic Range T A = -4 C to +85 C (Note ) 7 db Range Center - dbm Temp Sensitivity when T A > +5 C Temp Sensitivity when T A < +5 C T A = +5 C to +85 C, P IN = -5dBm T A = -4 C to +5 C, P IN = -5dBm ±.8 db/ C -.54 db/ C Slope (Note 4) 8. mv/db Typical Slope Variation T A = -4 C to +85 C -4 µv/ C Intercept (Note 5) -97 dbm Typical Intercept Variation T A = -4 C to +85 C. dbm/ C RSSI MODE.9GHz RF Input Power Range (Note ) -55 to +5 dbm ±db Dynamic Range T A = -4 C to +85 C (Note ) 6 db Range Center -5 dbm Temp Sensitivity when T A > +5 C Temp Sensitivity when T A < +5 C T A = +5 C to +85 C, P IN = -5dBm T A = -4 C to +5 C, P IN = -5dBm ±. db/ C -.8 db/ C Slope (Note 4) 8 mv/db Typical Slope Variation T A = -4 C to +85 C -4.8 µv/ C

4 .GHz to GHz, 75dB Logarithmic MAX5 AC ELECTRICAL CHARACTERISTICS (continued) (MAX5 typical application circuit (Figure ), V S = +.V, f RF = MHz to MHz, R = Ω, R4 = Ω, R L = kω, T A = -4 C to +85 C, unless otherwise noted. Typical values are at T A = +5 C, unless otherwise noted.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Intercept (Note 5) -8 dbm Typical Intercept Variation T A = -4 C to +85 C. dbm/ C RSSI MODE.5GHz RF Input Power Range (Note ) -45 to -5 dbm ±db Dynamic Range T A = -4 C to +85 C (Note ) 4 db Range Center -5 dbm Temp Sensitivity when T A > +5 C T A = +5 C to +85 C, P IN = -5dBm -.8 db/ C Temp Sensitivity when T A < +5 C T A = -4 C to +5 C, P IN = -5dBm -.8 db/ C Slope (Note 4) 6.8 mv/db Typical Slope Variation T A = -4 C to +85 C -8 µv/ C Intercept (Note 5) -8 dbm Typical Intercept Variation T A = -4 C to +85 C. dbm/ C Note : The MAX5 is guaranteed by design for T A = -4 C to +85 C, as specified. Note : Typical minimum and maximum range of the detector at the stated frequency. Note : Dynamic range refers to the range over which the error remains within the stated bounds. The error is calculated at -4 C and +85 C, relative to the curve at +5 C. Note 4: The slope is the variation of the output voltage per change in input power. It is calculated by fitting a root-mean-square (RMS) straight line to the data indicated by RF input power range. Note 5: The intercept is an extrapolated value that corresponds to the output power for which the output voltage is zero. It is calculated by fitting an RMS straight line to the data. 4

5 .GHz to GHz, 75dB Logarithmic Typical Operating Characteristics (MAX5 typical application circuit (Figure ), V S = =.V, P IN = -dbm, f IN = MHz, R = Ω, R4 = Ω, R L = kω, V PWDN = V, T A = +5 C, unless otherwise noted.) OUTPUT VOLTAGE (V) f IN =.GHz OUTPUT VOLTAGE.8 T A = +5 C.6 T A = -4 C MAX5 toc f IN =.GHz NORMALIZED TO DATA AT +5 C T A = +5 C T A = -4 C MAX5 toc - - =.7V f IN =.GHz, NORMALIZED TO DATA AT +5 C =.6V =.V =.V MAX5 toc MAX5 - - f IN =.GHz, T A = -4 C NORMALIZED TO DATA AT +5 C =.V =.7V =.V =.6V MAX5 toc4 OUTPUT VOLTAGE (V) f IN =.9GHz OUTPUT VOLTAGE.8 T A = +5 C.6 T A = -4 C MAX5 toc5 - - f IN =.9GHz NORMALIZED TO DATA AT +5 C T A = +5 C T A = -4 C MAX5 toc6 - =.7V f IN =.9GHz, NORMALIZED TO DATA AT +5 C =.V =.6V =.V MAX5 toc7 - f IN =.9GHz, T A = -4 C NORMALIZED TO DATA AT +5 C =.V =.V =.7V MAX5 toc8 OUTPUT VOLTAGE (V) f IN =.9GHz OUTPUT VOLTAGE MAX5 toc =.6V T A = +5 C T A = -4 C

6 .GHz to GHz, 75dB Logarithmic MAX5 Typical Operating Characteristics (continued) (MAX5 typical application circuit (Figure ), V S = =.V, P IN = -dbm, f IN = MHz, R = Ω, R4 = Ω, R L = kω, V PWDN = V, T A = +5 C, unless otherwise noted.) - - f IN =.9GHz NORMALIZED TO DATA AT +5 C T A = +5 C T A = -4 C MAX5 toc - - f IN =.9GHz, NORMALIZED TO DATA AT +5 C =.7V =.6V =.V =.V MAX5 toc - - f IN =.9GHz, T A = -4 C NORMALIZED TO DATA AT +5 C =.V =.7V =.V =.6V MAX5 toc f IN =.5GHz OUTPUT VOLTAGE MAX5 toc f IN =.5GHz NORMALIZED TO DATA AT +5 C MAX5 toc4 f IN =.5GHz, NORMALIZED TO DATA AT +5 C MAX5 toc5 OUTPUT VOLTAGE (V)..8.6 T A = +5 C T A = -4 C T A = -4 C T A = +5 C =.V =.7V VCC =.V =.6V f IN =.5GHz, T A = -4 C NORMALIZED TO DATA AT +5 C =.V =.7V =.V =.6V MAX5 toc6 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE f IN =.68GHz T A = +5 C T A = +5 C T A = -4 C MAX5 toc7 - - f IN =.68GHz NORMALIZED TO DATA AT +5 C T A = -4 C T A = +5 C MAX5 toc T A = -4 C

7 .GHz to GHz, 75dB Logarithmic Typical Operating Characteristics (continued) (MAX5 typical application circuit (Figure ), V S = =.V, P IN = -dbm, f IN = MHz, R = Ω, R4 = Ω, R L = kω, V PWDN = V, T A = +5 C, unless otherwise noted.) RF INPUT VOLTAGE, OUTPUT VOLTAGE (V) f IN = MHz RF PULSE RESPONSE V OUT RFIN (AC-COUPLED) MAX5 toc9 MAGNITUDE (db) S MAGNITUDE =.V,.6V =.7V,.V MAX5 toc MAGNITUDE (db) T A = -4 C T A = +5 C S MAGNITUDE MAX5 toc MAX5 -. TIME (5ns/div) FREQUENCY (GHz) FREQUENCY (GHz) Pin Description PIN NAME FUNCTION, 4 Supply Voltage. Bypass with capacitors as specified in the application drawing. Place capacitors as close to the pin as possible (see the Power-Supply Connections section)., INHI, INLO Differential RF Inputs 5 PWDN Power-Down Input. Drive PWDN with a logic-high to power down the IC. PWDN must be connected to GND for V S between 4.75V and 5.5V with R4 = 75Ω. 6 GND Ground. Connect to the PCB ground plane. 7 SET Set-Point Input. To operate in detector mode, connect SET to OUT. To operate in controller mode, connect a precision voltage source to control the power level of a power amplifier. 8 OUT EP Detector Output. In detector mode, this output provides a voltage proportional to the log of the input power. In controller mode, this output is connected to a power-control input on a power amplifier (PA). Exposed Paddle (TDFN package only). Connect EP to GND using multiple vias, or the EP can also be left unconnected. 7

8 .GHz to GHz, 75dB Logarithmic MAX5 Detailed Description The MAX5 is a successive detection logarithmic amplifier designed for use in RF power measurement and AGC applications with a.ghz to GHz frequency range from a single.7v to.6v power supply. It is pin compatible with other leading logarithmic amplifiers. The MAX5 provides for improved performance with a high 75dB dynamic range at MHz, and exceptional accuracy over the extended temperature range and supply voltage range. RF Input The MAX5 differential RF input (INHI, INLO) allows for broadband signals between MHz and GHz. For single-ended signals, AC-couple INLO to ground. The RF inputs are internally biased and need to be AC-coupled using 68pF capacitors as shown in Figure and Figure. An internal 5Ω resistor between INHI and INLO provides a good 5MHz to.ghz match. SET Input The SET input is used for loop control when in controller mode or to set the slope of the output signal (mv/db) when in detector mode. The internal input structure of SET is two series kω resistors connected to ground. The center node of the resistors is fed to the negative input of the internal output op amp. Power-Supply Connections The MAX5 requires power-supply bypass capacitors connected close to each pin. At each pin, connect a.µf capacitor (C4, C6) and a pf capacitor (C, C5) with the pf capacitor being closest to the pin. For power-supply voltages (V S ) between.7v and.6v, set R4 = Ω (see the typical applications circuits). For power-supply voltages (V S ) between 4.75V and 5.5V, set R4 = 75Ω ±% (ppm/ C max) and PWDN must be connected to GND. Power-Down Mode The MAX5 can be powered down by driving PWDN with logic high (logic high = ). In power-down mode, the supply current is reduced to a typical value of µa. For normal operation, drive PWDN with a logic low. It is recommended when using power-down that an RF signal not be applied before the power-down signal is low. Applications Information Detector (RSSI) Mode In detector mode, the MAX5 acts like an RSSI, which provides an output voltage proportional to the input power. This is accomplished by providing a feedback path from OUT to SET (R = Ω; see Figure ). By connecting SET directly to OUT, the op amp gain is set to V/V due to two internal kω feedback resistors. This provides a detector slope of approximately 8mV/dB with a.5v to.8v output range. Controller Mode The MAX5 can also be used as a detector/controller within an AGC loop. Figure depicts one scenario where the MAX5 is employed as the controller for a variable-gain PA. As shown in the figure, the MAX5 monitors the output of the PA through a directional coupler. An internal integrator (Figure ) compares the V S R4 C6 RFIN C4 C5 C C C 4 INHI INLO DETECTORS kω MAX5 kω OUT SET 8 7 GND 6 PWDN 5 Figure. Detector-Mode (RSSI) Typical Application Circuit Table. Suggested Components of Typical Applications Circuits DESIGNATION VALUE TYPE R OUT C, C 68pF 6 ceramic capacitors C, C5 pf 6 ceramic capacitors C4, C6.µF 6 ceramic capacitors R* Ω 6 resistor R4** Ω 6 resistor *RSSI mode only. **V S =.7V to.6v. 8

9 .GHz to GHz, 75dB Logarithmic V S R4 C6 RFIN C5 C C DETECTORS INHI INLO kω OUT SET 8 7 kω GND 6 V OUT V SET TRANSMITTER POWER AMPLIFIER SET-POINT DAC OUT SET GAIN-CONTROL INPUT kω LOGARITHMIC DETECTOR IN COUPLER MAX5 C4 C 4 MAX5 PWDN 5 kω MAX5 Figure. Controller-Mode Typical Application Circuit Figure. System Diagram for Automatic Gain-Control Loop detected signal with a reference voltage determined by V SET. The integrator, acting like a comparator, increases or decreases the voltage at OUT, according to how closely the detected signal level matches the V SET reference. The MAX5 adjusts the power of the PA to a level determined by the voltage applied to SET. With R = Ω, the controller mode slope is approximately 9mV/dB (RF = MHz). Layout Considerations As with any RF circuit, the layout of the MAX5 circuit affects the device s performance. Use an abundant number of ground vias to minimize RF coupling. Place the input capacitors (C, C) and the bypass capacitors (C C6) as close to the IC as possible. Connect the bypass capacitors to the ground plane with multiple vias. 9

10 .GHz to GHz, 75dB Logarithmic MAX5 Ordering Information (continued) PART TEMP RANGE PIN- PACKAGE PKG CODE MAX5EUA+ -4 C to +85 C 8 µmax U8- MAX5EUA+T -4 C to +85 C 8 µmax U8- MAX5ETA -4 C to +85 C 8 TDFN-EP* (mm x mm) T8- TOP VIEW INHI INLO 4 Pin Configuration 8 OUT 7 SET MAX5 6 GND 5 PWDN MAX5ETA-T -4 C to +85 C 8 TDFN-EP* (mm x mm) T8- µmax MAX5ETA+ -4 C to +85 C 8 TDFN-EP* (mm x mm) T8- TOP VIEW OUT SET GND PWDN MAX5ETA+T -4 C to +85 C 8 TDFN-EP* (mm x mm) T T = Tape-and-reel. +Denotes lead-free and RoHS compliance. *EP = Exposed paddle. MAX5 4 INHI INLO TDFN Chip Information TRANSISTOR COUNT: 57 PROCESS: BiCMOS

11 .GHz to GHz, 75dB Logarithmic Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to 8 Ø.5±. D TOP VIEW E H 4X S BOTTOM VIEW 8 DIM A A INCHES MIN MAX BSC A. b c D e E.6 H.88 L.6 α S.7 BSC MILLIMETERS MIN MAX BSC BSC 8LUMAXD.EPS MAX5 A A A e b c L α FRONT VIEW SIDE VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, 8L umax/usop APPROVAL DOCUMENT CONTROL NO. REV. -6 J

12 .GHz to GHz, 75dB Logarithmic MAX5 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to 6, 8, &L, DFN THIN.EPS PACKAGE OUTLINE, 6,8, & 4L, TDFN, EXPOSED PAD, xx.8 mm -7 H

13 .GHz to GHz, 75dB Logarithmic Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to COMMON DIMENSIONS SYMBOL MIN. MAX. A.7.8 D.9. E.9. A..5 L..4 k.5 MIN. A. REF. PACKAGE VARIATIONS PKG. CODE N D E e JEDEC SPEC b [(N/)-] x e T6-6.5±..±..95 BSC MO9 / WEEA.4±.5.9 REF T6-6.5±..±..95 BSC MO9 / WEEA.4±.5.9 REF T8- T- T ±..5±..±..7±..±..65 BSC.±.5.95 REF.±..5 BSC MO9 / WEED-.5±.5. REF.±..5 BSC MO9 / WEED-.5±.5. REF.4 BSC MO9 / WEEC T8-8.5±..±..65 BSC MO9 / WEEC.±.5.95 REF T8-8.5±..±..65 BSC MO9 / WEEC.±.5.95 REF T-.5±. T4-4.7±..± ±.5.4 REF.4 BSC ±.5.4 REF MAX5 PACKAGE OUTLINE, 6,8, & 4L, TDFN, EXPOSED PAD, xx.8 mm -DRAWING NOT TO SCALE- -7 H Revision History Pages changed at Rev :,, Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.