AD8315 Analog Devices, AD8315 Datasheet
AD8315
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AD8315 Summary of contents
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... Single, dual, and triple band mobile handset (GSM, DCS, EDGE) Transmitter power control GENERAL DESCRIPTION The AD8315 is a complete low cost subsystem for the precise control of RF power amplifiers operating in the frequency range 0.1 GHz to 2.5 GHz and over a typical dynamic range of 50 dB. ...
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... AD8315 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ...................................................................... 12 Basic Theory................................................................................ 12 Controller-Mode Log Amps ..................................................... 13 Control Loop Dynamics............................................................ 13 REVISION HISTORY 6/06—Rev Rev. C Updated Format ...
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... Typ 0.1 −57 −44 21.5 24 −79 −70 −66 −57 2.8 0.9 0.25 0.27 0.02 2.45 2.54 V − 0.1 POS 5/200 25 = 220 pF 130 30 13 150 0.25 43.5 100 16 1 100 AD8315 Max Unit 2.5 GHz −11 dBV +2 dBm 25.5 mV/dB −64 dBV −51 dBm kΩ mA/μA nV√Hz nV/√Hz MHz V/μs ns 1.4 V dB/V kΩ V/μ POS μ ...
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... AD8315 Parameter Conditions POWER INTERFACE Pin VPOS Supply Voltage Quiescent Current ENBL high Over Temperature −30°C ≤ T Disable Current 6 ENBL low Over Temperature −30°C ≤ Operation down to 0.02 GHz is possible. 2 Mean and standard deviation specifications are available in Table 2 3 See Figure 11 for plot of input impedance vs. frequency. ...
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... Exposure to absolute maximum rating conditions for extended periods may affect POS 17 dBm device reliability. 1.6 V rms 60 mW 200°C/W 80°C/W 200°C/W 125°C −40°C to +85°C −65°C to +150°C 300°C 240°C Rev Page AD8315 ...
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... Integrator Capacitor. Connect between FLTR and COMM. 5 COMM Device Common (Ground Connection. 7 VAPC Output. Control voltage for gain control element. 8 VPOS Positive Supply Voltage: 2 5.5 V. RFIN 1 8 VPOS AD8315 ENBL 2 7 VAPC TOP VIEW VSET (Not to Scale) FLTR 4 5 COMM CONNECT Figure 2. Pin Configuration ...
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... ERROR AT +85°C AND –30°C –60 BASED ON DEVIATION FROM +85°C –30°C SLOPE AND INTERCEPT AT +25°C –70 0.1 0.3 0.5 0.7 0.9 1.1 V (V) SET AD8315 0.9GHz 1.4 1 –1 –2 –3 –4 1.3 1.5 at 1.9 GHz SET –1 – ...
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... AD8315 4 –30° –1 +85°C –2 ERROR AT +85°C AND –30°C –3 BASED ON DEVIATION FROM SLOPE AND INTERCEPT AT +25°C –4 –80 –70 –60 –50 –40 RF INPUT AMPLITUDE (dBV) (–47dBm) Figure 9. Distribution of Error at Temperature After Ambient Normalization vs. ...
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... FREQUENCY (GHz) 0.1GHz 0.9GHz 1.9GHz 2.5GHz 2.5 3.0 3.5 4.0 4.5 V (V) S Figure 19. Intercept vs. Supply Voltage C = 220 F, RF INPUT = 2GHz p FLT RF INPUT –51dBV –48dBV –33dBV –43dBV –23dBV –13dBV –53dBV AND –63dBV 100 1k 10k 100k 1M FREQUENCY (Hz) Figure 20. VAPC Noise Spectral Density AD8315 2.5 5.0 5.5 10M ...
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... HORIZONTAL DIVISION Response Time, Full-Scale Amplitude Change, Open-Loop APC 10MHz REF EXT TRIG OUTPUT SIGNAL PICOSECOND PULSE LABS PULSE PULSE MODE IN OUT GENERATOR MODE RF OUT RF –3dB 2.7V 0.1µF AD8315 RFIN VPOS 1 8 TEK P6205 VAPC 2.7V 2 ENBL 7 FET PROBE 0.3V 3 VSET NC 6 FLTR COMM NC ...
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... PULSE GENERATOR RF OUT AD811 732Ω AD8315 TEK P6205 RFIN VPOS 1 8 FET PROBE ENBL VAPC 2 7 TEK P6205 FET PROBE VSET FLTR COMM CONNECT and ENBL Grounded AD8315 TRIG OUT PULSE OUT 49.9Ω TRIG TEK TDS694C SCOPE ...
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... SLP decade, and since a decade corresponds to 20 dB, V represents the volts/dB. For the AD8315, a nominal (low frequency) slope of 24 mV/dB was chosen, and the intercept V was placed at the equivalent of −70 dBV for a sine wave input (316 μV rms). This corresponds to a power level of −57 dBm ...
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... This, in turn, is converted to a voltage (at Pin 4, FLTR, the low-pass filter capacitor node) to provide a close approximation to an exact integration of the error between the power present in the termination at the input of the AD8315 and the setpoint voltage. Finally, the voltage developed across the ground-referenced filter capacitor C special low noise amplifier of low voltage gain (× ...
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... where the coupling factor from the output of the power amplifier to the input of the AD8315 (for example, ×0.1 for coupler modified time constant (V O This is quite easy to interpret. First, it shows that a system of this sort exhibits a simple single-pole response, for any power ...
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... Using a coupling factor 0.0316 (that is, a GBC 30 dB directional coupler) and recalling that the nominal value 480 mV and V = 316 μV for the AD8315, first calculate SLP Z the range of values needed for V to control an output range of SET +33 dBm to −17 dBm. This can be found by noting that, in the ...
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... The AD8315 is typically used in the RF power control loop of a mobile handset. 2.0 2.5 A supply voltage required for the AD8315. The supply to the VPOS pin should be decoupled with a low inductance 0.1 μF surface-mount ceramic capacitor, close to the device. The AD8315 has an internal input coupling capacitor. ...
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... TRANSIENT RESPONSE The time domain response of power amplifier control loops, using any kind of controller, is only partially determined by the choice of filter, which, in the case of the AD8315, has a true integrator form 1/sT, as shown in Equation 7, with a time constant given by Equation 8. The large signal step response is also strongly dependent on the form of the gain-control law ...
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... Figure 38. Dual-Mode (GSM/DCS) PA Control Example The operational setpoint voltage, in the range 250 applied to the VSET pin of the AD8315. This is typically supplied by a DAC. The AD8315’s VAPC output drives the level control pin of the power amplifier directly. V maximum value of approximately 2 2.7 V supply while delivering the 3 mA required by the level control input of the PA ...
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... VAPC. INPUT COUPLING OPTIONS The internal 5 pF coupling capacitor of the AD8315, along with the low frequency input impedance of 2.8 kΩ, give a high-pass input corner frequency of approximately 16 MHz. This sets the minimum operating frequency. Figure 40, Figure 41, and Figure 42 show three options for input coupling ...
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... TP1, TP2 Supply and Ground Vector Pins. SW1 Device Enable. When in Position A, the ENBL pin is connected to VPOS and the AD8315 is in operating mode. In Position B, the ENBL pin is grounded putting the device in power-down mode. R1, R2 Input Interface. The 52.3 Ω resistor in Position R2 combines with the AD8315’s internal input impedance to give a broadband input impedance of around 50 Ω ...
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... PA. When used in controller mode, a capacitor must be installed in C4 for loop stability. For GSM/DCS handset power amplifiers, this capacitor should typically range from 150 pF to 300 pF. A quasimeasurement mode (where the AD8315 delivers an output voltage that is proportional to the log of the input signal) can be implemented, to establish the relationship between VSET and RFIN, by installing the two jumpers, LK1 and LK2 ...
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... AD8315 OUTLINE DIMENSIONS PIN 1 INDICATOR 1.00 0.85 0.80 SEATING 3.20 3.00 2.80 5. 3.20 4.90 3.00 4.65 2. PIN 1 0.65 BSC 0.95 0.85 1.10 MAX 0.75 0.15 0.38 0.23 0.00 0.22 0.08 COPLANARITY SEATING 0.10 PLANE COMPLIANT TO JEDEC STANDARDS MO-187-AA Figure 46. 8-Lead Mini Small Outline Package [MSOP] (RM-8) Dimensions shown in millimeters 3.25 3.00 2.75 0.60 0.45 2.25 1.95 0.30 2.00 TOP VIEW 1.75 1.75 1.55 2.95 0.50 BSC 2.75 2.55 12° MAX 0.80 MAX 0.65 TYP 0.05 MAX 0.02 NOM 0.30 0.20 REF PLANE 0.23 0.18 Figure 47. 8-Lead Lead Frame Chip Scale Package [LFCSP_VD × ...
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... AD8315ARMZ-RL −30°C to +85°C AD8315-EVAL AD8315ACP-REEL −30°C to +85°C AD8315ACP-REEL7 −30°C to +85°C 1 AD8315ACPZ-REEL −30°C to +85°C AD8315ACPZ-REEL7 1 −30°C to +85°C AD8315ACP-EVAL AD8315CSURF AD8315ACHIPS Pb-free part. Package Description Package Option 8-Lead MSOP, Tube RM-8 8-Lead MSOP, 13" ...
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... AD8315 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01520-0-6/06(C) Rev Page ...