AD8307AN Analog Devices Inc, AD8307AN Datasheet
AD8307AN
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AD8307AN Summary of contents
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FEATURES Complete multistage logarithmic amplifier 92 dB dynamic range: –75 dBm to +17 dBm to –90 dBm using matching network Single supply of 2.7 V minimum at 7.5 mA typical DC to 500 MHz operation, ±1 dB linearity Slope of ...
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AD8307 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Absolute Maximum Ratings ............................................................ 4 ESD Caution .................................................................................. 4 Pin Configuration and Function Descriptions ...
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SPECIFICATIONS 25°C, R ≥ 1 MΩ, unless otherwise noted Table 1. Parameter GENERAL CHARACTERISTICS Input Range (±3 dB Error) Input Range (±1 dB Error) Logarithmic Conformance Logarithmic Slope vs. Temperature Logarithmic ...
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... Parameter Supply Input Voltage (Pin 1 and Pin 8) Storage Temperature Range (N, R) Ambient Temperature Range, Rated Performance Industrial, AD8307AN, AD8307AR Lead Temperature Range (Soldering, 10 sec) Stresses above those listed under Absolute Maximum Ratings can cause permanent damage to the device. This is a stress Ratings rating only ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 3. Pin Function Descriptions Pin No. Mnemonic Description 1 INM Signal Input Minus Polarity. Normally COM Common Pin (Usually Grounded). 3 OFS Offset Adjustment. External capacitor connection. 4 OUT Logarithmic (RSSI) ...
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AD8307 TYPICAL PERFORMANCE CHARACTERISTICS 1.0 1.1 1.2 1.3 1.4 1.5 1.6 V (V) ENB Figure 3. Supply Current vs 1.0 1.1 ...
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INT P = 3.0V IN 2.5 10MHz, INT = –96.52dBm 2.0 INT P = 4.0V IN 10MHz, INT = –87.71dBm 1.5 NO CONNECT ON INT 10MHz, INT = –82.90dBm 1.0 0.5 0 –80 –70 –60 –50 –40 –30 –20 ...
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AD8307 CH1 200mV GND CH2 2.00V Figure 15. Power-Up Response Time CH1 200mV V OUT ENB CH 2 GND CH2 2.00V Figure 16. Power-Down Response Time VPS = 5.0V HP8648B HP8112A 0.1µF SIGNAL PULSE GENERATOR GENERATOR 1nF ...
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LOG AMP THEORY Logarithmic amplifiers perform a more complex operation than that of classical linear amplifiers, and their circuitry is significantly different. A good grasp of what log amps do and how they work can prevent many pitfalls in their ...
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AD8307 just dB. The logarithmic function disappears from the formula because the conversion has already been implicitly performed in stating the input in decibels. This is strictly a concession to popular convention; log amps manifestly do not respond to power ...
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Further analysis shows that right up to the point where the input to the first cell is above the knee voltage, V OUT for a ratio change This can be expressed as a certain IN ...
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... INTERCEPT CALIBRATION All monolithic log amps from Analog Devices include accurate means to position the intercept voltage ,V a demodulating log amp). Using the scheme shown in Figure 26, the basic value of the intercept level departs considerably from that predicted by the simpler analyses given earlier ...
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In the AD8307, this is achieved by an on-chip filter, providing sufficient suppression of HF feedback to allow operation above 1 MHz. To extend the range below this frequency, an external capacitor can be added. This permits the high-pass corner ...
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AD8307 INTERFACES The AD8307 comprises six main amplifier/limiter stages, each having a gain of 14.3 dB and small signal bandwidth of 900 MHz; the overall gain with a −3 dB bandwidth of 500 MHz. These six cells ...
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In most applications, the signal is single sided and can be applied to either Pin 1 or Pin 8, with the other pin ac-coupled to ground. Under these conditions, the largest input signal that can be handled by the AD8307 ...
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AD8307 It can be desirable to increase the speed of the output response, with the penalty of increased ripple. One way to do this is by connecting a shunt load resistor from Pin OUT to ground, which raises the low-pass ...
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THEORY OF OPERATION The AD8307 has very high gain and a bandwidth from dc to over 1 GHz, at which frequency the gain of the main path is still over 60 dB. Consequently susceptible to all signals within ...
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AD8307 INPUT MATCHING Where higher sensitivity is required, an input matching network is valuable. Using a transformer to achieve the impedance transformation also eliminates the need for coupling capacitors, which lowers the offset voltage generated directly at the input, and ...
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SLOPE AND INTERCEPT ADJUSTMENTS Where higher calibration accuracy is needed, the adjustments shown in Figure 37 can be used, either singly or in combination. The log slope is lowered to 20 mV/dB by shunting the nominally 12.5 kΩ on-chip load ...
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AD8307 APPLICATIONS INFORMATION The AD8307 is a highly versatile and easily applied log amp requiring very few external components. Most applications of this device can be accommodated using the simple connections shown in the preceding section. BUFFERED OUTPUT The output ...
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Ω POWER METER The front-end adaptation shown in Figure 41 provides the measurement of power being delivered from a transmitter final amplifier to an antenna. The range has been set to cover the power ...
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AD8307 2.50 2.25 2.00 WITHOUT FILTER 1.75 1.50 1.25 1.00 ERROR (WITH FILTER) 0.75 0.50 WITH FILTER 0.25 0 –100 –80 –60 –40 INPUT LEVEL (dBm) Figure 43. Results for 120 dB Measurement System OPERATION AT LOW FREQUENCIES The AD8307 ...
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OUTLINE DIMENSIONS 0.210 (5.33) MAX 0.150 (3.81) 0.130 (3.30) 0.115 (2.92) 0.022 (0.56) 0.018 (0.46) 0.014 (0.36) CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN ...
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... AD8307 ORDERING GUIDE Model Temperature Range AD8307AN −40°C to +85°C 1 AD8307ANZ −40°C to +85°C AD8307AR −40°C to +85°C AD8307AR-REEL −40°C to +85°C AD8307AR-REEL7 −40°C to +85°C 1 AD8307ARZ −40°C to +85°C 1 AD8307ARZ-REEL −40°C to +85°C ...