AD8307-EB Analog Devices Inc, AD8307-EB Datasheet
AD8307-EB
Specifications of AD8307-EB
AD8307-EB Summary of contents
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... COMPENSATION LOOP Figure 1. only slightly at 500 MHz. There is no minimum frequency limit. The AD8307 can be used at audio frequencies lower. The output is a voltage scaled 25 mV/dB, generated by a current of nominally 2 μA/dB through an internal 12.5 kΩ resistor. This voltage varies from 0. input of −74 dBm (that is, the ac intercept is at − ...
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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 ............................. 5 Typical Performance Characteristics ............................................. 6 Log Amp Theory .............................................................................. 9 Progressive Compression .......................................................... 10 Demodulating Log Amps .......................................................... 11 Intercept Calibration .................................................................. 12 Offset Control ............................................................................. 12 Extension of Range ..................................................................... 13 Interfaces .......................................................................................... 14 REVISION HISTORY 7/08— ...
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... 500 500 10 900 14.3 3.2 −0.3 +1 500 0.8 1.1 1 2.7 5 150 750 AD8307 Unit mV/dB mV/dB μV dBm dBm nV/√Hz dBm kΩ MHz Hz MHz dB V − μV μV/°C kΩ pF μ μA ...
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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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... DC resistance from INP to INM = 1.1 kΩ. INM INP 1 8 VPS COM 2 7 AD8307 OFS ENB 3 TOP VIEW 6 (Not to Scale) INT OUT 4 5 Figure 2. Pin Configuration /2. POS = 12.5 kΩ. OUT /2. Due to the symmetrical nature of the response, there is no special POS Rev Page AD8307 ...
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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 1.2 1.3 1.4 1.5 1.6 V (V) ENB Figure 4. Supply Current vs INPUT FREQUENCY = 300MHz 1 0 –1 INPUT FREQUENCY = 100MHz –2 –3 –80 –60 –40 – ...
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... INPUT LEVEL (dBm) Input Driven Differentially Using Transformer 3 2 500MHz 1 0 100MHz –1 10MHz –2 –3 –70 –60 –50 –40 –30 –20 –10 0 INPUT LEVEL (dBm) Figure 14. Log Conformance vs. Input Level Supply Using AD820 as Buffer, Gain = +2 AD8307 100MHz ...
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... HP8112A SIGNAL PULSE MODE IN OUT PULSE GENERATOR PULSE VPS = 5.0V MODE 0.1µF 1nF INP VPS ENB INT 52.3Ω AD8307 INM COM OFS OUT TEK744A SCOPE TEK P6204 1nF FET PROBE CONNECT Figure 20. Test Setup for V Pulse Response OUT V OUT ...
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... AD8307. While Equation 1 is fundamentally correct, a simpler formula is appropriate for specifying the calibration attributes of a log amp like the AD8307, which demodulates a sine wave input. LOG V IN where: ...
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... This basic topology immediately opens up the possibility of enormous gain bandwidth products. For example, the AD8307 employs six cells in its main signal path, each having a small signal gain of 14.3 dB (×5.2) and a −3 dB bandwidth of about 900 MHz. The overall gain is about 20,000 (86 dB) and ...
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... Z Preference for the A/0 style of log amp over one using A/1 cells stems from several considerations. The first is that an A/0 cell can be very simple. In the AD8307 based on a bipolar transistor differential pair, having resistive loads, R emitter current source, I voltage of E The large signal transfer function is the hyperbolic tangent (see the dashed line in Figure 25) ...
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... The intercept can likewise be specified in dBm. For the AD8307 positioned at −84 dBm, corresponding to a sine amplitude of 20 μ important to bear in mind that log amps do not respond to power, but to the voltage applied to their input ...
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... With care in design, the extension to the dynamic range can be seamless over the full frequency range. For the AD8307, it amounts to a further 27 dB. Therefore, the total dynamic range is theoretically 113 dB. The specified range (−74 dBm to +16 dBm) is for high ...
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... Pin 6 is taken under worst-case conditions. Left unconnected voltage below 1 V, the AD8307 is disabled and consumes a sleep current of under 50 μA; tied to the supply voltage above fully enabled. The internal bias circuitry is very fast, typically < ...
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... 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 is 10 dBm (sine amplitude of ±1 V) when operating from supply; 16 dBm can be handled using supply. The full 16 dBm can be achieved for supplies down to 2 ...
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... Note that while the AD8307 can operate down to supply voltages of 2.7 V, the output voltage limit is reduced when the supply drops below 4 V. This characteristic is the result of necessary headroom requirements, approximately two V design of the output stage ...
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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 this very broad frequency range that find their way to the input terminals important to remember that these are ...
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... Figure 35. High Frequency Input Matching Network GAIN INPUT 100 110 120 130 FREQUENCY (MHz) Figure 36. Response of 100 MHz Matching Network ) of nominally 50 Ω and 100 Ω. IN that is not exact. The full AD8307 IN L (nH) Voltage Gain (dB) M 3300 13.3 1600 13.4 680 13.4 330 13.4 220 13 ...
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... The log intercept is adjustable over a ±3 dB range, which is sufficient to absorb the worst-case intercept error in the AD8307, plus some system level errors. For greater range, set R VR2 is adjusted while applying an accurately known CW signal near the lower end of the dynamic range to minimize the effect of any residual uncertainty in the slope ...
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... The residual ripple (±0.02 dB) when the input to the AD8307 Hz. This filter can easily be adapted to other frequencies by proportional scaling (for example, for 100 kHz use 100 pF). Placed ahead of a digital ...
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... If the gain control voltage for the X-AMP is derived from the output of the AD8307, the effect is to raise the gain of this front- end stage when the signal is small and lower it when it is large, but without altering the fundamental logarithmic nature of the response ...
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... HF short circuit at the input. This significantly lowers the –1 wideband noise; the noise reduction is about 2 dB compared to when the AD8307 is driven from a 50 Ω source. Ensure that the –2 output is free of postdemodulation ripple by lowering the low-pass filter time constant, which is provided by C5. With the value shown in Figure 44, the output time constant is 125 ms. – ...
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... Narrow Body (R-8) Dimensions shown in millimeters and (inches) Rev Page 0.325 (8.26) 0.310 (7.87) 0.300 (7.62) 0.195 (4.95) 0.130 (3.30) 0.115 (2.92) 0.014 (0.36) 0.010 (0.25) 0.008 (0.20) 0.430 (10.92) MAX 0.50 (0.0196) 45° 0.25 (0.0099) 1.27 (0.0500) 0.40 (0.0157) AD8307 ...
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... 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 AD8307ARZ-RL7 1 −40°C to +85° RoHS Compliant Part. ©1997–2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners ...