AD831AP Analog Devices Inc, AD831AP Datasheet - Page 10

• Manufacturer Part Number: AD831AP
• Description: LOW DISTORTION 500 MHZ MIXER IC
• Manufacturer: Analog Devices Inc
• Series: AD831r

Specifications of AD831AP

• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Rohs Status: RoHS non-compliant
• Rf Type: HF, VHF
• Frequency: 500MHz
• Number Of Mixers: 1
• Gain: 0dB
• Noise Figure: 14dB
• Secondary Attributes: Down Converter
• Current - Supply: 125mA
• Voltage - Supply: 4.5 V ~ 5.5 V
• Package / Case: 20-LCC (J-Lead)
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIONS
Careful component selection, circuit layout, power supply
dc coupling, and shielding are needed to minimize the AD831’s
susceptibility to interference from radio and TV stations, etc. In
bench evaluation, we recommend placing all of the components
in a shielded box and using feedthrough decoupling networks for
the supply voltage.
Circuit layout and construction are also critical, since stray capaci-
tances and lead inductances can form resonant circuits and are a
potential source of circuit peaking, oscillation, or both.
Dual-Supply Operation
Figure 9 shows the connections for dual-supply operation. Supplies
may be as low as ±4.5 V but should be no higher than ±5.5 V, due
to power dissipation.
AD831
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Figure 9. Connections for ±5 V Dual-Supply Operation Showing Impedance
Matching Network and Gain of 2 for Driving Reverse-Terminated IF Filter
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The RF input to the AD831 is shown connected by an impedance
matching network for an assumed source impedance of 50 .
TPC 15 shows the input impedance of the AD831 plotted vs.
frequency. The input circuit can be modeled as a resistance in
parallel with a capacitance. The 82 pF capacitors (C
from IFN and IFP to VP provide a low-pass filter with a cutoff
frequency of approximately 140 MHz in down-conversion appli-
cations (see the Theory of Operation section for more details).
The LO input is connected single-ended because the limiting
amplifier provides a symmetric drive to the mixer. To minimize
intermodulation distortion, connect pins OUT and VFB by the
shortest possible path. The connections shown are for unity-gain
operation.
At LO frequencies less than 100 MHz, the AD831’s LO power
may be as low as –20 dBm for satisfactory operation. Above
100 MHz, the specified LO power of –10 dBm must be used.
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REV. C