AD6650BBC Analog Devices Inc, AD6650BBC Datasheet - Page 14

• Manufacturer Part Number: AD6650BBC
• Manufacturer: Analog Devices Inc

Specifications of AD6650BBC

• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Operating Supply Voltage (typ): 3.3V
• Lead Free Status / Rohs Status: Not Compliant

AD6650
TERMINOLOGY
Analog Bandwidth
The analog input frequency at which the spectral power of the
fundamental frequency (as determined by the FFT analysis) is
reduced by 3 dB.
Noise Figure (NF)
The degradation in SNR performance (in dB) of an IF input
signal after it passes through a component or system.
The AD6650 noise figure is determined by the equation
where:
k is the Boltzmann constant = 1.38 × 10
T is the temperature in kelvin.
B is the channel bandwidth in hertz (200 kHz typical).
V
Z
SNR
with a small input signal and the AD6650 in maximum gain.
Input Second-Order Intercept (IIP2)
A figure of merit used to determine a component’s or system’s
susceptibility to intermodulation distortion (IMD) from its
second-order nonlinearities. Two unmodulated carriers at a
specified frequency relationship (f1 and f2) are injected into a
nonlinear system exhibiting second-order nonlinearities
producing IMD components at f1 − f2 and f2 − f1. IIP2
graphically represents the extrapolated intersection of the
carrier’s input power with the second-order IMD component
when plotted in decibels.
Input Third-Order Intercept (IIP3)
A figure of merit used to determine a component’s or system’s
susceptibility to intermodulation distortion (IMD) from its
third-order nonlinearities. Two unmodulated carriers at a
specified frequency relationship (f1 and f2) are injected into a
nonlinear system exhibiting third-order nonlinearities
producing IMD components at (2 × f1) – f2 and (2 × f2) – f1.
IIP3 graphically represents the extrapolated intersection of the
carrier’s input power with the third-order IMD component
when plotted in decibels.
in
2
rms
is the input impedance.
FS
is the full-scale input voltage.
NF
is the computed signal-to-noise ratio referred to full scale
=
⎛
⎜
⎜
⎝
10
log
⎛
⎜
⎜
⎝
V
2
. 0
rms
001
Z
in
⎞
⎟
⎟
⎠
−
SNR
FS
−23
⎞
⎟
⎟
⎠
.
−
10
log
⎛
⎜
⎝
. 0
kTB
001
⎞
⎟
⎠
Rev. A | Page 14 of 44
(1)
Image
The AD6650 incorporates a quadrature demodulator that mixes
the IF frequency to a baseband frequency. The phase and amplitude
imbalance of this quadrature demodulator is observed in a complex
FFT as an image of the fundamental frequency. The term image
arises from the mirror-like symmetry of signal and image
frequencies about the beating-oscillator frequency (in this
case, this is dc).
Differential Analog Input Resistance, Differential Analog
Input Capacitance, and Differential Analog Input Impedance
The real and complex impedances measured at each analog
input port. The resistance is measured statically, and the
capacitance and differential input impedances are measured
with a network analyzer.
Differential Analog Input Voltage Range
The peak-to-peak differential voltage that must be applied to
the converter to generate a full-scale response. Peak differential
voltage is computed by observing the voltage on a single pin
and subtracting the voltage from the other pin, which is 180°
out of phase. The peak-to-peak differential voltage is computed
by rotating the phases of the inputs 180° and taking the peak
measurement again. Then the difference is computed between
both peak measurements.
Full-Scale Input Power
Expressed in dBm. It is computed using the following equation:
where Z
Noise
The noise, including both thermal and quantization noise, for
any range within the ADC is computed as
where:
Z is the input impedance.
FS
SNR
Signal
below full scale.
dBm
dBc
V
Power
is the full scale of the device for the frequency in question.
dBFS
noise
is the value for the particular input level.
Input
is the signal level within the ADC reported in decibels
=
Full
is the input impedance.
scale
Z
×
=
. 0
10
001
log
×
10
⎛
⎜
⎜
⎜
⎜
⎜
⎝
V
⎛
⎜ ⎜
⎝
FS
2
Full
Z
. 0
dBm
Input
001
scale
−
SNR
rms
dBc
10
⎞
⎟
⎟
⎟
⎟
⎟
⎠
−
Signal
dBFS
⎞
⎟ ⎟
⎠
(2)
(3)