AD9786 Analog Devices, AD9786 Datasheet - Page 13

• Manufacturer Part Number: AD9786
• Manufacturer: Analog Devices

Specifications of AD9786

• Resolution (bits): 16bit
• Dac Update Rate: 500MSPS
• Dac Settling Time: n/a
• Max Pos Supply (v): +3.5V
• Single-supply: No
• Dac Type: Current Out
• Dac Input Format: Par

Group Delay
Number of input clocks between an impulse applied at the
device input and peak DAC output current. A half-band FIR
filter has constant group delay over its entire frequency range
Impulse Response
Response of the device to an impulse applied to the input.
Adjacent Channel Leakage Ratio (ACLR)
A ratio in dBc between the measured power within a channel
relative to its adjacent channel.
Complex Modulation
The process of passing the real and imaginary components of a
signal through a complex modulator (transfer function = e
coswt + jsinwt) and realizing real and imaginary components
on the modulator output.
jwt
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=
Hilbert Transform
A function with unity gain over all frequencies, but with a phase
shift of 90° for negative frequencies and a phase shift of –90° for
positive frequencies. Although this function cannot be imple-
mented ideally, it can be approximated with a short FIR filter
with enough accuracy to be very useful in single sideband radio
architectures.
Complex Image Rejection
In a traditional two-part upconversion, two images are created
around the second IF frequency. These images are redundant
and have the effect of wasting transmitter power and system
bandwidth. By placing the real part of a second complex modulator
in series with the first complex modulator, either the upper or
lower frequency image near the second IF can be rejected.
AD9786