LTC1608 LINER [Linear Technology], LTC1608 Datasheet - Page 17

• Manufacturer Part Number: LTC1608
• Description: High Speed, 16-Bit, 500ksps Sampling A/D Converter with Shutdown
• Manufacturer: LINER [Linear Technology]

APPLICATIO S I FOR ATIO
Figure 17d. Suggested Evaluation Circuit Board. Inner Layer 1
Showing Separate Analog and Digital Ground Planes
ANALOG GROUND PLANE
Figure 17b. Suggested Evaluation Circuit Board.
Component Side Silkscreen and Signal Traces
Figure 18. Histogram for 4096 Conversions
2500
2000
1500
1000
500
0
–5 –4 –3 –2 –1 0
U
U
CODE
1
2
W
3
DIGITAL GROUND PLANE
4
1608 F18
5
U
noise at the rated throughput. By applying a low distortion
sine wave and analyzing the digital output using an FFT
algorithm, the ADC’s spectral content can be examined for
frequencies outside the fundamental. Figures 19a and 19b
show typical LTC1608 FFT plots.
Signal-to-Noise Ratio
The signal-to-noise plus distortion ratio [S/(N + D)] is the
ratio between the RMS amplitude of the fundamental
input frequency to the RMS amplitude of all other fre-
quency components at the A/D output. The output is band
limited to frequencies from above DC and below half the
sampling frequency. Figure 19a shows a typical spectral
content with a 500kHz sampling rate and a 3kHz input.
Figure 17e. Suggested Evaluation Circuit Board. Inner Layer 2
Showing Separate Analog and Digital Ground Planes
Figure 17c. Suggested Evaluation Circuit Board.
Bottom Side Showing Signal Traces
ANALOG GROUND PLANE
DIGITAL GROUND PLANE
LTC1608
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