ADA4620-2ARZ-R7 datasheet(41/49 Pages) AD

41 / 49 page

Data Sheet

ADA4620-1, ADA4620-2

analog.com

Rev. 0

41 of 49

Figure 126. Distortion and Noise Performance vs. Sample Rate for Cd = 680 pF

Figure 126 plots various distortion and noise performances achieved with various sample rates and capacitor Cd =

680 pF. Figure 127 is an example FFT.

Figure 127. 8192 Bin FFT Gathered from the Circuit at 300 kSps, −0.5 dBFS, 5.017 kHz Input Sinusoid

Multiplexer Compatibility

High-channel-density data-acquisition systems used in medical imaging, industrial process control, and automatic

test equipment require numerous ADC channels to acquire data from multiple sensors or analog voltages. This

demands significant board space, power, and cost. To address this, a multiplexing technique is employed, allowing

signals from many sensors to be routed to a smaller number of ADCs that convert each channel sequentially. This

technique reduces the downstream circuitry needed compared to a per-channel design. By using fewer ADCs per

system, multiplexing offers substantial savings in power, size, and cost. However, to effectively implement a

multiplexing solution, attention must be given to several details, especially when quickly switching between

channels, ensuring accurate measurements, and maintaining low power consumption.

In multiplexed data-acquisition (DAQ) systems, an analog multiplexer is used to time-multiplex input analog

channels because it allows multiple signals to be routed to a single ADC for conversion. Interfacing the output of

the multiplexer to a high input impedance stage before connecting it to the ADC is important because it improves

measurement accuracy and settling time. This configuration ensures that the multiplexer can switch channels

more quickly and efficiently, enhancing overall signal chain throughput.

HD2

HD3

SNR

SAMPLE RATE (kSps)

100

200

300

400

500

600

700

800

900

1000

–122

–118

–114

–110

–106

–102

–98

–94

–90

BIN #

1024

2048

3072

4096

5120

6144

7168

8192

–160

–140

–120

–100

–80

–60

–40

–20

fS = 300kSps

SNR = 101.96dB

THD = –110.63dB

BIN WIDTH = 18.311Hz

F2 AMPLITUDE = –120.7dBc

F3 AMPLITUDE = –112.3dBc

F1 AMPLITUDE = –0.5dBFS

F1 = 5.017089844kHz

ADA4620-2ARZ-R7 Folha de dados(PDF) 41 Page - Analog Devices

ADA4620-2ARZ-R7 Folha de dados(HTML) 41 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

Folha de dados Download

Ligação URL