AD7685 Analog Devices, AD7685 Datasheet - Page 10

• Manufacturer Part Number: AD7685
• Manufacturer: Analog Devices

Specifications of AD7685

• Resolution (bits): 16bit
• # Chan: 1
• Sample Rate: 250kSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni
• Ain Range: (Vref) p-p
• Adc Architecture: SAR
• Pkg Type: CSP,SOP

AD7685
TYPICAL PERFORMANCE CHARACTERISTICS
250000
200000
150000
100000
50000
–100
–120
–140
–160
–180
–0.5
–1.0
–1.5
–2.0
–20
–40
–60
–80
2.0
1.5
1.0
0.5
0
0
0
0
0
80E5 80E6 80E7 80E8 80E9
Figure 8. Histogram of a DC Input at the Code Center
0
20
Figure 7. Integral Nonlinearity vs. Code
0
16384
12
40
FREQUENCY (kHz)
Figure 9. FFT Plot
29041
CODE IN HEX
32768
CODE
204292
60
8192 POINT FFT
VDD = REF = 5V
f
f
SNR = 93.3dB
THD = –111.6dB
SFDR = –113.7dB
SECOND HARMONIC = –113.7dB
THIRD HARMONIC = –117.6dB
S
IN
= 250kSPS
= 20.45kHz
POSITIVE INL = +0.33LSB
NEGATIVE INL = –0.50LSB
27755
80EA 80EB 80EC 80ED
80
49152
20
VDD = REF = 5V
100
0
120
0
65536
Rev. C | Page 10 of 28
140000
120000
100000
80000
60000
40000
20000
–100
–120
–140
–160
–180
–0.5
–1.0
–1.5
–2.0
–20
–40
–60
–80
2.0
1.5
1.0
0.5
0
0
0
0
0
804E 804F 8050 8051 8052 8053 8054 8055 8056 8057
Figure 11. Histogram of a DC Input at the Code Center
0
Figure 10. Differential Nonlinearity vs. Code
20
2
16384
213
8667
40
Figure 12. FFT Plot
FREQUENCY (kHz)
60966
CODE IN HEX
32768
CODE
125055
16384 POINT FFT
VDD = REF = 2.5V
f
f
SNR = 88.8dB
THD = –103.5dB
SFDR = –104.5dB
SECOND HARMONIC = –112.4dB
THIRD HARMONIC = –105.4dB
60
S
IN
= 250kSPS
= 20.45kHz
POSITIVE DNL = +0.21LSB
NEGATIVE DNL = –0.30LSB
59082
80
6956
49152
VDD = REF = 2.5V
179
100
0
8058
120
65536
0