AD7693 Analog Devices, AD7693 Datasheet - Page 13

• Manufacturer Part Number: AD7693
• Manufacturer: Analog Devices

Specifications of AD7693

• Resolution (bits): 16bit
• # Chan: 1
• Sample Rate: 500kSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni
• Ain Range: (2Vref) p-p,Bip (Vref) x 2
• Adc Architecture: SAR
• Pkg Type: CSP,SOP

Transfer Functions
The ideal transfer characteristic for the AD7693 is shown in
Figure 26 and Table 7.
011...111
011...110
011...101
100...010
100...001
100...000
–FSR + 0.5LSB
–FSR
Figure 26. ADC Ideal Transfer Function
–FSR + 1LSB
0 TO V
V
REF
ADA4841-2
ADA4841-2
TO 0
REF
ANALOG INPUT
1
2
3
4
5
SEE REFERENCE SECTION FOR REFERENCE SELECTION.
C
SEE TABLE 8 FOR ADDITIONAL RECOMMENDED AMPLIFIERS.
OPTIONAL FILTER. SEE ANALOG INPUT SECTION.
SEE THE DIGITAL INTERFACE SECTION FOR MOST CONVENIENT INTERFACE MODE.
3
3
REF
V+
V–
V+
V–
V+
IS USUALLY A 10µF CERAMIC CAPACITOR (X5R).
+FSR – 1.5LSB
Figure 27. Typical Application Diagram with Multiple Supplies
REF
2.7nF
4
2.7nF
4
33Ω
33Ω
+FSR – 1LSB
1
10µF
2
IN+
IN–
Rev. A | Page 13 of 24
GND
REF
AD7693
VDD
Table 7. Output Codes and Ideal Input Voltages
Description
FSR − 1 LSB
Midscale + 1 LSB
Midscale
Midscale − 1 LSB
−FSR + 1 LSB
−FSR
1
2
TYPICAL CONNECTION DIAGRAM
Figure 27 shows an example of the recommended connection
diagram for the AD7693 when multiple supplies are available.
This is also the code for an overranged analog input (V
This is also the code for an underranged analog input (V
VIO
SDO
SCK
CNV
SDI
100nF
100nF
3- OR 4-WIRE INTERFACE
5V
1.8V TO VDD
Analog Input
V
+4.999847 V
+152.6 μV
0 V
−152.6 μV
−4.999847 V
−5 V
REF
= 5 V
5
IN+
Digital Output
Code (Hex)
0x7FFF
0x0001
0x0000
0xFFFF
0x8001
0x8000
− V
IN+
IN−
− V
above V
1
2
AD7693
IN−
below V
REF
− V
GND
GND
).
).