AD7634 Analog Devices, AD7634 Datasheet - Page 19

• Manufacturer Part Number: AD7634
• Manufacturer: Analog Devices

Specifications of AD7634

• Resolution (bits): 18bit
• # Chan: 1
• Sample Rate: 670kSPS
• Interface: Byte,Par,Ser,SPI
• Analog Input Type: Diff-Bip,Diff-Uni
• Ain Range: 10V p-p,20 V p-p,40 V p-p
• Adc Architecture: SAR
• Pkg Type: CSP,QFP

TYPICAL CONNECTION DIAGRAM
Figure 27 shows a typical connection diagram for the AD7634 using the internal reference, serial data interface, and serial configuration
port. Different circuitry from that shown in Figure 27 is optional and is discussed in the following sections.
NOTES
1. ANALOG INPUTS ARE DIFFERENTIAL (ANTIPHASE). SEE ANALOG INPUTS SECTION.
2. THE AD8021 IS RECOMMENDED. SEE DRIVER AMPLIFIER CHOICE SECTION.
3. THE CONFIGURATION SHOWN IS USING THE INTERNAL REFERENCE. SEE VOLTAGE REFERENCE INPUT/OUTPUT SECTION.
4. A 22µF CERAMIC CAPACITOR (X5R, 1206 SIZE) IS RECOMMENDED (FOR EXAMPLE, PANASONIC ECJ4YB1A226M).
5. OPTIONAL, SEE POWER SUPPLIES SECTION.
6. THE VCC AND VEE SUPPLIES SHOULD BE VCC = [VIN(MAX) + 2V] AND VEE = [VIN(MIN) – 2V] FOR BIPOLAR INPUT RANGES.
7. OPTIONAL LOW JITTER CNVST, SEE CONVERSION CONTROL SECTION.
8. A SEPARATE ANALOG AND DIGITAL GROUND PLANE IS RECOMMENDED, CONNECTED TOGETHER DIRECTLY UNDER THE ADC.
SEE VOLTAGE REFERENCE INPUT/OUTPUT SECTION.
FOR UNIPOLAR INPUT RANGES, VEE CAN BE 0V. SEE POWER SUPPLIES SECTION.
SEE LAYOUT GUIDELINES SECTION.
–7V TO –15.75V
+7V TO +15.75V
ANALOG
ANALOG
INPUT+
INPUT–
NOTE 6
SUPPLY
SUPPLY
SUPPLY (5V)
ANALOG
NOTE 1
NOTE 4
C
NOTE 2
U1
NOTE 2
U1
C
10µF
10µF
C
C
C
22µF
10µF
REF
2.7nF
2.7nF
15Ω
15Ω
Figure 27. Typical Connection Diagram Shown with Serial Interface and Serial Programmable Port
100nF
100nF
100nF
100nF
VCC
VEE
IN–
REF
REFBUFIN
REFGND
IN+
AVDD
NOTE 3
NOTE 5
AGND
10Ω
10µF
DGND
PDREF
Rev. A | Page 19 of 32
100nF
NOTE 3
AD7634
PDBUF
AGND
SUPPLY (5V)
NOTE 8
DIGITAL
DVDD
DGND
PD
OVDD
RD
100nF
MODE[1:0]
CS
D0/OB/2C
BIPOLAR
IMPULSE
SDOUT
SCCLK
HW/SW
SDCLK
CNVST
OGND
WARP
BUSY
SCCS
RESET
SCIN
TEN
10µF
33Ω
OVDD
NOTE 7
DIGITAL
INTERFACE
SUPPLY
(2.5V, 3.3V, OR 5V)
D
CLOCK
MICROPROCESSOR/
SERIAL
PORT 1
SERIAL
PORT 2
MicroConverter
DSP
AD7634
®
/