AD7608 Analog Devices, AD7608 Datasheet - Page 13

• Manufacturer Part Number: AD7608
• Description: 8-Channel DAS with 18-Bit, Bipolar, Simultaneous Sampling ADC
• Manufacturer: Analog Devices

Specifications of AD7608

• Resolution (bits): 18bit
• # Chan: 8
• Sample Rate: 200kSPS
• Interface: Par,Ser,SPI
• Analog Input Type: Diff-Bip
• Ain Range: Bip 10V,Bip 5.0V
• Adc Architecture: SAR
• Pkg Type: QFP

Data Sheet
Pin No.
34
36, 39
42
43, 46
44, 45
49, 51, 53,
55, 57, 59,
61, 63
50, 52, 54,
56, 58, 60,
62, 64
1
Refers to classification of pin type; P denotes power, AI denotes analog input, REF denotes reference, DI denotes digital input, DO denotes digital output.
Type
DI
P
REF
REF
REF
AI
AI/
GND
1 2 F 1 1 F
1
Mnemonic
REF SELECT
REGCAP
REFIN/
REFOUT
REFGND
REFCAPA,
REFCAPB
V1 to V8
V1GND to
V8GND
Description
Internal/External Reference Selection Input. Logic input. If this pin is set to logic high then the
internal reference is selected and is enabled, if this pin is set to logic low then the internal reference
is disabled and an external reference voltage must be applied to the REFIN/REFOUT pin.
Decoupling Capacitor Pins for Voltage Output from Internal Regulator. These output pins should be
decoupled separately to AGND using a 1 μF capacitor. The voltage on these output pins is in the
range of 2.5 V to 2.7 V.
Reference Input/Reference Output. The on-chip reference of 2.5 V is available on this pin for external
use if the REF SELECT pin is set to a logic high. Alternatively, the internal reference can be disabled
by setting the REF SELECT pin to a logic low and an external reference of 2.5 V can be applied to this
input. See the Internal/External Reference section. Decoupling is required on this pin for both the
internal or external reference options. A 10 µF capacitor should be applied from this pin to ground
close to the REFGND pins.
Reference Ground Pins. These pins should be connected to AGND.
Reference Buffer Output Force/Sense Pins. These pins must be connected together and decoupled
to AGND using a low ESR 10 μF ceramic capacitor.
Analog Inputs. These pins are single-ended analog inputs. The analog input range of these channels
is determined by the RANGE pin.
Analog Input Ground Pins. These pins correspond to the V1 to V8 analog input pins. Connect all
analog input AGND pins to the AGND plane of a system.
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AD7608