AD7739 Analog Devices, AD7739 Datasheet - Page 19

• Manufacturer Part Number: AD7739
• Description: 8-Channel, 4 kHz, 24-Bit Sigma-Delta A/D Converter
• Manufacturer: Analog Devices

Specifications of AD7739

• Resolution (bits): 24bit
• # Chan: 8
• Sample Rate: 3.05MSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Bip,Diff-Uni,SE-Bip,SE-Uni
• Ain Range: Bip 0.625,Bip 1.25,Bip 2.5V,Uni 0.625,Uni 1.25,Uni 2.5V
• Adc Architecture: Sigma-Delta
• Pkg Type: SOP

CHANNEL SETUP REGISTERS
8 Bits, Read/Write Registers, Address 0x28–0x2F, Default Value 0x00
These registers are used to configure the selected channel, to configure its input voltage range, and to set up the corresponding channel
status register.
Bit
Mnemonic
Default
Bit
7
6–5
4
3
2–0
Mnemonic
BUFOFF
COM1, COM0
Stat OPT
ENABLE
RNG2–RNG0
Bit 7
BUFOFF
0
Description
Buffer Off. If reset to 0, then the internal buffer is enabled.
Operation only with the internal buffer enabled is recommended.
Analog inputs configuration:
Status Option. When this bit is set to 1, the P0 and P1 bits in the channel status register will reflect the state of
the P0 and P1 pins. When this bit is reset to 0, the RDY bit in the channel status register will reflect the channel
corresponding to the RDY bit in the ADC status register.
Channel Enable. Set this bit to 1 to enable the channel in the continuous conversion mode. A single
conversion will take place regardless of this bit’s value.
This is the channel input voltage range:
Channel
0
1
2
3
4
5
6
7
RNG2
1
1
0
0
0
0
COM1
0
AIN0–AINCOM
AIN1–AINCOM
AIN2–AINCOM
AIN3–AINCOM
AIN4–AINCOM
AIN5–AINCOM
AIN6–AINCOM
AIN7–AINCOM
RNG1
0
0
0
0
1
1
Bit 6
COM1
0
COM0
0
RNG0
0
1
0
1
0
1
Bit 5
COM0
0
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Stat OPT
COM1
1
AIN0–AIN1
AIN2–AIN3
AIN4–AIN5
AIN6–AIN7
AIN0–AIN1
AIN2–AIN3
AIN4–AIN5
AIN6–AIN7
Bit 4
0
Nominal Input Voltage Range
±2.5 V
+2.5 V
±1.25 V
+1.25 V
±0.625 V
+0.625 V
COM0
1
Bit 3
ENABLE
0
Bit 2
RNG2
0
Bit 1
RNG1
0
AD7739
Bit 0
RNG0
0