AD7738BRU Analog Devices Inc, AD7738BRU Datasheet - Page 17

• Manufacturer Part Number: AD7738BRU
• Description: IC ADC 24BIT 8-CH 28-TSSOP
• Manufacturer: Analog Devices Inc

Specifications of AD7738BRU

• Rohs Status: RoHS non-compliant
• Number Of Bits: 24
• Sampling Rate (per Second): 15.4k
• Data Interface: DSP, MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 100mW
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 28-TSSOP (0.173", 4.40mm Width)
• For Use With: EVAL-AD7738EBZ - BOARD EVAL FOR AD7738

Channel Setup Registers
8 Bits, Read/Write Register, Address 28h–2Fh, Default Value 00h
These registers are used to configure the selected channel, its input voltage range, and set up the corresponding Channel Status
register.
Bit
Mnemonic
Default
Bit
7
6, 5
4
3
2–0
Channel
0
1
2
3
4
5
6
7
Channel Conversion Time Registers
8 Bits, Read/Write Register, Address 30h–37h, Default Value 91h
The Conversion Time registers enable or disable chopping and configure the digital filter for a particular channel.
This register value affects the conversion time, frequency response, and noise performance of the ADC.
Bit
Mnemonic
Default
Bit
7
6–0
REV. 0
Mnemonic
CHOP
FW
Mnemonic
BUF OFF
COM1, COM0 Analog Input Configuration. See Table XI.
Stat. Opt.
ENABLE
RNG2–0
COM1
0
AIN0–AINCOM
AIN1–AINCOM
AIN2–AINCOM
AIN3–AINCOM
AIN4–AINCOM
AIN5–AINCOM
AIN6–AINCOM
AIN7–AINCOM
Bit 7
BUF OFF
0
Description
Buffer Off. If reset to 0, then internal buffer is enabled. Only operation with internal buffer enabled
is recommended.
Status Option. When this bit is set to 1, the P1 bit in the Status Channel register will reflect the state
of the P1 pin. When this bit is reset to 0, the P1 bit in the Status Channel register bit will reflect
the channel corresponding 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 value.
The Channel Input Voltage Range. See Table XII.
Bit 7
CHOP
1
Description
Chop Enable Bit. Set to 1 to apply chopping mode for a particular channel.
CHOP = 1, Single Conversion or Continuous Conversion with one channel enabled.
Conversion Time (µs) = (FW
CHOP = 1, Continuous Conversion with two or more channels enabled.
Conversion Time (µs) = (FW
CHOP = 0, Single Conversion or Continuous Conversion with one channel enabled.
Conversion Time (µs) = (FW
CHOP = 0, Single Conversion or Continuous Conversion with two or more channels enabled.
Conversion Time (µs) = (FW
Table XI.
COM0
0
Bit 6
COM1
0
Bit 6
COM1
1
AIN0–AIN1
AIN2–AIN3
AIN4–AIN5
AIN6–AIN7
AIN0–AIN1
AIN2–AIN3
AIN4–AIN5
AIN6–AIN7
Bit 5
COM0
0
COM0
1
Bit 5
128 + 248)/MCLK Frequency (MHz), the FW in range of 2 to 127.
128 + 249)/MCLK Frequency (MHz), the FW in range of 2 to 127.
64 + 206)/MCLK Frequency (MHz), the FW in range of 3 to 127.
64 + 207)/MCLK Frequency (MHz), the FW in range of 3 to 127.
–17–
Bit 4
Stat. Opt.
0
Bit 4
RNG2
1
1
0
0
0
0
FW (7-Bit Filter Word)
RNG1
0
0
0
0
1
1
Bit 3
ENABLE
0
Bit 3
11h
Table XII.
RNG0
0
1
0
1
0
1
Bit 2
RNG2
0
Bit 2
Nominal Input
Voltage Range
± 2.5 V
0 V to +2.5 V
± 1.25 V
0 V to +1.25 V
± 0.625 V
0 V to +0.625 V
Bit 1
RNG1
0
Bit 1
AD7738
Bit 0
RNG0
0
Bit 0