AD7785BRUZ Analog Devices Inc, AD7785BRUZ Datasheet - Page 21

• Manufacturer Part Number: AD7785BRUZ
• Description: IC ADC 20BIT SIGMA-DELTA 16TSSOP
• Manufacturer: Analog Devices Inc

Specifications of AD7785BRUZ

• Data Interface: MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Bits: 20
• Sampling Rate (per Second): 470
• Number Of Converters: 1
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 16-TSSOP (0.173", 4.40mm Width)
• Resolution (bits): 20bit
• Input Channel Type: Differential
• Supply Voltage Range - Analogue: 2.7V To 5.25V
• Supply Voltage Range - Digital: 2.7V To 5.25V
• Supply: RoHS Compliant
• Sampling Rate: 470Hz
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: EVAL-AD7785EBZ - BOARD EVALUATION FOR AD7785
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Figure 14. Filter Profile with Update Rate = 16.7 Hz
Figure 15. Filter Profile with Update Rate = 242 Hz
Figure 16. Filter Response at 470 Hz Update Rate
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Rev. 0 | Page 21 of 32
DIGITAL INTERFACE
The programmable functions of the AD7785 are controlled
using a set of on-chip registers. Data is written to these registers
via the serial interface of the device; read access to the on-chip
registers is also provided by this interface. All communications
with the device must start with a write to the communications
register. After power-on or reset, the device expects a write to
its communications register. The data written to this register
determines whether the next operation is a read operation or a
write operation and determines to which register this read or
write operation occurs. Therefore, write access to any of the
other registers on the part begins with a write operation to the
communications register followed by a write to the selected
register. A read operation from any other register (except when
continuous read mode is selected) starts with a write to the
communications register followed by a read operation from the
selected register.
The serial interface of the AD7785 consists of four signals: CS ,
DIN, SCLK, and DOUT/ RDY . The DIN line is used to transfer
data into the on-chip registers, and DOUT/ RDY is used for
accessing from the on-chip registers. SCLK is the serial clock
input for the device, and all data transfers (either on DIN or
DOUT/ RDY ) occur with respect to the SCLK signal. The
DOUT/ RDY pin operates as a data-ready signal also; the line
going low when a new data-word is available in the output
register. It is reset high when a read operation from the data
register is complete. It also goes high prior to the updating of
the data register to indicate when not to read from the device to
ensure that a data read is not attempted while the register is
being updated. CS is used to select a device. It can be used to
decode the AD7785 in systems where several components are
connected to the serial bus.
AD7785