EVAL-AD7401EDZ Analog Devices Inc, EVAL-AD7401EDZ Datasheet - Page 6

• Manufacturer Part Number: EVAL-AD7401EDZ
• Description: EVALUATION BOARD I.C.
• Manufacturer: Analog Devices Inc
• Series: iCoupler®r

Specifications of EVAL-AD7401EDZ

• Number Of Adc's: 1
• Number Of Bits: 16
• Sampling Rate (per Second): 20M
• Data Interface: Serial
• Inputs Per Adc: 1 Differential
• Input Range: ±320 mV
• Power (typ) @ Conditions: 100mW @ 20MSPS
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 105°C
• Utilized Ic / Part: AD7401
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

EVAL-AD7400/AD7401
SOCKETS
There are four SMB input sockets relevant to the operation
of the AD7400 or ADAD7401 on this evaluation board. All
of these sockets are used for applying an externally generated
signal to the evaluation board. When operating the board with
the EVAL-CED1Z, the only external sockets necessary are those
used to supply the differential input signals to the analog inputs
of the ADC (that is, J2 (V
are optional and if they are not used, their signals are supplied
by the EVAL-CED1Z. Most of these sockets are used when
operating the board as a standalone unit, as all the signals
required are supplied from external sources. The functions
of these sockets are outlined in Table 4.
The V
the device, must be supplied by an external source via the J1-1
connector. The V
external source via the J4 connector.
Table 4. Socket Functions
Socket
J2 (V
J3 (V
J5 (MCLKOUT/
MCLKIN)
J6 (MDAT)
CONNECTORS
There are three connectors on the EVAL-AD7400/AD7401 as
outlined in Table 5.
Table 5. Connector Functions
Connector
J1-1
J1-2
J1-3
J4-1
J4-2
J12
TEST POINTS
There are numerous test points on the EVAL-AD7400/AD7401.
These testpoints enable the user to have easy access to these
signals for probing, evaluation, and debugging.
IN
IN
+)
−)
DD1
supply, which is the supply for the isolated side of
Function
External V
External GND
External −5 V power connector.
External V
GND
SPORT connector for the digital interface and
power supply connections.
Function
Subminiature BNC socket for a unipolar
differential input that is applied directly to the
V
Subminiature BNC socket for a unipolar
differential input that is applied directly to the
V
Subminiature BNC socket for the MCLKOUT
output on the AD7400 or subminiature BNC
socket for the MCLKIN input to the AD7401.
Subminiature BNC socket for the MDAT output.
DD2
IN
IIN
2
+ pin of the AD7400 or AD7401.
power connector.
− pin of the AD7400 or AD7401.
supply must be supplied by 3.3 V from an
DD1
DD2
IN
+), J3 (V
power connector.
power connector.
1
power connector.
IN
−)). All of the other sockets
Rev. 0 | Page 6 of 12
OPERATING WITH THE EVAL-CED1Z
The evaluation board can be operated in standalone mode
or operated in conjunction with the EVAL-CED1Z. This
evaluation board controller is available from Analog Devices
under the order entry EVAL-CED1Z.
When interfacing the EVAL-AD7400/AD7401 directly to
the EVAL-CED1Z, the control signals to operate the EVAL-
AD7400/AD7401 are provided by the EVAL-CED1Z. The
device supplies, V
by an external source via the J1 and J4 connectors. If the
AD797 op amps are not being used, then the −5 V is not
required.
The AD7400 and AD7401 are isolated Σ-Δ modulators that
convert an analog input signal into a high speed (10 MHz
typical for AD7400 and 20 MHz for the AD7401), single-
bit data stream. The time average of the single-bit data from
the modulator is directly proportional to the input signal. To
generate an output digital word similar to a conventional ADC
the 1 bit output data stream from the AD7400 or AD7401 needs
to be processed by a digital filter. A sinc3 filter is recommended
for use with a decimation rate of 256, this results in a 16-bit
word with a throughout rate of 39 kHz, assuming a 10 MHz
clock frequency. The sinc3 filter has been implemented in the
FPGA on the EVAL-CED1Z and, therefore, the performance
results displayed by the software are generated using this filter
with a decimation rate of 256.
For the AD7401 the MCLKIN is supplied by the EVAL-CED1Z.
The MSCLK frequency is set at 16 MHz. This gives a through-
put rate of 62.5 kSPS for a decimation rate of 256. The software
allows the user to change the throughput rate by effectively
modifying the decimation rate.
Software to communicate with the EVAL-CED1Z and
AD7400 or AD7401 is provided with the EVAL-AD7400/
AD7401 package.
The SPORT connector on the EVAL-AD7400/AD7401 plugs
directly into the SPORT connector on the EVAL-CED1Z
board. The EVAL-CED1Z board is powered from a 7 V, 15 W
power supply which accepts input voltages from 100 V to 240 V
ac and contains the relevant adaptors for worldwide use. The
power supply is provided with the EVAL-CED1Z.
Connection between the EVAL-CED1Z and the USB port of a
PC is via a standard USB 2.0 connection cable that is provided
as part of the EVAL-CED1Z package.
DD1
, V
DD2
and the −5 V, need to be supplied