EVAL-AD7401EDZ

Manufacturer Part NumberEVAL-AD7401EDZ
DescriptionEVALUATION BOARD I.C.
ManufacturerAnalog Devices Inc
SeriesiCoupler®
EVAL-AD7401EDZ datasheets
 


Specifications of EVAL-AD7401EDZ

Number Of Adc's1Number Of Bits16
Sampling Rate (per Second)20MData InterfaceSerial
Inputs Per Adc1 DifferentialInput Range±320 mV
Power (typ) @ Conditions100mW @ 20MSPSVoltage Supply SourceSingle Supply
Operating Temperature-40°C ~ 105°CUtilized Ic / PartAD7401
Lead Free Status / RoHS StatusLead free / RoHS Compliant  
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FEATURES
20 MHz maximum external clock rate
Second-order modulator
16 bits no missing codes
±2 LSB INL typical at 16 bits
3.5 μV/°C maximum offset drift
On-board digital isolator
On-board reference
Low power operation: 20 mA maximum at 5.25 V
−40°C to +105°C operating range
16-lead SOIC package
Safety and regulatory approvals
UL recognition
5000 V rms for 1 minute per UL 1577
CSA Component Acceptance Notice #5A
VDE Certificate of Conformity
DIN V VDE V 0884-10 (VDE V 0884-10):2006-12
V
= 891 V peak
IORM
APPLICATIONS
AC motor controls
Data acquisition systems
A/D + opto-isolator replacements
V
+
IN
Σ-∆ ADC
V
IN
REF
CONTROL LOGIC
Rev. C
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
Isolated Sigma-Delta Modulator
GENERAL DESCRIPTION
The AD7401
that converts an analog input signal into a high speed, 1-bit data
stream with on-chip digital isolation based on Analog Devices,
Inc. iCoupler® technology. The AD7401 operates from a 5 V
power supply and accepts a differential input signal of ±200 mV
(±320 mV full scale). The analog input is continuously sampled
by the analog modulator, eliminating the need for external
sample-and-hold circuitry. The input information is contained
in the output stream as a density of ones with a data rate up to
20 MHz. The original information can be reconstructed with an
appropriate digital filter. The serial I/O can use a 5 V or a 3 V
supply (V
The serial interface is digitally isolated. High speed CMOS,
combined with monolithic air core transformer technology,
means the on-chip isolation provides outstanding performance
characteristics, superior to alternatives such as optocoupler
devices. The part contains an on-chip reference. The AD7401
is offered in a 16-lead SOIC and has an operating temperature
range of −40°C to +105°C.
An internal clock version, AD7400, is also available.
1
Protected by U.S. Patents 5,952,849; 6,873,065; and 7,075,329. Other patents
pending.
FUNCTIONAL BLOCK DIAGRAM
V
DD1
UPDATE
ENCODE
WATCHDOG
DECODE
GND
1
Figure 1.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
AD7401
1
is a second-order, sigma-delta (Σ-Δ) modulator
).
DD2
V
DD2
AD7401
WATCHDOG
DECODE
MDAT
UPDATE
MCLKIN
ENCODE
GND
2
www.analog.com
©2006–2011 Analog Devices, Inc. All rights reserved.

EVAL-AD7401EDZ Summary of contents

  • Page 1

    FEATURES 20 MHz maximum external clock rate Second-order modulator 16 bits no missing codes ±2 LSB INL typical at 16 bits 3.5 μV/°C maximum offset drift On-board digital isolator On-board reference Low power operation maximum at 5.25 V ...

  • Page 2

    ... Circuit Information.................................................................... 13   Analog Input ............................................................................... 13   Differential Inputs ...................................................................... 14   Digital Filter ................................................................................ 15   Applications Information .............................................................. 17   Grounding and Layout .............................................................. 17 Evaluating the AD7401 Performance ...................................... 17   Insulation Lifetime ..................................................................... 17   Outline Dimensions ....................................................................... 18   Ordering Guide .......................................................................... 18   12/06—Rev Rev. A Changes to Features and General Description ..............................1 Changes to Table 1.............................................................................3 Changes to Table 2 ...

  • Page 3

    SPECIFICATIONS DD1 DD2 MHz maximum, tested with Sinc MCLK Table 1. Parameter STATIC PERFORMANCE Resolution 3 Integral Nonlinearity 3 Differential Nonlinearity 3 ...

  • Page 4

    AD7401 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage POWER REQUIREMENTS V DD1 V DD2 6 I DD1 7 I DD2 1 Temperature range is −40°C to +85°C. 2 All voltages are relative to their ...

  • Page 5

    INSULATION AND SAFETY-RELATED SPECIFICATIONS Table 3. Parameter Input-to-Output Momentary Withstand Voltage Minimum External Air Gap (Clearance) Minimum External Tracking (Creepage) Minimum Internal Gap (Internal Clearance) Tracking Resistance (Comparative Tracking Index) Isolation Group REGULATORY INFORMATION Table CSA Recognized ...

  • Page 6

    AD7401 DIN V VDE V 0884-10 (VDE V 0884-10) INSULATION CHARACTERISTICS This isolator is suitable for reinforced electrical isolation only within the safety limit data. Maintenance of the safety data is ensured by means of protective circuits. Table 5. Description ...

  • Page 7

    ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. All voltages are relative to A their respective ground. Table 6. Parameter V to GND DD1 GND DD2 2 Analog Input Voltage to GND 1 Digital Input Voltage ...

  • Page 8

    AD7401 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 8. Pin Function Descriptions Pin No. Mnemonic Description Supply Voltage. 4 5.25 V. This is the supply voltage for the isolated side of the AD7401 and is relative ...

  • Page 9

    TYPICAL PERFORMANCE CHARACTERISTICS T = 25°C, using a 25 kHz brick wall filter, unless otherwise noted. A 100 90 80 MCLKIN = 16MHz MCLKIN = 5MHz MCLKIN = 10MHz 200mV p-p SINE WAVE ON ...

  • Page 10

    AD7401 250 4. DD1 DD2 DD1 200 MCLKIN = 16MHz MCLKIN = 10MHz 4.5V V DD1 DD2 DD1 150 MCLKIN = 5MHz MCLKIN = 5MHz ...

  • Page 11

    4.5V TO 5.25V DD1 DD2 6 MCLKIN = 16MHz MCLKIN = 10MHz 4 2 MCLKIN = 5MHz 0 –2 –4 –6 –8 V – DC INPUT (V) IN Figure 18. I vs. V − DC ...

  • Page 12

    AD7401 TERMINOLOGY Differential Nonlinearity Differential nonlinearity is the difference between the measured and the ideal 1 LSB change between any two adjacent codes in the ADC. Integral Nonlinearity Integral nonlinearity is the maximum deviation from a straight line passing through ...

  • Page 13

    THEORY OF OPERATION CIRCUIT INFORMATION The AD7401 isolated Σ-Δ modulator converts an analog input signal into a high speed (20 MHz maximum), single-bit data stream; the time average of the modulator’s single-bit data is directly proportional to the input signal. ...

  • Page 14

    AD7401 DIFFERENTIAL INPUTS The analog input to the modulator is a switched capacitor design. The analog signal is converted into charge by highly linear sampling capacitors. A simplified equivalent circuit diagram of the analog input is shown in Figure 24. ...

  • Page 15

    DIGITAL FILTER 3 A Sinc filter is recommended for use with the AD7401. This filter can be implemented on an FPGA or possibly a DSP. The following Verilog code provides an example of a Sinc implementation on a Xylinx® Spartan-II ...

  • Page 16

    AD7401 always @ (posedge word_clk or posedge reset) if(reset) begin acc3_d2 <= 0; diff1_d <= 0; diff2_d <= 0; diff1 <= 0; diff2 <= 0; diff3 <= 0; end else begin diff1 <= acc3 - acc3_d2; diff2 <= diff1 - ...

  • Page 17

    ... All insulation structures, subjected to sufficient time and/or voltage, are vulnerable to breakdown. In addition to the testing performed by the regulatory agencies, Analog Devices has carried out an extensive set of evaluations to determine the lifetime of the insulation structure within the AD7401. These tests subjected populations of devices to continuous cross-isolation voltages ...

  • Page 18

    ... AD7401YRW-REEL −40°C to +105°C AD7401YRW-REEL7 −40°C to +105°C AD7401YRWZ −40°C to +105°C AD7401YRWZ-REEL −40°C to +105°C AD7401YRWZ-REEL7 −40°C to +105°C EVAL-AD7401EDZ EVAL-CED1Z RoHS Compliant Part. 10.50 (0.4134) 10.10 (0.3976 7.60 (0.2992) 7.40 (0.2913 ...

  • Page 19

    NOTES Rev Page AD7401 ...

  • Page 20

    AD7401 NOTES ©2006–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05851-0-1/11(C) Rev Page ...