EVAL-AD7401AEDZ

Manufacturer Part NumberEVAL-AD7401AEDZ
DescriptionEVALUATION BOARD I.C.
ManufacturerAnalog Devices Inc
SeriesiCoupler®
EVAL-AD7401AEDZ datasheets
 


Specifications of EVAL-AD7401AEDZ

Number Of Adc's1Number Of Bits16
Sampling Rate (per Second)20MData InterfaceSerial
Inputs Per Adc1 DifferentialInput Range±320 mV
Power (typ) @ Conditions105mW @ 20MSPSVoltage Supply SourceSingle Supply
Operating Temperature-40°C ~ 125°CUtilized Ic / PartAD7401A
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
1 μV/°C typical offset drift
On-board digital isolator
On-board reference
±250 mV analog input range
Low power operation: 17 mA typical at 5.5 V
−40°C to +125°C operating range
16-lead SOIC package
Internal clock version: AD7400A
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
Shunt current monitoring
Data acquisition systems
Analog-to-digital and opto-isolator replacements
V
+
IN
Σ-∆ ADC
V
IN
REF
CONTROL LOGIC
1
Protected by U.S. Patents 5,952,849; 6,873,065; and 7,075,329. Other patents pending.
Rev. B
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 AD7401A
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 AD7401A operates from a 5 V
power supply and accepts a differential input signal of ±250 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 Analog Devices, Inc., iCoupler® 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 AD7401A
is offered in a 16-lead SOIC and has an operating temperature
range of −40°C to +125°C.
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
AD7401A
1
is a second-order, sigma-delta (Σ-Δ) modulator
).
DD2
V
DD2
AD7401A
WATCHDOG
DECODE
MDAT
UPDATE
MCLKIN
ENCODE
GND
2
www.analog.com
©2008–2011 Analog Devices, Inc. All rights reserved.

EVAL-AD7401AEDZ 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 1 μV/°C typical offset drift On-board digital isolator On-board reference ±250 mV analog input range Low power operation: 17 ...

  • Page 2

    ... Differential Inputs ...................................................................... 15   Current Sensing Applications................................................... 15   Voltage Sensing Applications.................................................... 15   Digital Filter ................................................................................ 16   Applications Information .............................................................. 18 Grounding and Layout .............................................................. 18   Evaluating the AD7401A Performance ................................... 18   Insulation Lifetime ..................................................................... 18   Outline Dimensions ....................................................................... 19   Ordering Guide .......................................................................... 19   Rev Page         ...

  • Page 3

    SPECIFICATIONS DD1 DD2 1 16 MHz maximum, tested with sinc3 filter, 256 decimation rate, as defined by Verilog code, unless otherwise noted. Table 1. Parameter ...

  • Page 4

    AD7401A Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage POWER REQUIREMENTS V DD1 V DD2 5 I DD1 6 I DD2 Figure 17. Power Dissipation 1 For f > 16 MHz to 20 MHz, mark ...

  • Page 5

    TIMING SPECIFICATIONS DD1 DD2 Table 2. 1 Parameter Limit MIN MAX MCLKIN ...

  • Page 6

    AD7401A 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 ...

  • Page 7

    DIN V VDE V 0884-10 (VDE V 0884-10):2006-12 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 INSTALLATION ...

  • Page 8

    AD7401A 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 ...

  • Page 9

    PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 8. Pin Function Descriptions Pin No. Mnemonic Description Supply Voltage, 4 5.5 V. This is the supply voltage for the isolated side of the AD7401A and is relative to ...

  • Page 10

    AD7401A TYPICAL PERFORMANCE CHARACTERISTICS T = 25°C, using 25 kHz brick-wall filter, unless otherwise noted. A 100 90 80 MCLKIN = 16MHz MCLKIN = 5MHz MCLKIN = 10MHz 200mV p-p SINE WAVE ON V ...

  • Page 11

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

  • Page 12

    AD7401A 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 − ...

  • Page 13

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

  • Page 14

    AD7401A THEORY OF OPERATION CIRCUIT INFORMATION The AD7401A isolated Σ-Δ modulator converts an analog input signal into a high speed (20 MHz maximum), single-bit data stream; the time average single-bit data from the modulators is directly proportional to the input ...

  • Page 15

    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. A ...

  • Page 16

    AD7401A DIGITAL FILTER The overall system resolution and throughput rate is determined by the filter selected and the decimation rate used. The higher the decimation rate, the greater the system accuracy, as illus- trated in Figure 26. However, there is ...

  • Page 17

    Z = one sample delay MCLKOUT = modulators conversion bit rate */ always @ (posedge mclk1 or posedge reset) if (reset) begin /*initialize acc registers on reset*/ acc1 <= 0; acc2 <= 0; acc3 <= 0; end else begin /*perform ...

  • Page 18

    ... PC via the EVAL-CED1Z. The software also includes a sinc3 filter implemented on an FPGA. The evaluation board is used in conjunction with the EVAL- CED1Z board and can also be used as a standalone board. The software allows the user to perform ac (fast Fourier transform) and dc (histogram of codes) tests on the AD7401A ...

  • Page 19

    ... PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. ORDERING GUIDE Model 1 Temperature Range AD7401AYRWZ −40°C to +125°C AD7401AYRWZ-RL −40°C to +125°C EVAL-AD7401AEDZ EVAL-CED1Z RoHS Compliant Part. 10.50 (0.4134) 10.10 (0.3976 7.60 (0.2992) 7.40 (0.2913 ...

  • Page 20

    AD7401A NOTES ©2008–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07332-0-3/11(B) Rev Page ...