AN-2046: IEC 61000-4-x and CISPR 11 Tested Analog Output Design with the AD5758 and ADP1031 for Industrial Process Control Applications

INTRODUCTION

The AD5758 is a single-channel, 16-bit, voltage and current output digital-to-analog converter (DAC) with on-chip dynamic power control (DPC) and HART^® connectivity. The AD5758 is designed to work with programmable logic controller (PLC) and distributed control system (DCS) modules of industrial process control applications.

The ADP1031 is a high performance, isolated micropower management unit (microPMU) that provides three isolated power rails. Additionally, the ADP1031 contains four high speed serial peripheral interface (SPI) isolation channels and three general-purpose isolators for channel to channel applications where low power dissipation and small solution size are required.

This application note describes an electromagnetic compatibility (EMC) tested solution of the analog output design with the ADP1031ACPZ-1-R7 (hereafter referred to as the ADP1031) and the AD5758 output voltage (V_OUT) and output current (I_OUT) for industrial process control with dynamic power control. The IEC 61000-4-x set of standards cover the evaluation of the immunity of electrical and electronic equipment at a system level.

The AD5758 and ADP1031 EMC test board is characterized to ensure that the circuit performance is not affected by radiated RF or conducted RF disturbances, and has sufficient immunity against electrostatic discharge (ESD), electrical fast transients (EFT), and surge. The EMC test board was also tested per the CISPR 11 standard, in which the radiated emissions of the board are well below the Class B limits due to the improved electromagnetic interference (EMI) performance of the ADP1031. The ADP1031 passes the CISPR 11 Class B limits with a greater than 9 dB margin, due to its high integration and design optimizations. The AD5758 and ADP1031 EMC test board design significantly reduces the risk of failing IEC 61000-4-x and CISPR 11 certification in multichannel analog output applications with the AD5758 and ADP1031.

The AN-1599 Application Note, IEC 61000-4-x and CISPR 11 Tested Analog Output Design with the AD5758 for Industrial Process Control Applications, describes the AD5758 EMC test board, which shares the same blank PCB of this board but is assembled with partially different bill of materials (BOM). The AD5758 EMC test board uses discrete ICs to implement the power and digital isolation of the ADP1031. The AD5758 EMC test board has comparable immunity but only passes CISPR 11 Class A limits. Refer to the AN-1599 Application Note for additional details.

Figure 1. AD5758 and ADP1031 EMC Test Board Photograph

SYSTEM DESIGN

AD5758 DAC DESCRIPTION

The AD5758 is a single-channel, voltage and current output DAC that operates with a 60 V maximum operating voltage between the AV_SS and AV_DD1 rails. The on-chip DPC minimizes package power dissipation, which is achieved by regulating the supply voltage (V_DPC+) to the VI_OUT output driver circuitry from 5 V to 27 V using a buck dc-to-dc converter. The C_HART pin enables a HART signal to couple to the current output.

The device uses a versatile, 4-wire serial peripheral interface (SPI) that operates at clock rates of up to 50 MHz and is compatible with standard SPI, QSPI^™, MICROWIRE^™, DSP, and microcontroller interface standards. The interface also features an optional SPI cyclic redundancy check (CRC) and a watchdog timer (WDT). The AD5758 offers diagnostic features, such as output current monitoring and an integrated 12-bit diagnostic analog-to-digital converter (ADC). Additional robustness is provided by the inclusion of a fault protection switch on the VI_OUT, +V_SENSE, and −V_SENSE pins.

For full details, refer to the AD5758 data sheet.

ADP1031 MICROPOWER MANAGEMENT UNIT DESCRIPTION

The ADP1031 is a high performance, isolated microPMU that combines an isolated flyback dc-to-dc regulator, an inverting dc-to-dc regulator, and a buck dc-to-dc regulator, providing three isolated power rails.

CIRCUIT DESCRIPTION

This circuit is a single-channel, isolated, industrial voltage and current output module for harsh EMI/EMC environments featuring the AD5758 DAC and ADP1031 microPMU with seven digital isolators. This design is targeted for PLC and DCS applications. The AD5758 and ADP1031 EMC test board is designed to satisfy the IEC 6100-4-x and CISPR 11 standards intended for use in the harsh industrial environments that is stated in IEC 61000-6-2 generic standard. The AD5758 and ADP1031 EMC test board is a BOM variant of the AD5758 EMC test board described in the AN-1599. These two boards are assembled on the same blank PCB. The only difference of the variant in this application note is that the ADP1031 replaces the discrete power and digital isolation implementation consisting of the LT8300, ADP2360, ADuM141D, ADuM142D, and ADM6339.

Powering the Design

The AD5758 and ADP1031 EMC test board is powered by two separate supplies. The first 24 V input is supplied to the ADP1031, which greatly simplifies the isolated power supply design. On this EMC test board, the ADP1031 is used to generate an isolated 20 V and powers the AV_DD1 pin of the AD5758. The ADP1031 5.15 V V_OUT2 and −15 V V_OUT3 also supply the voltage for the AV_DD2 and AV_SS pins of the AD5758, respectively. The second 24 V supply powers the circuits on the system side domain, including the microprocessor and digital isolator. The ADP7142 steps the 24 V supply down to 5 V, which supplies the circuits where 5 V logic or 5 V power is required. A low dropout (LDO) regulator, the ADP124, further regulates the 5 V supply to 3 V for low power components, including the ADuCM3029. The AD5758 and ADP1031 EMC test board can operate from a single 24 V supply, but the two 24 V supplies must be isolated from each other to demonstrate that the system power and the field power are separate power supplies. The two 24 V supplies are meant to mimic the typical use case, where the system power and the field power are supplied separately within the system.

Isolation Considerations

A properly placed isolation barrier is often the first method used to improve EMC robustness. The ADP1031 provides electrical isolation between the field side AD5758 and the system side microcontroller unit (MCU). Take precautions to achieve optimal EMC and EMI performance. For optimum radiated emission performance, it is recommended to connect an inductor and capacitor (LC) filter, consisting of a ferrite bead and 100 nF and 10 nF capacitors in parallel to each other, to the MVDD, SVDD1, and SVDD2 pins. A 0.001 μF ceramic capacitor across the isolation barrier also reduces the radiated emission. See the AN-1109 Application Note, Recommendations for Control of Radiated Emissions with iCoupler Devices, for more details.

The ADP1031 isolated flyback converter drives a flyback transformer. A 1 nF, 3 kV capacitor across the primary and secondary side provides a return path for the image current.

The ADuCM3029 ultra low power Arm^® Cortex^®-M3 MCU provides local control and data communication for the AD5758 and ADP1031 EMC test board. The ADuCM3029 has an acceptable emission profile and has adequate immunity in the IEC 61000-4-x tests.

Figure 2. AD5758 and ADP1031 EMC Test Board in Circuit

PRINTED CIRCUIT BOARD

The AD5758 and ADP1031 EMC test board is built on a FR4 4-layer printed circuit board (PCB). The primary side and the secondary side of the PCB have 0.5 oz copper foil, and the internal layers are on 1 oz copper. The PCB stack is illustrated in Figure 3.

COMPONENT PLACEMENT AND LAYOUT CONSIDERATIONS

This section describes design considerations for optimal EMC and EMI performance of the AD5758 with the minimum man-datory components (general recommendations on component placement, and distances from connector).

Place the digital interface side of the AD5758 close to the isolators. The damping resistors (around a few tens of ohms to hundreds of ohms) on the digital lines attenuate the electrical transients due to the CMOS switching on and off, which helps to reduce EMI. The VI_OUT side of the AD5758 must be close to the 4-pin output terminal block on the edge of the AD5758 and ADP1031 EMC test board.

Other Component Considerations

The AD5758 and ADP1031 EMC test board uses 0.1 μF, 50 V, X7R, 10%, low equivalent series resistance (ESR) ceramic capacitors in the C0603 footprint for the decoupling capacitors, which is a trade-off among considerations for performance, derating, cost, and space savings. In some cases, when closer decoupling is required, a 1 nF, 25 V, X7R capacitor in the C0402 footprint is applied.

Voltage Supply Protection

The scope of EMC or EMI evaluation and demonstration focuses on the AD5758 and its companion parts. The two 24 V power supply circuits on the AD5758 and ADP1031 EMC test board provide the necessary voltages for the function of the board. The supply circuits are not intended to match the robustness of the power supply module or the backplane supply in the automation control system of a user. Therefore, only basic protections are implemented for these supply circuits. In the 24 V supply for the system side, a 1 nF capacitor is placed next to each pin of the power input terminal to the protected ground, where transient energy can be discharged to the earth ground through a 3.3 nF, 3 kV capacitor. The 4.7 MΩ resistor bleeds energy to the earth, which can accumulate on the protected ground. A transient voltage suppression (TVS) diode is inserted to prevent miswiring to the power supply input. The TVS diode clamps the transient voltage from going higher than 33 V (nominal). A common-mode inductor attenuates the emissions escaping from the downstream circuits. A second TVS diode is inserted after the inductor provides further clamping for the transient. The 24 V power supply for the field side has a similar protection scheme.

ESD Protection

The AD5758 and ADP1031 EMC test board must have appropriate ESD protection circuitry. The protection consists of a current limiting resistor, a transient voltage clamp, and a transient energy diverting capacitor.

There are three minimum mandatory components for EMC and EMI of the AD5758. A 10 Ω resistor on the trace between the AD5758 VI_OUT pin and the terminal block limits the transient current to and from the device. The TVS diode is crucial to clamp the electrical transient on the board during EMC events. A TVS diode is inserted between the AD5758 and the output terminal block. The pins of the TVS diode are directly routed to the VI_OUT and RETURN screws (on the P4 terminal) with short and heavy traces. A 10 nF, 50 V, X7R capacitor located in parallel to the TVS diode diverts the small amount of high frequency transient to the RETURN screw. Optional clamp diodes connected to the AV_DD1 and AV_SS rails can be added to the VI_OUT line to further improve the robustness. However, these diodes are unnecessary for the AD5758 and ADP1031 EMC test board because the EMC and EMI performance objectives are met without them.

Figure 4. AD5758 and ADP1031 Bypass and Peripheral Circuit

CIRCUIT EVALUATION AND TEST

The AD5758 reference design is run by being connected to a PC or run in standalone mode. The graphic user interface (GUI) on the PC configures the running parameters, such as DAC output range, output code, and ADC sequencing. The GUI displays the fault flag map and plots the reading from the AD5758 on-chip, diagnostic ADC nodes.

When the operational parameters are programmed in the on-board flash memory, the board can be disconnected from the PC or controller board when the software is operating. To operate the board, power up the board and press the RUN or STOP buttons on the AD5758 and ADP1031 EMC test board.

Figure 5 shows the general setup of the AD5758 and ADP1031 EMC test board for EMC tests. Before and after each potentially destructive EMC test, the precision bench digital multimeter (DMM) takes 300 measurements of the AD5758 output on the load resistor. The deviation between the two sets of DMM measurements must stay within the predefined range to meet the performance criterion. The maximum allowable deviation is 0.1% of full scale, which aligns with the common requirements of the industrial automation applications.

During the nondestructive EMC tests, the bench DMM contin-uously measures the AD5758 output on the load resistor. The measurements taken during and after the EMC event are compared to the average of the DMM measurement before the EMC event for judging the performance criterion.

In the emissions test, the AD5758 is configured to output the full-scale voltage or current that is being refreshed at 1 kHz, and the AD5758 and ADP1031 EMC test board runs in standalone mode. The only auxiliary devices in this setup are two 24 V battery packs that power the AD5758 and ADP1031 EMC test board. These battery packs are assumed to not contribute EMI.

SOFTWARE NEEDED

To perform EMC testing on the AD5758, the following software is required:

Firmware, Revision 57-58-E0-01 on the AD5758 and ADP1031 EMC test board
AD5758 system EMC GUI software, Revision 1.0.0.1
Keysight Technologies BenchVue™ software, Version 2.6

EQUIPMENT NEEDED

To perform EMC testing on the AD5758, the following equipment is required:

Optical USB transceiver board
Industrial fiber optic cable
PC running Windows^® 7, 64-bit version, image model: V3.0.2011.10.14
DC power supplies: Agilent 3630A and Agilent 3631A
Digital multimeter: Keysight 33470A
2 m (1 pair twisted) conductor multiconductor cable: Belden 8761
Line filter: Schaffner FN353Z-30-33

A load resistor is connected to the AD5758 by a 2 m cable (Belden 8761, twisted, shielded pair). In current output mode, the load is a radial leaded, 500 Ω, ±0.005%, ±0.8 ppm/°C, 600 mW, 300 V foil resistor. In voltage output mode, the load is a radial leaded, 1 kΩ, ±0.01%, ±0.8 ppm/°C, 600 mW, 300 V foil resistor.

A pair of twisted leads, followed by a low-pass filter, probes the voltage across the load resistor. The filter output is wired to the Keysight 33470A DMM with a pair of twisted leads. The DMM integration time is set to a 0.02 power line cycle (400 μs). A USB cable connects the DMM to the PC. The AD5758 GUI software monitors the AD5758 status register every 1 ms via the electrically isolated data link.

The AD5758 system EMC GUI software sends parameters to the local microprocessor to write to the AD5758. For each EMC and EMI test item, the AD5758 and ADP1031 EMC test board is tested in voltage output mode and current output mode.

Two output conditions are checked in each output mode. The first condition is an alternated write of 0xFFFF and 0x8000 to the AD5758 every 2 sec to verify that the AD5758 output is actively updated according to the input code during the EMC tests. The second condition is a fixed write of 0xFFFF to the AD5758 every 1 ms for the simplified calculation of the AD5758 output deviation, during and after EMC events.

Figure 6. AD5758 System EMC Software GUI, Toggling Output

Figure 7. AD5758 System EMC Software GUI, Stable Output

The AD5758 and ADP1031 EMC test board is tested to and meets the CISPR 11 and IEC 61000-4-x standards described in Table 1 and Table 2. Table 3 describes the performance criteria listed in Table 2.

STANDARDS AND PERFORMANCE CRITERIA

The AD5758 and ADP1031 EMC test board is designed to pass the EMC and EMI test items and limits, and to meet the performance criteria. The EMC test board limits and performance criteria are defined according to the IEC 61000-6-2 and the IEC 61131-2 standards. According to these standards, the following six applicable tests were selected:

IEC 61000-4-2
IEC 61000-4-3
IEC 61000-4-4
IEC 61000-4-5
IEC 61000-4-6
CISPR 11

Table 1. Emissions Performance Summary
Test	Basic Standard	Frequency Range (MHz)	Limits	Measured Minimum Margin (dBμV/m)	Result
Radiated Emissions	CISPR 11, Class B	30 to 1000	See Table 11 and Table 12	9.07	Pass

Table 2. Immunity Performance Summary
Test	Basic Standard	Test Levels	Performance Criterion	Measured Minimum Margin	Result
Conducted Immunity	IEC 61000-4-6	20 V/m	A	See Table 4	Pass
Radiated Immunity	IEC 61000-4-3	20 V/m	A	See Table 10	Pass
ESD	IEC 61000-4-2 IEC 61000-4-2 IEC 61000-4-2	±6 kV contact ±12 kV air ±30 kV coupling	B B B	See Table 5 See Table 6 See Table 7	Pass Pass Pass
EFT	IEC 61000-4-4	±4 kV	B	See Table 8	Pass
Surge	IEC 61000-4-5	±4 kV	B	See Table 9	Pass

Table 3. Performance Criteria
Performance Criterion	Description
A	Normal performance within an error band specified by the manufacturer.
B	Temporary loss of function or degradation of performance, which ceases after the disturbance is removed. The equipment under test (EUT) recovers its normal performance without operator intervention.
C	Temporary loss of function or degradation of performance. Correction of performance requires operator intervention, such as manual restart, power off, or power on.
D	Loss of function or degradation of performance, which is not recoverable. Permanent damage to hardware or software, or loss of data.

EMC AND EMI MEASUREMENT RESULTS OF THE AD5758 AND ADP1031 EMC TEST BOARD

CONDUCTED IMMUNITY

As per IEC 61000-4-6, the EUT is placed on an insulating support that is 0.1 m high above a ground reference plane. All cables exiting the EUT are supported at a height of at least 30 mm above the ground reference plane. The interference is injected with a coupling and decoupling network (CDN), 801A. The cable is decoupled by an attenuation clamp, KEMZ 801A. The frequency range is swept from 150 kHz to 80 MHz (20 V/m) with the disturbance signal of 80% amplitude modulated with a 1 kHz sine wave. The step size is 1% of the start and thereafter 1% of the preceding frequency value where the frequency is swept incrementally. The dwell time of the amplitude-modulated carrier at each frequency is 0.5 sec. During this interval, the DMM is able to complete more than 30 measurements, which is adequate for calculating the error deviation.

Table 4. IEC 61000-4-6 Test Levels and Results
Output Mode	Average Before Zap	During Zap		Average After Zap	Deviation of Full Scale (ppm)	Pass or Fail
Output Mode	Average Before Zap	Minimum	Maximum	Average After Zap	Deviation of Full Scale (ppm)	Pass or Fail
V_OUT = 10 V	9.999341 V	9.997904 V	10.000008 V	9.999395 V	−0.009%, 0.004%	Pass, Criterion A
I_OUT = 20 mA	19.960074 mA	19.959014 mA	19.962312 mA	19.960025 mA	−0.007%, 0.014%	Pass, Criterion A

Figure 8. IEC 61000-4-6 Test Setup Connection Diagram

Figure 9. IEC 61000-4-6 Test Setup Photograph

Figure 10. Voltage Output vs. Frequency, Below 20 V/m

Figure 11. Current Output vs. Frequency, Below 20 V/m

Figure 12. Voltage Output vs. Measurement Count, Before and After 20 V/m Conducted Susceptibility (CS)

Figure 13. Current Output vs. Measurement Count, Before and After 20 V/m CS

IMMUNITY TO ESD

The test setup consists of a nonconductive table with a height of 0.8 m, standing on the ground reference plane. A 1.6 m × 0.8 m horizontal coupling plane (HCP) is placed on the table. The EUT and its cable are isolated from the coupling plane by an insulating mat that is 0.5 mm thick.

The contact discharges are applied to the VIOUT and RETURN terminal screws of the AD5758 output terminal block (P4). The EUT is exposed to at least 20 discharges at each rating, 10 each at negative and positive polarity. The discharges are repeated at a rate of one discharge per second.

The air discharges are applied to the AD5758 output terminal block. The EUT is exposed to at least 20 discharges at each rating: 10 each at negative and positive polarity. The discharges are repeated at a rate of one discharge per second.

The coupling discharge are applied to the HCP and vertical coupling plane (VCP). The EUT is exposed to at least 20 discharges at each rating: 10 each at negative and positive polarity. The discharges are repeated at a rate of one discharge per second. The coupling plane has two 470 kΩ bleeding resistors to earth ground.

Table 5. IEC 61000-4-2 Test Levels and Results of ±6 kV Contact ESD
Test Level	Output Mode	Zap Point on P4	Before Zap	After Zap	Deviation of Full Scale (ppm)	Pass or Fail
6 kV Contact Discharge	V_OUT = 10 V	VIOUT terminal screw	9.999939 V	9.999964 V	3	Pass, Criterion B
	V_OUT = 10 V	RETURN terminal screw	9.999946 V	9.999965 V	2	Pass, Criterion B
	I_OUT = 20 mA	VIOUT terminal screw	19.961543 mA	19.961512 mA	−2	Pass, Criterion B
	I_OUT = 20 mA	RETURN terminal screw	19.961495 mA	19.961551 mA	3	Pass, Criterion B
−6 kV Contact Discharge	V_OUT = 10 V	VIOUT terminal screw	9.998116 V	9.998157 V	4	Pass, Criterion B
	V_OUT = 10 V	RETURN terminal screw	9.999761 V	9.999805 V	5	Pass, Criterion B
	I_OUT = 20 mA	VIOUT terminal screw	19.961541 mA	19.961490 mA	−3	Pass, Criterion B
	I_OUT = 20 mA	RETURN terminal screw	19.961426 mA	19.961442 mA	1	Pass, Criterion B

Table 6. IEC 61000-4-2 Test Levels and Results of ±12 kV Air ESD
Test Level	Output Mode	Zap Point on P4	Before Zap	After Zap	Deviation of Full Scale (ppm)	Pass or Fail
12 kV Air Discharge	V_OUT = 10 V	VIOUT terminal block	9.999615 V	9.999612 V	−1	Pass, Criterion B
12 kV Air Discharge	I_OUT = 20 mA	VIOUT terminal block	19.960970 mA	19.960972 mA	1	Pass, Criterion B
−12 kV Air Discharge	V_OUT = 10 V	VIOUT terminal block	9.999562 V	9.999572 V	1	Pass, Criterion B
−12 kV Air Discharge	I_OUT = 20 mA	VIOUT terminal block	19.960957 mA	19.961000 mA	2	Pass, Criterion B

Table 7. IEC 61000-4-2 Test Levels and Results of ±30 kV Coupling ESD
Test Level	Output Mode	Zap Point	Before Zap	After Zap	Deviation of Full Scale (ppm)	Pass or Fail
30 kV Coupling Discharge	V_OUT = 10 V	Horizontal plane	10.000360 V	10.000379 V	2	Pass, Criterion B
	V_OUT = 10 V	Vertical plane	10.000385 V	10.000371 V	−2	Pass, Criterion B
	I_OUT = 20 mA	Horizontal plane	19.961024 mA	19.960967 mA	−3	Pass, Criterion B
	I_OUT = 20 mA	Vertical plane	19.961045 mA	19.960978 mA	−4	Pass, Criterion B
−30 kV Coupling Discharge	V_OUT = 10 V	Horizontal plane	10.000398 V	10.000384 V	-2	Pass, Criterion B
	V_OUT = 10 V	Vertical plane	10.000387 V	10.000378 V	−1	Pass, Criterion B
	I_OUT = 20 mA	Horizontal plane	19.961049 mA	19.961004 mA	−3	Pass, Criterion B
	I_OUT = 20 mA	Vertical plane	19.961010 mA	19.960995 mA	−1	Pass, Criterion B

Figure 14. IEC 61000-4-2 Test Setup Connection Diagram, Contact Discharge or Air Discharge

Figure 15. IEC 61000-4-2 Test Setup Connection Diagram, Coupling Discharge

Figure 16. IEC 61000-4-2 Test Setup Photograph

Figure 17. Voltage Output vs. Measurement Count, 6 kV ESD at VIOUT Terminal Screw

Figure 18. Voltage Output vs. Measurement Count, −6 kV ESD at VIOUT Terminal Screw

Figure 19. Voltage Output vs. Measurement Count, 6 kV ESD at RETURN Terminal Screw

Figure 20. Voltage Output vs. Measurement Count, −6 kV ESD at RETURN Terminal Screw

Figure 21. Current Output vs. Measurement Count, 6 kV ESD at VIOUT Terminal Screw

Figure 22. Current Output vs. Measurement Count, −6 kV ESD at VIOUT Terminal Screw

Figure 23. Current Output vs. Measurement Count, 6 kV ESD at RETURN Terminal Screw

Figure 24. Current Output vs. Measurement Count, −6 kV ESD at RETURN Terminal Screw

Figure 25. Voltage Output vs. Measurement Count, 12 kV Air ESD

Figure 26. Voltage Output vs. Measurement Count, −12 kV Air ESD

Figure 27. Current Output vs. Measurement Count, 12 kV Air ESD

Figure 28. Current Output vs. Measurement Count, −12 kV Air ESD

Figure 29. Voltage Output vs. Measurement Count, 30 kV HCP ESD

Figure 30. Voltage Output vs. Measurement Count, −30 kV HCP ESD

Figure 31. Voltage Output vs. Measurement Count, 30 kV VCP ESD

Figure 32. Voltage Output vs. Measurement Count, −30 kV VCP ESD

Figure 33. Current Output vs. Measurement Count, 30 kV HCP ESD

Figure 34. Current Output vs. Measurement Count, −30 kV HCP ESD

Figure 35. Current Output vs. Measurement Count, 30 kV VCP ESD

Figure 36. Current Output vs. Measurement Count, −30 kV VCP ESD

IMMUNITY TO ELECTRICAL FAST TRANSIENTS

Per the IEC 61000-4-4 standard, the EUT is tested with 4000 V discharges on the analog input cable. Positive and negative polarity discharges are applied. The length of the hot wire from the coaxial output of the EFT generator to the terminals on the EUT must not exceed 1 m. The duration time of each test sequential is 1 min. The transient and burst waveform is in accordance with IEC 61000-4-4, 5 ns rising time with 50 ns pulse width.

The configuration consists of a 0.8 m high wooden table, covered with a sheet of copper that is at least 0.25 mm thick, and connected to the protective grounding system. The EUT is placed on a 0.1 m thick isolating support. A minimum distance of 0.5 m is provided between the EUT and the walls of the laboratory.

Table 8. IEC 61000-4-4 Test Levels and Results of ±4 kV EFT
Test Level	Output Mode	Before Zap	After Zap	Deviation of Full Scale (ppm)	Pass or Fail
4 kV EFT	V_OUT = 10 V	10.000216 V	10.000277 V	4	Pass, Criterion B
4 kV EFT	I_OUT = 20 mA	19.960184 mA	19.960118 mA	−5	Pass, Criterion B
−4 kV EFT	V_OUT = 10 V	10.000269 V	10.000254 V	−1	Pass, Criterion B
−4 kV EFT	I_OUT = 20 mA	19.960140 mA	19.960190 mA	4	Pass, Criterion B

Figure 37. IEC 61000-4-4 Test Setup Connection Diagram

Figure 38. IEC 610004-4 Test Setup Photograph

Figure 39. Voltage Output vs. Measurement Count, 4 kV EFT

Figure 40. Voltage Output vs. Measurement Count, −4 kV EFT

Figure 41. Current Output vs. Measurement Count, 4 kV EFT

Figure 42. Current Output vs. Measurement Count, −4 kV EFT

IMMUNITY TO SURGE

Per the IEC 61000-4-5 standard for industrial environments, the surge is a combination wave of 1.2 μs rising time with 50 μs pulse width open circuit voltage and 8 μs rising time with 20 μs pulse width short-circuit current. The EUT is subject to five positive and five negative surges at each rating. The interval between each surge is 1 min. The surge is tested to the AD5758 output cable, which is treated as unshielded asymmetrically operated interconnection lines of the EUT. The surge is applied to the lines via capacitive coupling through CDN 174.

The CDNs do not influence the specified functional conditions of the EUT. The interconnection line between the EUT and the CDNs is 2 m in length or shorter.

Table 9. IEC 61000-4-5 Test Levels and Results
Test Level	Output Mode	Before Zap	After Zap	Deviation of Full Scale (ppm)	Pass or Fail
4 kV Surge	V_OUT = 10 V	9.999588 V	9.999406 V	−12	Pass, Criterion B
4 kV Surge	I_OUT = 20 mA	19.960027 mA	19.960030 mA	1	Pass, Criterion B
−4 kV Surge	V_OUT = 10 V	9.999328 V	9.999389 V	4	Pass, Criterion B
−4 kV Surge	I_OUT = 20 mA	19.959943 mA	19.959980 mA	3	Pass, Criterion B

Figure 43. IEC 61000-4-5 Test Setup Connection Diagram

Figure 44. IEC 61000-4-5 Test Setup Photograph

Figure 45. Voltage Output vs. Measurement Count, Below 4 kV Surge

Figure 46. Voltage Output vs. Measurement Count, Below −4 kV Surge

Figure 47. Current Output vs. Measurement Count, Below 4 kV Surge

Figure 48. Current Output vs. Measurement Count, Below −4 kV Surge

RADIATED IMMUNITY

Per the IEC 61000-4-3 standard for industrial environments, the test is performed in a fully anechoic chamber. The EUT is placed on a 0.8 m high nonconductive table. A DMM, used as auxiliary equipment, is put in a shielded box under the table and probes the AD5758 output at the load resistor. The DMM measurement data is sent to the PC outside the chamber via an Ethernet cable. The transmit antenna is located 3 m from the EUT. The frequency range is swept from 80 MHz to 1000 MHz, and from 1000 MHz to 6000 MHz with the 80% signal amplitude modulated with a 1 kHz sine wave. The frequency range is swept incrementally, and the step size is 1% of the preceding frequency value. The dwell time at each frequency is 1 sec, which is not less than the time necessary for the EUT to respond. During this interval, the DMM is able to complete 20 measurements, which is adequate for calculating the error deviation. The field strength is 20 V/m in the 80 MHz to 1000 MHz range. The field strength for the 1000 MHz to 6000 MHz range is 10 V/m. The test is performed with the EUT exposed to a vertically and horizontally polarized field.

Table 10. IEC 61000-4-3 Test Levels and Results
Frequency Range	Test Level	Antenna Polarization	Output Mode	Average	During Zap (Maximum)	During Zap (Minimum)	Deviation 0f Full Scale (%)	Pass or Fail
80 MHz to 1000 MHz	20 V/m	Horizontal	V_OUT = 10 V	9.999848	10.000866	9.998624	−0.013, 0.010	Pass, Criterion A
	20 V/m	Vertical	V_OUT = 10 V	9.999883	10.001688	9.998599	−0.012, 0.019	Pass, Criterion A
	20 V/m	Horizontal	I_OUT = 20 mA	19.996675	19.998610	19.994331	−0.012, 0.009	Pass, Criterion A
	20 V/m	Vertical	I_OUT = 20 mA	19.996793	20.000425	19.994738	−0.011, 0.018	Pass, Criterion A
1000 MHz to 6000 MHz	10 V/m	Horizontal	V_OUT = 10 V	9.999852	10.000866	9.998709	−0.011, 0.010	Pass, Criterion A
	10 V/m	Vertical	V_OUT = 10 V	9.999827	10.000857	9.998649	−0.012, 0.010	Pass, Criterion A
	10 V/m	Horizontal	I_OUT = 20 mA	19.996832	19.998542	19.994976	−0.010 0.008	Pass, Criterion A
	10 V/m	Vertical	I_OUT = 20 mA	19.996822	19.998695	19.994976	−0.009, 0.010	Pass, Criterion A

Figure 49. IEC 61000-4-3 Test Setup Configuration Diagram

Figure 50. IEC 61000-4-3 Test Setup Photograph

Figure 51. Voltage Output vs. Frequency Below 20 V/m, Horizontal Antenna

Figure 52. Voltage Output vs. Frequency Below 10 V/m, Horizontal Antenna

Figure 53. Voltage Output vs. Frequency Below 20 V/m, Vertical Antenna

Figure 54. Voltage Output vs. Frequency Below 10 V/m, Vertical Antenna

Figure 55. Current Output vs. Frequency Below 20 V/m, Horizontal Antenna

Figure 56. Current Output vs. Frequency Below 10 V/m, Horizontal Antenna

Figure 57. Current Output vs. Frequency Below 20 V/m, Vertical Antenna

Figure 58. Current Output vs. Frequency Below 10 V/m, Vertical Antenna

RADIATED EMISSIONS

Per the CISPR 11 standard, the EUT is placed on top of a rotating table, 0.8 m above the ground, in a 10 m, semianechoic chamber. The table is rotated 360° to identify the position of the highest radiation. The EUT is set 10 m from the interference receiving antenna, which can be set to a horizontal or vertical polarization position. The antennas are mounted on top of a variable height antenna tower. The heights of the antennas vary from 1 m to 4 m above the ground to identify the maximum value of the field strength. The EUT is configured to its typical worst case where the antenna is tuned to a height from 1 m to 4 m, and the table is turned from 0° to 360° to find the maximum reading. The typical worst case for the EUT means that the AD5758 is being refreshed at 1 kHz at its full-scale voltage or current output. The test receiver system is set to quasipeak detection mode. The EUT is powered by two 24 V dc battery packs. Any radiated emission from the auxiliary supply can be excluded.

The AN-1599 describes the AD5758 EMC test board, which shares the same blank PCB of this AD5758 and ADP1031 EMC test board but is assembled with partially different BOM that implements the power and digital isolation with discrete ICs. The AD5758 EMC test board has emission peaks around 205 MHz, which does not satisfy the 6 dB margin against CISPR 11 Class B. The AD5758 and ADP1031 EMC test board in contrast is not only 10 dB lower around the frequencies but also has a very low emissions profile in the range of 30 MHz to 230 MHz where the CISPR 11 Class B limit is more stringent, mainly due to the higher integration and design optimizations of the ADP1031 for EMI.

Table 11. CISPR 11 Radiated Emissions at Critical Frequencies, V_OUT = 10 V
Frequency (MHz)	Result (dBμV)	Limit (dBμV)	Margin (dB)	Height (cm)	Degree (°)	Antenna Polarity	Remark
31.9400	21.68	30	−8.32	203	361	Vertical	Peak detection
143.4900	17.49	30	−12.51	100	237	Vertical	Peak detection
359.8000	22.33	37	−14.67	100	157	Vertical	Peak detection
597.4500	26.28	37	−10.72	399	357	Vertical	Peak detection
776.9000	28.95	37	−8.05	199	0	Vertical	Peak detection
823.4600	29.54	37	−7.46	300	33	Vertical	Peak detection
30.0000	21.85	30	−8.15	200	320	Horizontal	Peak detection
330.7000	20.11	37	−16.89	101	213	Horizontal	Peak detection
551.1200	24.43	37	−12.57	400	327	Horizontal	Peak detection
680.8700	32.86	37	−4.14	101	287	Horizontal	Peak detection
680.9500	27.16	37	−9.84	101	275	Horizontal	Quasi peak
790.4800	29.98	37	−7.02	101	2	Horizontal	Peak detection
914.6400	29.97	37	−7.03	300	362	Horizontal	Peak detection

Table 12. CISPR 11 Radiated Emissions at Critical Frequencies, I_OUT = 20 mA
Frequency (MHz)	Result (dBμV)	Limit (dBμV)	Margin (dB)	Height (cm)	Degree (°)	Antenna Polarity	Remark
30.0000	22.93	30	−7.07	100	309	Vertical	Peak detection
348.1600	22.97	37	−14.03	100	135	Vertical	Peak detection
467.4700	23.96	37	−13.04	300	259	Vertical	Peak detection
649.8300	27.43	37	−9.57	200	84	Vertical	Peak detection
777.8700	29.40	37	−7.60	399	262	Vertical	Peak detection
923.3700	29.20	37	−7.80	100	251	Vertical	Peak detection
30.9700	21.34	30	−8.66	300	360	Horizontal	Peak detection
356.8900	21.49	37	−15.51	300	241	Horizontal	Peak detection
599.3900	26.73	37	−10.27	300	360	Horizontal	Peak detection
681.5000	27.93	37	−9.07	101	183	Horizontal	Quasi peak
683.7800	32.35	37	−4.65	101	243	Horizontal	Peak detection
821.5200	28.78	37	−8.22	101	191	Horizontal	Peak detection
889.4200	28.38	37	−8.62	400	221	Horizontal	Peak detection

Figure 59. CISPR 11 Test Setup Configuration Diagram

Figure 60. CISPR 11 Radiated Emission Test Setup Photograph

Figure 61. Radiated Emission Level vs. Frequency, Horizontal Antenna Polarization, V_OUT = 10 V

Figure 62. Radiated Emission Level vs. Frequency, Vertical Antenna Polarization, V_OUT = 10 V

Figure 63. Radiated Emission Level vs. Frequency, Horizontal Antenna Polarization, I_OUT = 20 mA

Figure 64. Radiated Emission Level vs. Frequency, Vertical Antenna Polarization, I_OUT = 20 mA

EMC BOARD SCHEMATICS AND ARTWORK

Figure 65. AD5758 and ADP1031 EMC Test Board Schematics, System Power Supply and USB Communication Port

Figure 66. AD5758 and ADP1031 EMC Test Board Schematics, MCU and Periphery Circuit

Figure 67. AD5758 and ADP1031 EMC Test Board Schematics, Field Power Supply and Digital Isolation

Figure 68. AD5758 and ADP1031 EMC Test Board Schematics, AD5758 Periphery Circuit

ORDERING INFORMATION

BILL OF MATERIALS

Table 13.
Reference Designator	Part Description	Part Number	Manufacturer
C1, C2, C13, C17	Capacitor, ceramic, C0G (NP0), general-purpose, 20 pF	GRM1885C1H200JA01D	Murata
C3 to C7, C10, C14 to C16, C21, C23, C27 to C29, C32, C33, C35, C46, C52, C55, C64, C68, C80, C81, C117, C119 to C121, C128, C141	Capacitor, ceramic, X7R, 0603, 0.1 μF	06035C104KAT2A	AVX
C175,C176,C177	Capacitor, ceramic, X7R, general-purpose, 0.01 μF	GRM155R71E103KA01D	Murata
C178	Capacitor, ceramic, NP0, general-purpose, 22 pF	CC0402JRNPO9BN220	YAGEO
C122	Multilayer ceramic capacitor (MLCC) for high voltage, X7R, 3300 pF	HV1812Y332KXHATHV	Vishay
C9,C11	Capacitor, ceramic, X5R, general-purpose, 10 μF	GRM31CR61H106KA12L	Murata
C22, C24, C25, C30,C31, C45, C82, C118	MLCC, X5R, 4.7 μF	C2012X5R1H475K125AB	TDK
C8, C12	Capacitor, ceramic, 8.2 pF	06035A8R2CAT2A	AVX
C39, C125	Capacitor, ceramic, X7R, high voltage, 0.001 μF	C1812C102KHRACTU	Kemet
C130	Capacitor, ceramic, X7R, soft termination, 0.01 μF	C1608X7R1H103K080AE	TDK
C53, C131, C133, C138, C142 to C144	Capacitor, ceramic, X7R, 0.01 μF	GCM155R71H103KA55D	Murata
C18, C19	Capacitor, ceramic, X7R, 0.47 μF	C1608X7R1H474MT	TDK
C26	MLCC, X5R, 10 μF	C2012X5R1V106K085AC	TDK
C34	Capacitor, ceramic, X7R, 2.2 μF	UMK212BB7225KG-T	Taiyo Yuden
C37, C44, C47 to C49, C54	Capacitor, ceramic, X7R, general-purpose, 2.2 μF	GRM31CR71H225KA88L	Murata
C38	Capacitor, ceramic, NP0, 220 pF	CC0603JRNPO9BN221	Yageo
C40, C41, C95, C96	Capacitor, ceramic, NP0, 0.001 μF	12065A102JAT2A	AVX
C50	Capacitor, ceramic, C0G (NP0), general-purpose, 0.002 μF	GRM2165C1H202JA01D	Murata
C56, C57	Capacitor, ceramic, X7R, general-purpose, 0.01 μF	GCG188R71H103KA01D	Murata
C62	Capacitor, ceramic, X5R, general-purpose, 4.7 μF	GRM21BR61E475KA12L	Murata
C63	Capacitor, ceramic, X7R, 1 μF	0603YC105KAT2A	AVX
D4, D10	Diode, general-purpose, rectifier	S2M	ON Semiconductor
D5, D6, D11, D12	Diode, TVS, bidirectional	SMCJ33CA-TR	ST Microelectronics
D16	Diode, TVS, bidirectional	SMAJ33CA-TR	ST Microelectronics
D2	Diode, Schottky Rectifier	BAT46W-7-F	Diodes Incorporated
DS1, DS2, DS5, DS6	LED, SMD, 0603,green	SML-LX0603GW-TR	Lumex
DS3, DS4, DS7	LED, SMD, 0603, red	TLMS1100-GS08	Vishay
E1, E2, E3, E4	Inductor, ferrite bead, 1 .5kΩ, 100 MHz	BLM18HE152SN1D	Murata
E5, R68, R166, R167	Resistor, thick film, chip, 1210, 0 Ω	CRCW12100000Z0EAHP	Vishay
FL1	Filter, EMI, common-mode, 30 dB, 0.1 A, 8 Ω	EMI2121MTTAG	ON Semiconductor
JP25, JP26	Connector, PCB, header jumper, 1 × M000385	22-03-2031	Molex
L1, L6, L8	Ferrite bead ,SMD, 120 Ω, 120 nH	LI0805H750R-10	Laird
L2, L3	Inductor, power choke, 100 μH	LPS5030-104MRB	Coilcrft
L5	Inductor, shielded power, 47 μH	LPS4018-473MRB	Coilcraft
P1	Connector, PCB, header, low profile	5103308-5	TE Connectivity LTD
P2, P14	Connector, PCB, terminal block, two position, green	1727010	Phoenix Contact
P3	Connector, PCB, receptor, mini USB 2.0	UX60SC-MB-5S8	Hirose
P4	Connector, PCB, four position terminal block, single-row, straight, 2.54 mm pitch, 3.5 mm tail length	1725672	Phoenix Contact
P8, R1, R2, R14, R16 to R18, R60, R164, R170, R173	Resistor, thick film, chip, 0603, 0 Ω	MC0603WG00000T5E-TC	Multicomp
R9, R10, R36, R37, R143, R152, R154 R155	Resistor, thick film, chip, 0603, 10 kΩ	MC0100W0603110K	Multicomp
R19 to R21, R23, R24, R27 to R32, R47 to R54, R62 to R65	Resistor, thick film, chip, 0603, 100 Ω	MC0.063W06031100R	Multicomp
R3, R4, R11, R33, R61, R76, R77	Resistor, thick film, chip, 0603, 499 Ω	ERJ-3EKF4990V	Panasonic
R5 to R8, R12, R22, R25, R26, R34, R35, R38, R40 to R42, R66, R67, R74, R75, R141, R151, R163, R168, R171, R182	Resistor, thick film, chip, 0603, 100 kΩ	ERJ-3EKF1003V	Panasonic
R138	Resistor, thick film, chip, 0603, 1 MΩ	ERJ-3EKF1004V	Panasonic
R139	Resistor, thick film, chip, 0603, 210 kΩ	ERJ-3EKF2103V	Panasonic
R89	Resistor, thick film, chip, 0402, 0 Ω	MC00625W040210R	Multicomp
R13, R15, R92 to R94, R140, R142, R148	Resistor, thick film, chip, 0603, 33 Ω	MC0.063W0603133R	Multicomp
R43	Resistor, thick film chip, 0603, 31.6 kΩ	ERJ-3EKF3162V	Panasonic
R44, R46	Resistor, thick film, chip, 0603, 560 kΩ	MC 0.063W 0603 1% 560K	Multicomp
R45	Resistor, thick film, chip, 0603, 23.2 kΩ	ERJ-3EKF2322V	Panasonic
R56, R145	Resistor, thick film, chip, 0603, 1 kΩ	MC0063W060311K	Multicomp
R176, R177	Resistor, thin film, chip, 0805, 0 Ω	MC0.1W08050R	Multicomp
R180, R181	Resistor, thick film, chip, 0603, 2 kΩ	MC0.063W060312K	Multicomp
R55	Resistor, precision, thin film, 0603, 13.7 kΩ	RN73C1J13K7BTG	TE Connectivity
R57	Resistor, thick film, chip, 0805, 10 Ω	ERJ-6ENF10R0V	Panasonic
R58	Resistor, thick film, high voltage, chip, 4.7 MΩ	CHV2010-JW-475ELF	Bourns
S1 to S4	Switch, surface mount, SMT	B3S1000	Omron
T1, T3	Common-mode choke, DLW5BS series, 190 Ω, 5 A	DLW5BSN191SQ2L	Murata
T2	Flyback transformer, 1:1 ratio, 280 μH, 250 mA	750316743	Würth Elektronik
U1	IC, ultra low power, Arm Cortex-M3, MCU	ADuCM3029BCPZ	Analog Devices
U11	IC, micropower, precision, series mode, voltage reference	AD1582ARTZ	Analog Devices
U13	IC, TTL, single, two input positive and gate	SN74LVC1G08DBVT	Texas Instruments
U2	IC, 3 V, 128 Mb, serial flash memory with dual/quad SPI and quick path interconnect (QPI)	W25Q128FVSIG	Winbond
U26	IC, TTL, single, two-input, positive and gate	SN74AHCT1G08DCKR	Texas Instruments
U3	IC, isolated micro power management unit and digital isolator, adjustable V_OUT1, 5.15 V V_OUT2, adjustable V_OUT3	ADP1031ACPZ-1-R7	Analog Devices
U4	IC, single-channel, 16-bit, current/voltage output DAC, dynamic power control, HART connectivity	AD5758BCPZ-REEL	Analog Devices
U6	IC, low noise, CMOS, LDO regulator, 5 V voltage output	ADP7142ARDZ-5.0	Analog Devices
U7	IC, USB, serial universal asynchronous receiver/transmitter (UART)	FT232RQ	FTDI
U8	IC, low quiescent current, CMOS linear regulator, 3.0 V voltage output	ADP124ARHZ-3.0-R7	Analog Devices
U9	IC, micropower voltage reference, 2.5 V voltage output	ADR3425ARJZ-R7	Analog Devices
Y1	IC, crystal, SMD, 12.5 pF, 32.7680 kHz	MC-306-32.7680K- A0:ROHS	Seiko
Y2	IC, crystal, ultraminiature ceramic sealed, 10 pF, 26.000 MHz	ABM8G-26.000MHZ- B4Y-T	Abracon