NSSolarMagicSM73201DCArc reference design

/a>Solar” title=”Solar”>Solar” title=”Solar”>Solar cells PV DC Arc detection system, sensor interface, I/O Modules, solar data acquisition, motor control and instrumentation and control system. This article introduces SM73201 main features, block diagram and typical application circuit diagram, and low power and low cost data acquisition system block diagram, SolarMagic SM73201 DC Arc detection evaluation board main features, block diagram, analog front end and bill of materials (BOM).

SM73201: 16-Bit, 50 to 250 kSPS, Differential Input, MicroPower ADC

The SM73201 is a 16-bit successive-approximation register (SAR) Analog-to-Digital converter (ADC) with a maximum sampling rate of 250 kSPS. The SM73201 has a minimum signal span accuracy of ± 0.003% over the temperate range of − 40℃ to +85℃. The converter features a differential analog input with an excellent common-mode signal rejection ratio of 85 dB, making the SM73201 suitable for noisy environments.

The SM73201 operates with a single analog supply (VA) and a separate digital input/output (VIO) supply. VA can range from +4.5V to +5.5V and VIO can range from +2.7V to +5.5V. This allows a system designer to maximize performance and minimize power consumption by operating the analog portion of the ADC at a VA of +5V while interfacing with a +3.3V controller.

The serial data output is binary 2’s complement and is SPI™ compatible.

The performance of the SM73201 is guaranteed over temperature at clock rates of 1 MHz to 5 MHz and reference voltages of +2.5V to +5.5V. The SM73201 is available in a small 10-lead MSOP package. The high accuracy, differential input, low power consumption, and small size make the SM73201 ideal for direct connection to bridge sensors and transducers in battery operated systems or remote data acquisition applications.

Main features of SM73201:

■ Renewable Energy Grade

■ Guaranteed performance from 50 to 250 kSPS

■ ±0.003% signal span accuracy

■ Separate Digital Input/Output Supply

■ True differential input

■ External voltage reference range of +0.5V to VA

■ Wide input common-mode voltage range of 0V to VA

■ SPI™/QSPI™/MICROWIRE™ compatible Serial Interface

■ Operating temperature range of −40℃ to +85℃

■ Small MSOP-10 package

SM73201 main indicators:

■ Conversion Rate 50 kSPS to 250 kSPS

■ Offset Error Temp Drift 2.5 μV/℃

■ Gain Error Temp Drift 0.3 ppm/℃

■ SNR 93.2 dBc

■ THD − 104 dBc

■ Power Consumption

■ — 200 kSPS, 5V 5.3 mW

— 250kSPS, 5V 5.8mW

— Power-Down, 5V 10 μW

SM73201 application:

■ PV DC Arc Detect System

■ Direct Sensor Interface

■ I/O Modules

■ Solar Data Acquisition

■ Motor Control

■ Instrumentation and Control Systems
NSSolarMagicSM73201DCArc reference design
figure 1. SM73201 block diagram
NSSolarMagicSM73201DCArc reference design
figure 2. SM73201 Typical Application Circuit Diagram
NSSolarMagicSM73201DCArc reference design
image 3. SM73201 low-power and low-cost data acquisition system block diagram

SolarMagic Reference Design RD-195: SolarMagic SM73201 DC Arc Detection Evaluation Board

The SolarMagic™ reference design kit RD-195 includes the SM73201-ARC-EV PCB which is a UL1699B compliant Photo-Voltaic Arc Detect System with a minimal footprint of less than 50 mm x 30 mm. The reference design utilizes National semiconductor`s advanced Analog technology along with an innovative dynamic filtering technique to effectively detect the signature of Arcing conductors in the presence of highly noisy real world environments. Implemented with National Semiconductor`s PowerWise® technology, the Analog path requires less than 50 mW of power to implement the active filtering. The operation range of the device covers the industrial temperature range of -40℃ to +125℃.

SolarMagic™ technology is an overall solution that works in existing and new installations, residential, commercial, and utility scale projects. National Semiconductor`s 50 years of experience in the electronics industry delivers unsurpassed manufacturing, design, and development technology.

NSSolarMagicSM73201DCArc reference design

Figure 4. SolarMagic SM73201 DC Arc Detection Evaluation Board Outline Drawing

Main features:

• 1,000V isolation

• Maximum DC string current=15A

• Simple LED arc detection flag

• Industrial Temperature Range (-40℃ to +125℃)

• Small PCB footprint of less than 50mm x 30mm.

• Low power requirement <400mW
NSSolarMagicSM73201DCArc reference design
Figure 5. SolarMagic SM73201 DC Arc Inspection and Evaluation System Block Diagram
NSSolarMagicSM73201DCArc reference design
Image 6.Analog front end
NSSolarMagicSM73201DCArc reference design
Figure 7. A/D converter
SolarMagic SM73201 DC Arc Detection Evaluation Board Bill of Materials:
NSSolarMagicSM73201DCArc reference design
NSSolarMagicSM73201DCArc reference design
For details, see:
http://www.national.com/ds/SM/SM73201.pdf
and
http://www.national.com/an/AN/AN-2154.pdf

The Links:   LB104S01(TL)(02) LM32019T