Datasheet ACS37800 (Allegro)

ACS37800 Isolated, Digital Output, Power Monitoring IC with Zero-Crossing Detection, Overcurrent and Overvoltage Flagging FEATURES AND BENEFITS DESCRIPTION
• Accurate power monitoring for AC and DC applications The Allegro ACS37800 power monitoring IC greatly simplifies • UL 60950-1 (ed. 2) and UL 62368-1 (ed. 1) certified for the addition of power monitoring to many AC or DC powered reinforced isolation up to 517 VRMS in a single package systems. The sensor may be powered from the same supply • Accurate measurements of active, reactive, and apparent as the system’s MCU, eliminating the need for multiple power, as well as power factor power supplies. The device’s construction includes a copper • Separate RMS and instantaneous measurements for both conduction path that generates a magnetic field proportional voltage and current channels to applied current. The magnetic field is sensed differentially • Two programmable averaging blocks to reject errors introduced by common mode fields. • 0.85 mΩ primary conductor resistance for low power loss Allegro’s Hall-effect-based, galvanically isolated current and high inrush current withstand capability sensing technology achieves reinforced isolation ratings • Compatible with floating and non-floating GND (4800 VRMS) in a small PCB footprint. These features enable • Dedicated voltage or current zero crossing pin isolated current sensing without expensive Rogowski coils, • Fast, user-programmable overcurrent fault pin (5 µs typ.) oversized current transformers, isolated operational amplifiers, • User-programmable undervoltage and overvoltage RMS or the power loss of shunt resistors. thresholds The ACS37800 power monitoring IC offers key power • 1 kHz bandwidth measurement parameters that can easily be accessed through • Current sensing range up to 90 A its SPI or I2C digital protocol interfaces. Dedicated and • Options for I2C or SPI digital interface protocols configurable I/O pins for voltage/current zero crossing, undervoltage and overvoltage reporting, and fast overcurrent fault detection are available in I2C mode. User configuration
PACKAGE
of the IC is available through on-chip EEPROM. 16-pin SOICW (suffix MA) The ACS37800 is provided in a small low-profile surface mount SOIC16 wide-body package, is lead (Pb) free, and is fully calibrated prior to shipment from the Allegro factory. Customer calibration can further increase accuracy in application. Not to scale
REINFORCED L (N) N (L) ISOLATION
1 MΩ 1 MΩ R
MCU
1 MΩ 1 MΩ SENSE GND 1 16 VCC IP+
ACS37800
VINP 2 15
I2C
IP+ VINN
Only
R 3 14 PULLUP IP+ GND
To User
4 13 IP+ VCC IP 5 12 IP- SDA / MISO RPULLUP 6 11 IP- SCL / SCLK 7 10 IP- DIO_0 / MOSI
CB Certificate Number:
8 9 IP- DIO_1 / CS
US-32210-M1-UL US-36315-UL Linear Single Output Regulator Isolated Power Supply (Flybac , k etc.) Figure 1: Typical Application
ACS37800-DS November 30, 2020 MCO-0001004 Document Outline Features and Benefits Description Package Typical Application Selection Guide Absolute Maximum Ratings Isolation Characteristics ESD Ratings Thermal Characteristics Functional Block Diagram Pinout Diagram and Terminal List Electrical Characteristics 15B5 Performance Characteristics 30B3 Performance Characteristics 90B3 Performance Characteristics I2C Operating Characteristics SPI Operating Characteristics Theory of Operation Introduction Voltage and Current Measurements Overcurrent Measurement Path Trim Methods Power Calculations Operational Block Diagram Configurable Settings Configuring the DIO Pins (I2C Devices) Configuring the Device for AC Applications Device EEPROM Settings Voltage Measurement Current Measurement Configuring the Device for DC Applications Device EEPROM Settings Voltage Measurement Current Measurement RMS and Power Accuracy vs. Operation Point RMS and Power Output Error vs. Applied Input 15B5 IRMS and Power Error 30B3 IRMS and Power Error 90B3 IRMS and Power Error Digital Communication Communication Interfaces SPI Registers and EEPROM EEPROM Error Checking and Correction (ECC) I2C Slave Adressing EEPROM/Shadow Memory Map Register Details – EEPROM Volatile Memory Map Register Details - Volatile Application Information Thermal Rise vs. Primary Current ASEK37800 Evaluation Board Layout Recommended PCB Layout Package Outline Drawing