ACS37800
Isolated, Digital Output, Power Monitoring IC
with Zero-Crossing Detection, Overcurrent and Overvoltage Flagging
DESCRIPTION
FEATURES AND BENEFITS
• Accurate power monitoring for AC and DC applications
• UL 60950-1 (ed. 2) and UL 62368-1 (ed. 1) certified for
reinforced isolation up to 517 VRMS in a single package
• Accurate measurements of active, reactive, and apparent
power, as well as power factor
• Separate RMS and instantaneous measurements for both
voltage and current channels
• Two programmable averaging blocks
TheAllegroACS37800powermonitoringICgreatlysimplifies
the addition of power monitoring to manyAC or DC powered
systems. The sensor may be powered from the same supply
as the system’s MCU, eliminating the need for multiple
power supplies. The device’s construction includes a copper
conduction path that generates a magnetic field proportional
to applied current. The magnetic field is sensed differentially
to reject errors introduced by common mode fields.
• 0.85 mΩ primary conductor resistance for low power loss
and high inrush current withstand capability
• Compatible with floating and non-floating GND
• Dedicated voltage or current zero crossing pin
• Fast, user-programmable overcurrent fault pin (5 µs typ.)
• User-programmable undervoltage and overvoltage RMS
thresholds
• 1 kHz bandwidth
• Current sensing range up to 90 A
• Options for I2C or SPI digital interface protocols
Allegro’s Hall-effect-based, galvanically isolated current
sensing technology achieves reinforced isolation ratings
(4800 VRMS) in a small PCB footprint. These features enable
isolated current sensing without expensive Rogowski coils,
oversizedcurrenttransformers,isolatedoperationalamplifiers,
or the power loss of shunt resistors.
The ACS37800 power monitoring IC offers key power
measurement parameters that can easily be accessed through
its SPI or I2C digital protocol interfaces. Dedicated and
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
of the IC is available through on-chip EEPROM.
PACKAGE
16-pin SOICW (suffix MA)
The ACS37800 is provided in a small low-profile surface
mountSOIC16wide-bodypackage,islead(Pb)free,andisfully
calibrated prior to shipment from theAllegro factory. Customer
calibration can further increase accuracy in application.
Not to scale
REINFORCED
ISOLATION
N (L)
L (N)
1 MΩ 1 MΩ
MCU
RSENSE
1 MΩ 1 MΩ
GND
1
16
VCC
VINP
VINN
IP+ ACS37800
I2C
Only
2
3
15
14
13
12
11
10
9
IP+
IP+
IP+
IP-
IP-
IP-
IP-
RPULLUP
GND
To User
4
5
6
7
8
VCC
IP
RPULLUP
SDA / MISO
SCL / SCLK
DIO_0 / MOSI
DIO_1 / CS
CB Certificate Number:
US-32210-M1-UL
US-36315-UL
Linear
Regulator
Single Output
Isolated Power
Supply
(Flyꢀack, etc.)
Figure 1: Typical Application
ACS37800-DS
MCO-0001004
November 30, 2020