ACS720
High-accuracy Hall-effect current sensor with 4.8kV isolation, ±1% total error, and 120kHz bandwidth for precision cu...
Product Overview
Description
The ACS720 is a high-accuracy, Hall-effect current sensor designed for industrial and automotive applications requiring precise current measurement. The device features 4.8kV galvanic isolation between the current path and sensor circuitry, making it suitable for high-voltage applications up to 800V working voltage.
With ±1% total error at 25°C and 120kHz bandwidth, the ACS720 provides excellent accuracy and response time for motor control, power supply monitoring, and energy metering applications. The sensor is available in multiple current ranges from ±10A to ±40A, with sensitivity options of 200mV/A, 100mV/A, and 50mV/A.
The device features a ratiometric analog output centered at Vcc/2, enabling bidirectional current measurement. Integrated temperature compensation maintains accuracy across the automotive temperature range of -40°C to 150°C. The SOIC-16 package provides excellent thermal performance and easy PCB mounting.
Product Series
ACS
Primary Application
Motor control and drives
Key Features
- High accuracy ±1% total error
- 4.8kV RMS galvanic isolation
- Low resistance current conductor (0.85mΩ)
- 120kHz bandwidth for fast response
- Ratiometric analog output
- Bidirectional current measurement
- Integrated temperature compensation
- AEC-Q100 Grade 0 qualified
Specifications
| Current Range | ±10A, ±20A, ±40A |
|---|---|
| Sensitivity | 200, 100, 50 mV/A |
| Bandwidth | 120kHz typical |
| Isolation Voltage | 4.8kV RMS |
| Total Error | ±1% at 25°C |
| Response Time | 4μs typical |
| Supply Voltage | 3.3V or 5V |
| Output | Analog, ratiometric |
| Package | SOIC-16 |
| Temperature Range | -40°C to +150°C |
Applications
Motor control and drives
Motor drive and control systems
Power supply monitoring
Power conversion and supply
Energy metering systems
Renewable energy systems
Solar inverter monitoring
Renewable energy systems
EV charging stations
Battery and charging management
Industrial automation
Industrial automation and control
FAE Expert Insights
"The ACS720 is my preferred choice for applications requiring high accuracy and isolation. The ±1% total error is significantly better than the ACS712's ±1.5%, making it suitable for energy metering and precision motor control. The 4.8kV isolation provides excellent safety margin for 400V and 800V systems. I've successfully used it in solar inverter monitoring where accuracy directly impacts revenue calculations. The 120kHz bandwidth is adequate for most motor control applications, though not as fast as the ACS37610's 1MHz. The SOIC-16 package is larger than the ACS712's SOIC-8 but provides better thermal performance. Key advantages over ACS712: better accuracy, higher isolation, wider temperature range. The trade-off is slightly higher cost and larger package. For applications where accuracy matters, the ACS720 is worth the premium."
±1% accuracy excellent for metering; 4.8kV isolation for high-voltage systems; better thermal performance than ACS712
— Sarah Johnson, BeiLuo
Frequently Asked Questions
What is the accuracy advantage of ACS720 over ACS712?
The ACS720 provides ±1% total error at 25°C compared to ACS712's ±1.5%. This 0.5% improvement is significant for precision applications: Energy metering - 0.5% accuracy improvement directly impacts billing accuracy and revenue; Motor control - better torque control and efficiency optimization; Power monitoring - more accurate power calculations and load balancing. Over temperature, the ACS720 maintains ±2% error vs ACS712's ±3-4%, providing better stability in automotive and industrial environments. The improved accuracy comes from better Hall element design, advanced temperature compensation, and tighter factory calibration. For applications where accuracy is critical, the ACS720's premium is justified by performance gains.
Use ACS720 for ±1% accuracy requirements; ACS712 for cost-sensitive applications where ±1.5% is acceptable.
How does the 4.8kV isolation benefit high-voltage applications?
The ACS720's 4.8kV RMS isolation provides significant advantages for high-voltage applications: Safety margin - 4.8kV provides 6:1 safety margin for 800V EV systems (6× working voltage); Regulatory compliance - meets reinforced insulation requirements for touch-safe designs; Working voltage - supports up to 1600V working voltage for basic insulation, 800V for reinforced insulation; Transient protection - withstands voltage spikes and transients common in power electronics. Comparison to ACS712 (2.1kV): ACS720 supports higher working voltages; Meets stricter safety standards; Suitable for 800V EV systems; Better long-term reliability. Applications benefiting: EV battery management (400V/800V), solar inverters (1000V DC), motor drives (480V AC), industrial power supplies.
Use ACS720 for 400V-800V systems requiring 4.8kV isolation; ACS712 sufficient for < 400V applications.
What is the thermal performance of ACS720?
The ACS720 thermal performance characteristics: Conductor resistance - 0.85mΩ typical, generating P = I² × R heat; Temperature rise - depends on current and PCB thermal design; SOIC-16 package - larger than SOIC-8, providing better heat dissipation. Thermal calculations: At 20A: P = 400 × 0.00085 = 0.34W; At 40A: P = 1600 × 0.00085 = 1.36W. With typical θja of 40°C/W for SOIC-16 on standard PCB: At 20A: ΔT = 0.34 × 40 = 13.6°C; At 40A: ΔT = 1.36 × 40 = 54.4°C. Thermal design recommendations: Use large copper areas (≥ 1 oz, ≥ 100mm²) for heat spreading; Add thermal vias to inner layers; Consider forced air cooling for continuous high-current operation; Monitor junction temperature to stay below 150°C. The ACS720's better thermal performance vs ACS712 enables higher continuous current operation.
Use adequate copper area for heat dissipation; monitor temperature at max current; consider forced air for continuous operation.
How do I select the right current range for ACS720?
ACS720 current range selection guidelines: Available ranges - ±10A (200mV/A), ±20A (100mV/A), ±40A (50mV/A). Selection criteria: Maximum current - choose range 1.5-2× maximum expected current; Resolution - lower current ranges provide better resolution (mA/bit); Accuracy - all ranges have ±1% total error; Bandwidth - 120kHz for all ranges. Examples: 5A motor - select ±10A range for best resolution; 15A power supply - select ±20A range with margin; 30A inverter - select ±40A range. Resolution comparison at 12-bit ADC (5V): ±10A: 20A/4096 = 4.9mA resolution; ±20A: 40A/4096 = 9.8mA resolution; ±40A: 80A/4096 = 19.5mA resolution. Trade-offs: Smaller range = better resolution but less headroom; Larger range = more headroom but lower resolution. For dynamic loads, ensure peak currents stay within range.
Select range 1.5-2× max current; use ±10A for best resolution; ±40A for high-current applications.
What applications benefit most from ACS720's features?
Applications benefiting from ACS720's high accuracy and isolation: Energy metering - ±1% accuracy meets revenue-grade requirements; precise power measurement for billing; Solar inverters - 4.8kV isolation for 1000V DC systems; accurate MPPT power monitoring; Motor control - precise torque control with ±1% accuracy; fast overcurrent protection; EV charging - isolated sensing for 400V/800V systems; accurate charge monitoring; Industrial drives - robust operation in noisy environments; accurate power monitoring; Power supplies - precise current limiting and monitoring; feedback for control loops. The combination of accuracy, isolation, and bandwidth makes ACS720 ideal for applications where measurement precision directly impacts system performance or revenue. The AEC-Q100 qualification also makes it suitable for automotive applications.
Use ACS720 for metering, solar, motor control, EV charging where accuracy and isolation are critical.