Part A
ACS722LLCTR-20AU-T
Allegro MicroSystems
- Lifecycle
- Active
- Stock
- 6271 PCS
- Package
- SOIC-N-8
- Series
- Current Sensors
Replacement verdict
Not a drop-in replacement
The ACS722LLCTR-05AB-T and ACS722LLCTR-20AU-T are not functionally interchangeable despite sharing the ACS722 family platform. The 05AB variant provides a bidirectional ±5 A sensing range with analog output, while the 20AU variant offers a unidirectional 0 to 20 A sensing range with analog output. The differing current sensing ranges, directionality, and sensitivity characteristics make direct substitution impractical without circuit redesign and recalibration.
Different current sensing range
Different directionality
Different sensitivity
Recalibration required
Parts at a glance
Part B
ACS722LLCTR-05AB-T
Allegro MicroSystems
- Lifecycle
- Active
- Stock
- 7660 PCS
- Package
- SOIC-N-8
- Series
- Current Sensors
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ACS722LLCTR-05AB-T | ACS722LLCTR-20AU-T | Why it matters |
|---|---|---|---|
| Current Sensing Range | ±5 A | ±20 A | Defines the maximum measurable current; a ±5 A sensor cannot directly replace a ±20 A sensor in higher-current applications without saturating. |
| Sensitivity | 264 mV/A | 66 mV/A | Determines output voltage per amp of sensed current; different sensitivity changes the ADC scaling and resolution of the measurement. |
| Output Type | Bidirectional | Unidirectional | Bidirectional parts measure both positive and negative current, while unidirectional parts only measure one polarity, affecting circuit topology and signal interpretation. |
| Supply Voltage | 3.0 V to 3.6 V | 3.0 V to 3.6 V | Both require a 3.3 V nominal rail; supply compatibility is essential for direct drop-in substitution. |
| Isolation Voltage | 2400 Vrms | 2400 Vrms | Galvanic isolation rating must meet the safety requirements of the application; identical ratings allow equivalent high-voltage protection. |
| Bandwidth | 80 kHz | 80 kHz | Determines the maximum signal frequency the sensor can accurately track; matching bandwidth preserves dynamic response. |
| Package | SOIC-8 | SOIC-8 | Footprint and pinout must match for a physical drop-in replacement on the PCB. |
| Operating Temperature Range | -40 °C to 150 °C | -40 °C to 150 °C | Thermal range must cover the application environment to ensure reliable operation and accuracy. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ACS722LLCTR-20AU-T | ACS722LLCTR-05AB-T |
|---|---|---|
| Part Status | Active | Active |
| For Measuring | DC | AC/DC |
| Sensor Type | Hall Effect, Open Loop | Hall Effect, Open Loop |
| Current - Sensing | 20A | 5A |
| Number of Channels | 1 | 1 |
| Output | Ratiometric, Voltage | Ratiometric, Voltage |
| Sensitivity | 132mV/A | 264mV/A |
| Frequency | DC ~ 80kHz | DC ~ 80kHz |
| Linearity | ±1% | ±1% |
| Accuracy | ±3% | ±3% |
| Voltage - Supply | 3V ~ 3.6V | 3V ~ 3.6V |
| Response Time | 5µs | 5µs |
| Current - Supply (Max) | 12mA | 12mA |
| Operating Temperature | -40°C ~ 150°C | -40°C ~ 150°C |
| Polarization | Unidirectional | Bidirectional |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the ACS722LLCTR-05AB-T and ACS722LLCTR-20AU-T?
The ACS722LLCTR-05AB-T is a bidirectional current sensor with a ±5 A sensing range and an analog output, while the ACS722LLCTR-20AU-T is a unidirectional current sensor with a 20 A sensing range and an analog output. Both are galvanically isolated Hall-effect sensors in the same SOIC-8 package.
Are the ACS722LLCTR-05AB-T and ACS722LLCTR-20AU-T pin-compatible?
Yes. Both devices are offered in the same 8-lead SOIC package with identical pinouts, allowing them to share the same PCB footprint. However, external component values and output signal conditioning may differ due to different sensitivity and measurement ranges.
What is the sensitivity of each device?
The ACS722LLCTR-05AB-T has a typical sensitivity of 264 mV/A. The ACS722LLCTR-20AU-T has a typical sensitivity of 66 mV/A. These values are specified in the Allegro MicroSystems datasheet for the ACS722 family.
Can the ACS722LLCTR-05AB-T and ACS722LLCTR-20AU-T measure both AC and DC currents?
Yes. Both devices are Hall-effect current sensors capable of measuring AC and DC currents. The ACS722LLCTR-05AB-T is bidirectional, meaning it can measure current flowing in both directions, while the ACS722LLCTR-20AU-T is unidirectional and measures current in one direction only.
What is the supply voltage requirement for these devices?
Both the ACS722LLCTR-05AB-T and ACS722LLCTR-20AU-T operate from a single 3.3 V supply. The datasheet specifies a supply voltage range of 3.0 V to 3.6 V for the ACS722 family.
What is the isolation voltage rating for these current sensors?
Both devices provide galvanic isolation between the current-carrying conductor and the low-voltage signal side. The ACS722 family is rated for a dielectric strength of 2.4 kVRMS for 1 minute, per the Allegro MicroSystems datasheet.
Which device is better for low-current measurement applications?
The ACS722LLCTR-05AB-T is better suited for low-current measurement because its ±5 A range and higher sensitivity of 264 mV/A provide finer resolution for small currents. The ACS722LLCTR-20AU-T, with its 20 A range and 66 mV/A sensitivity, is optimized for higher-current unidirectional applications.
Are these devices qualified for automotive applications?
The ACS722LLCTR-05AB-T and ACS722LLCTR-20AU-T are not automotive-qualified parts. They are industrial-grade sensors. For automotive-grade equivalents, refer to the ACS722xLxATR series or other AEC-Q100 qualified devices from Allegro MicroSystems.