# ACS72981LLRATR-050U3 Current Sensor Compact Carrier 0A to 50A, 3.3V **Type:** Product page · **SKU:** POLOLU-5252 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia) **Page:** https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-compact-carrier-0a-to-50a-33v.html ([markdown](https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-compact-carrier-0a-to-50a-33v.html.md)) This board is a simple compact carrier of Allegro’s ACS72981LLRATR-050U3 Hall effect-based linear current sensor, which offers a low-resistance (~0.2 mO)... ## Pricing - **Price:** $23.05 (inc GST) — $20.95 AUD, exc GST - **Quantity discounts:** 10+ $20.12 (exc GST) · 25+ $19.49 (exc GST) ## Availability & dispatch - Available with a lead time — expect dispatch between Aug 28 and Aug 31. ## Description | [![](https://core-electronics.com.au/attachments/localcontent/0J12576_86315efa4c.jpg)](https://core-electronics.com.au/category/317/acs72981-current-sensor-large-carriers) **Large Carrier** | [\#5270](https://core-electronics.com.au/acs72981llratr-050b3-current-sensor-large-carrier-50a-to-50a-33v.html) | 050B3 | 3.0 to 3.6 (3.3 nominal) | Bidirectional | [±50 A](https://core-electronics.com.au/acs72981llratr-050b3-current-sensor-large-carrier-50a-to-50a-33v.html) | 26.4 | 1.65 | 1.4"×1.2" | |---|---|---|---|---|---|---|---|---| | [\#5273](https://core-electronics.com.au/acs72981llratr-100b3-current-sensor-large-carrier-100a-to-100a-33v.html) | 100B3 | [±100 A](https://core-electronics.com.au/acs72981llratr-100b3-current-sensor-large-carrier-100a-to-100a-33v.html) | 13.2 | | [\#5277](https://core-electronics.com.au/acs72981klratr-150b3-current-sensor-large-carrier-150a-to-150a-33v.html) | 150B3 | [±150 A](https://core-electronics.com.au/acs72981klratr-150b3-current-sensor-large-carrier-150a-to-150a-33v.html) | 8.8 | | [\#5272](https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-large-carrier-0a-to-50a-33v.html) | 050U3 | Unidirectional | [0-50 A](https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-large-carrier-0a-to-50a-33v.html) | 52.8 | 0.33 | | [\#5275](https://core-electronics.com.au/acs72981llratr-100u3-current-sensor-large-carrier-0a-to-100a-33v.html) | 100U3 | [0-100 A](https://core-electronics.com.au/acs72981llratr-100u3-current-sensor-large-carrier-0a-to-100a-33v.html) | 26.4 | | [\#5279](https://core-electronics.com.au/acs72981klratr-150u3-current-sensor-large-carrier-0a-to-150a-33v.html) | 150U3 | [0-150 A](https://core-electronics.com.au/acs72981klratr-150u3-current-sensor-large-carrier-0a-to-150a-33v.html) | 17.6 | | [\#5283](https://core-electronics.com.au/acs72981-current-sensor-large-carrier-200a-3-3v-pololu.html) | 200U3 | [0-200 A](https://core-electronics.com.au/acs72981-current-sensor-large-carrier-200a-3-3v-pololu.html) | 13.2 | | [\#5271](https://core-electronics.com.au/acs72981llratr-050b5-current-sensor-large-carrier-50a-to-50a-5v.html) | 050B5 | 4.5 to 5.5 (5 nominal) | Bidirectional | [±50 A](https://core-electronics.com.au/acs72981llratr-050b5-current-sensor-large-carrier-50a-to-50a-5v.html) | 40 | 2.5 | | [\#5274](https://core-electronics.com.au/acs72981llratr-100b5-current-sensor-large-carrier-100a-to-100a-5v.html) | 100B5 | [±100 A](https://core-electronics.com.au/acs72981llratr-100b5-current-sensor-large-carrier-100a-to-100a-5v.html) | 20 | | [\#5278](https://core-electronics.com.au/acs72981klratr-150b5-current-sensor-large-carrier-150a-to-150a-5v.html) | 150B5 | [±150 A](https://core-electronics.com.au/acs72981klratr-150b5-current-sensor-large-carrier-150a-to-150a-5v.html) | 13.3 | | [\#5282](https://core-electronics.com.au/acs72981elratr-200b5-current-sensor-large-carrier-200a-5v.html) | 200B5 | [±200 A](https://core-electronics.com.au/acs72981elratr-200b5-current-sensor-large-carrier-200a-5v.html) | 10 | | [\#5276](https://core-electronics.com.au/acs72981llratr-100u5-current-sensor-large-carrier-0a-to-100a-5v.html) | 100U5 | Unidirectional | [0-100 A](https://core-electronics.com.au/acs72981llratr-100u5-current-sensor-large-carrier-0a-to-100a-5v.html) | 40 | 0.5 | | [\#5280](https://core-electronics.com.au/acs72981klratr-150u5-current-sensor-large-carrier-0a-150a-5v.html) | 150U5 | [0-150 A](https://core-electronics.com.au/acs72981klratr-150u5-current-sensor-large-carrier-0a-150a-5v.html) | 26.7 | | | | [![](https://core-electronics.com.au/attachments/localcontent/0J12530_45558408d8.jpg)](https://core-electronics.com.au/category/316/acs72981-current-sensor-compact-carriers) **Compact Carrier** | [\#5250](https://core-electronics.com.au/acs72981llratr-050b3-current-sensor-compact-carrier-50a-to-50a-33v.html) | 050B3 | 3.0 to 3.6 (3.3 nominal) | Bidirectional | [±50 A](https://core-electronics.com.au/acs72981llratr-050b3-current-sensor-compact-carrier-50a-to-50a-33v.html) | 26.4 | 1.65 | 0.7"×0.8" | | [\#5253](https://core-electronics.com.au/acs72981llratr-100b3-current-sensor-compact-carrier-100a-to-100a-33v.html) | 100B3 | [±100 A](https://core-electronics.com.au/acs72981llratr-100b3-current-sensor-compact-carrier-100a-to-100a-33v.html) | 13.2 | | [\#5257](https://core-electronics.com.au/acs72981klratr-150b3-current-sensor-compact-carrier-150a-to-150a-33v.html) | 150B3 | [±150 A](https://core-electronics.com.au/acs72981klratr-150b3-current-sensor-compact-carrier-150a-to-150a-33v.html) | 8.8 | | [\#5252](https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-compact-carrier-0a-to-50a-33v.html) | 050U3 | Unidirectional | [0-50 A](https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-compact-carrier-0a-to-50a-33v.html) | 52.8 | 0.33 | | [\#5255](https://core-electronics.com.au/acs72981llratr-100u3-current-sensor-compact-carrier-0a-to-100a-33v.html) | 100U3 | [0-100 A](https://core-electronics.com.au/acs72981llratr-100u3-current-sensor-compact-carrier-0a-to-100a-33v.html) | 26.4 | | [\#5259](https://core-electronics.com.au/acs72981klratr-150u3-current-sensor-compact-carrier-0a-to-150a-33v.html) | 150U3 | [0-150 A](https://core-electronics.com.au/acs72981klratr-150u3-current-sensor-compact-carrier-0a-to-150a-33v.html) | 17.6 | | [\#5263](https://core-electronics.com.au/acs72981elratr-200u3-current-sensor-compact-carrier-0a-200a-3-3v.html) | 200U3 | [0-200 A](https://core-electronics.com.au/acs72981elratr-200u3-current-sensor-compact-carrier-0a-200a-3-3v.html) | 13.2 | | [\#5251](https://core-electronics.com.au/acs72981llratr-050b5-current-sensor-compact-carrier-50a-to-50a-5v.html) | 050B5 | 4.5 to 5.5 (5 nominal) | Bidirectional | [±50 A](https://core-electronics.com.au/acs72981llratr-050b5-current-sensor-compact-carrier-50a-to-50a-5v.html) | 40 | 2.5 | | [\#5254](https://core-electronics.com.au/acs72981llratr-100b5-current-sensor-compact-carrier-100a-to-100a-5v.html) | 100B5 | [±100 A](https://core-electronics.com.au/acs72981llratr-100b5-current-sensor-compact-carrier-100a-to-100a-5v.html) | 20 | | [\#5258](https://core-electronics.com.au/acs72981klratr-150b5-current-sensor-compact-carrier-150a-to-150a-5v.html) | 150B5 | [±150 A](https://core-electronics.com.au/acs72981klratr-150b5-current-sensor-compact-carrier-150a-to-150a-5v.html) | 13.3 | | [\#5262](https://core-electronics.com.au/acs72981elratr-200b5-current-sensor-compact-carrier-200a-5v.html) | 200B5 | [±200 A](https://core-electronics.com.au/acs72981elratr-200b5-current-sensor-compact-carrier-200a-5v.html) | 10 | | [\#5256](https://core-electronics.com.au/acs72981llratr-100u5-current-sensor-compact-carrier-0a-to-100a-5v.html) | 100U5 | Unidirectional | [0-100 A](https://core-electronics.com.au/acs72981llratr-100u5-current-sensor-compact-carrier-0a-to-100a-5v.html) | 40 | 0.5 | | [\#5260](https://core-electronics.com.au/acs72981klratr-150u5-current-sensor-compact-carrier-0a-to-150a-5v.html) | 150U5 | [0-150 A](https://core-electronics.com.au/acs72981klratr-150u5-current-sensor-compact-carrier-0a-to-150a-5v.html) | 26.7 | | \| [![](https://core-electronics.com.au/attachments/localcontent/0J12531_28646d11bc8.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12531_19899ed6388.jpg) \| \|---\| \| ACS72981LLRATR-050U3 Current Sensor Compact Carrier 0A to 50A, 3.3V, bottom view. \| | | |---|---| This compact carrier features the ACS72981LLRATR-050U3, which is intended for nominal 3.3 V operation and is designed for unidirectional input current from 0 A to 50 A. This version can be visually distinguished from the other versions by the “3V3 U05” printed on the bottom side, as shown in the left picture above. | Part Suffix | Range | Supply Voltage | Sensitivity @ 3.3 V | Zero Point @ 3.3 V | Size | |---|---|---|---|---|---| | 050U3 | 0-50 A (unidirectional) | 3.0 V to 3.6 V | 52.8 mV/A | 0.33 V | 0.7"×0.8" | A [**larger carrier**](https://core-electronics.com.au/acs72981llratr-050u3-current-sensor-large-carrier-0a-to-50a-33v.html) is also available for this sensor IC with room for larger connectors and thicker wires for the high-current path, offering different ways to use or evaluate this current sensor. **Using the sensor** | [![](https://core-electronics.com.au/attachments/localcontent/0J12518_311536d0612.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12518_17487176c8f.jpg) | |---| This sensor has five required connections: the input current (IP+ and IP-), logic power (VCC and GND), and the sensor output (VIOUT). The sensor requires a supply voltage of 3.0 V to 3.6 V to be connected across the VCC and GND pads, which are labeled on the bottom silkscreen. The sensor outputs a ratiometric analog voltage on VIOUT that has a zero point at VCC/10 and increases by 52.8 mV × (VCC/3.3 V) per amp of input current: VIOUT=VCC10+0.0528VA⋅VCC3.3V⋅IP=VCC⋅(110+IP62.5A)" role="presentation" style="position: relative;">VIOUT=VCC10+0.0528VA·VCC3.3V·IP=VCC·(110+IP62.5A)VIOUT=VCC10+0.0528VA·VCC3.3V·IP=VCC·(110+IP62.5A) IP=62.5A⋅(VIOUTVCC–110)" role="presentation" style="position: relative;">IP=62.5A·(VIOUTVCC–110)IP=62.5A·(VIOUTVCC–110) The VIOUT, VCC, and GND pins work with [0.1"-pitch header pins](https://core-electronics.com.au/0-100-2-54-mm-breakaway-male-header-1x40-pin-straight.html) and are compatible with standard [solderless breadboards](https://core-electronics.com.au/prototyping/breadboards.html). | [![](https://core-electronics.com.au/attachments/localcontent/0J12519_68700e628b5.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12519_27196d03a89.jpg) | |---| You can insert the board into your current path in a variety of ways. For typical high-current applications, you can solder wires directly to the through-holes that best match your wires, or you can use solderless ring terminal connectors, as shown in the pictures below. The largest through-holes are big enough for 8 AWG wires or #6 or M3.5 screws, and the second-largest through-holes (and mounting holes) are sized for 12 AWG wires or #2 or M2 screws. Holes with 0.1", 3.5 mm, and 5 mm spacing are also available as shown in the diagram above for connecting [male header pins](https://core-electronics.com.au/0-100-2-54-mm-breakaway-male-header-1x40-pin-straight.html) or [terminal blocks](https://core-electronics.com.au/category/117/terminal-blocks), but please note that these connection options will generally not be suitable for the kinds of high currents intended for this sensor. | \| [![](https://core-electronics.com.au/attachments/localcontent/0J12526_126413a226e.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12526_936389e71a4.jpg) \| \|---\| | \| [![](https://core-electronics.com.au/attachments/localcontent/0J12528_117568e3180.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12528_9435324ab90.jpg) \| \|---\|---\| | |---| | \| [![](https://core-electronics.com.au/attachments/localcontent/0J12527_11561a0f32e.jpg)![](https://core-electronics.com.au/attachments/localcontent/0J12529_1255667498b.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12527_977611b214f.jpg) \| | |---| **Warning:** This product is intended for use below 30 V. Working with higher voltages can be extremely dangerous and should only be attempted by qualified individuals with appropriate equipment and experience. **Schematic and dimension diagrams** | [![](https://core-electronics.com.au/attachments/localcontent/0J12524_30954eb6645.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12524_441167dbf8e.png) | |---| | ACS72981 Current Sensor Carrier schematic diagram. | The dimension diagram is available as a [**downloadable PDF**](https://core-electronics.com.au/attachments/localcontent/acs72981xlr-current-sensor-carriers_40046401b94.pdf) (400k pdf). **Real-world power dissipation considerations** | [![](https://core-electronics.com.au/attachments/localcontent/0J12693_10168035916.jpg)](https://core-electronics.com.au/attachments/localcontent/0J12693_16469d48f3f.jpg) | |---| | Thermal image of a high-current test of a Pololu current sensor carrier (not necessarily this product). | Depending on the version, the ACS72981 can measure up to ±200 A, but its datasheet specifies an absolute maximum continuous current of 120 A. Furthermore, the sensor chip can overheat at lower currents. In Pololu's tests, Pololu found that Pololu's ACS72981 carrier boards could conduct 60 A continuously while staying well below the thermal limit for the IC. Pololu's tests were conducted at approximately 25°C ambient temperature with no forced air flow. The actual current you can pass through the sensor will depend on how well you can keep it cool. The carrier’s printed circuit board is designed to help with this by drawing heat out of the sensor chip. Solid connections to the current path pins (such as with thick soldered wires or large, tightly-secured lugs) can also help reduce heat build-up in the sensor and carrier board. **Warning:** Exceeding temperature or current limits can cause **permanent damage** to the sensor. If you are measuring an average continuous current greater than 50 A, Pololu strongly recommend that you monitor the sensor’s temperature and look into additional cooling if necessary. This product can get **hot** enough to burn you long before the chip overheats. Take care when handling this product and other components connected to it. ### **Dimensions** | Size: | 0.7" × 0.8" | |---|---| | Weight: | 1.4 g | **General specifications** | Typical operating voltage: | 3.3 V | |---|---| | Current sense: | 52.8 mV/A[1](https://core-electronics.com.au/#note1) | | Minimum logic voltage: | 3.0 V | | Maximum logic voltage: | 3.6 V | | Supply current: | 14 mA[2](https://core-electronics.com.au/#note2) | | Current range: | 0A to ?50A (unidirectional 50A), 3.3V | | Current sensor: | Allegro ACS72981LLRATR-050U3 | **Notes:** **Identifying markings** | PCB dev codes: | cs04a | |---|---| | Other PCB markings: | 0J14752 | | Other PCB markings: | 3V3 U05 | **File downloads** - **[Dimension diagrams of the ACS72981xLR Current Sensor Carriers](https://core-electronics.com.au/attachments/localcontent/acs72981xlr-current-sensor-carriers_40046401b94.pdf) (400k pdf)** - **3D model of the ACS72981xLR Current Sensor Compact Carriers (3MB step)** - **Drill guide for the ACS72981xLR Current Sensor Compact Carriers (18k dxf)** This DXF drawing shows the locations of all of the board’s holes. **Recommended links** - **[ACS72981 datasheet](https://core-electronics.com.au/attachments/localcontent/acs72981-datasheet_398758c5124.pdf)** - **[Allegro Application Note AN296169: Characterizing System Bandwidth in Complex Current Sensor Applications](https://www.allegromicro.com/en/insights-and-innovations/technical-documents/hall-effect-sensor-ic-publications/an-effective-method-for-characterizing-system-bandwidth-an296169)** This is the application note referenced on page 16 of the ACS724 datasheet, page 22 of the ACS71240 datasheet, and page 42 of the ACS72981xLR datasheet. The ACS720 is used validate the test methods presented, but these same methods and principles would also apply to the ACS724, ACS71240, and ACS72981. ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/P/O/POLOLU-5252-1.jpg)