# ACS72981LLRATR-100B5 Current Sensor Compact Carrier -100A to +100A, 5V **Type:** Product page · **SKU:** POLOLU-5254 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia) **Page:** https://core-electronics.com.au/acs72981llratr-100b5-current-sensor-compact-carrier-100a-to-100a-5v.html ([markdown](https://core-electronics.com.au/acs72981llratr-100b5-current-sensor-compact-carrier-100a-to-100a-5v.html.md)) This is the compact version of a simple carrier for Allegro’s ACS72981LLRATR-100B5 Hall effect-based, electrically isolated current sensor, which offers a... ## 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 The ACS72981 Current Sensor Compact Carrier is designed for nominal 5 V operation and is intended for bidirectional input current from -100 A to +100 A. This version can be visually distinguished from other versions by the “5V B10” printed on the bottom side. This compact carrier features the ACS72981LLRATR-100B5, which is designed for bidirectional input current from -100 A to +100 A. The sensor outputs a ratiometric analog voltage on VIOUT that is centered at VCC/2 and changes by 20 mV × (VCC/5 V) per amp of input current, with positive current increasing the output voltage and negative current decreasing the output voltage. 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 4.5 V to 5.5 V to be connected across the VCC and GND pads, which are labeled on the bottom silkscreen. 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). You can insert the board into your current path in various 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. 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 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. **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** The dimension diagram is available as a **downloadable PDF** (400k pdf). **Real-world power dissipation considerations** 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 recommends 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. **Comparison of the Pololu current sensor carriers** Pololu has a variety of current sensors available with different ranges, sensitivities, and features. The table below summarizes Pololu's selection of active and preferred options: **Dimensions** | Size: | 0.7" × 0.8" | |---|---| | Weight: | 1.4 g | **General specifications** | Typical operating voltage: | 5 V | |---|---| | Current sense: | 20 mV/A[1](https://core-electronics.com.au/#note1) | | Minimum logic voltage: | 4.5 V | | Maximum logic voltage: | 5.5 V | | Supply current: | 14 mA[2](https://core-electronics.com.au/#note2) | | Current range: | -100A to +100A (bidirectional 100A), 5V | | Current sensor: | Allegro ACS72981LLRATR-100B5 | **Identifying markings** | PCB dev codes: | cs04a | |---|---| | Other PCB markings: | 0J14752 | | Other PCB markings: | 5V B10 | **Notes:** 1 At VCC = 5 V. 2 Typical.**File downloads** - **Dimension diagrams of the ACS72981xLR Current Sensor Carriers (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 to validate the test methods presented, but these same methods and principles would also apply to the ACS724, ACS71240, and ACS72981. - **[Allegro product page for the ACS72981 Hall-based Current Sensor](https://www.allegromicro.com/en/products/sense/current-sensor-ics/fifty-to-two-hundred-amp-integrated-conductor-sensor-ics/acs72981)** Allegro product page for the ACS72981, where you can find additional application notes and other resources. ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/P/O/POLOLU-5254-1.jpg)