ACS37041KLHBLT-030B3 Current Sensor Micro Carrier -30A to +30A, 3.3V

Overview

ACS37041 Current Sensor Micro Carrier (top) and Compact Carrier (bottom) basic dimensions with US quarter for size reference.

We are offering these breakout boards with support from Allegro Microsystems as an easy way to use or evaluate their ACS37041 Hall effect-based, electrically isolated current sensors; we therefore recommend careful reading of the ACS37041 datasheet before using this product. The following list details some of the sensor’s key features:

• Hall effect-based sensor with electrically isolated current path allows the sensor to be inserted anywhere along the current path and to be used in applications that require galvanic isolation.
• Low primary current path resistance of 1.6 mΩ in the sensor IC, so very little power is lost in the module.
• Differential Hall sensing rejects common-mode fields, so the orientation of the sensor relative to uniform external magnetic fields (e.g. the Earth’s magnetic field) has less effect on the measurement.
• High-bandwidth 150 kHz analog output voltage proportional to AC or DC currents.
• Less than 5 µs response time.
• Output is not ratiometric (i.e. the zero point and sensitivity are independent of the actual supply voltage), which provides immunity from noisy supplies.
• Integrated temperature compensation circuitry allows improved accuracy over the full operating temperature range.
• Automotive-grade operating temperature range of -40°C to 125°C.
• Carrier boards, available in micro (0.3″×0.4″) and our standard compact (0.7″×0.8″) sizes, offer a variety of ways to insert it into the current path along with 0.1″-pitch (breadboard-compatible) power, ground, and output pins.
• 3.3V and 5V versions available.

The connection points and the direction interpreted as positive current flow are labeled on the bottom silkscreen.

The following table lists the available ACS37041 carrier options:

	Pololu Item #	Part Suffix	Supply Voltage	Current Range	Sensitivity (mV/A)	Zero Point	Size	PCB Details	Price
Micro Carriers
	#5440 (coming June 2025)	010B3	3.0 V to 3.6 V	±10 A	132	1.65 V	0.3″×0.4″	2 layers, 1-oz copper	$3.19
	#5441	030B3		±30 A	44
	#5442	010B5	4.5 V to 5.5 V	±10 A	200	2.5 V
	#5443	030B5		±30 A	66.7
Compact Carriers
	#5444 (coming June 2025)	010B3	3.0 V to 3.6 V	±10 A	132	1.65 V	0.7″×0.8″	2 layers, 2-oz copper	$3.49
	#5445	030B3		±30 A	44
	#5446	010B5	4.5 V to 5.5 V	±10 A	200	2.5 V
	#5447	030B5		±30 A	66.7

Alternatives available with variations in these parameter(s): current range size Select variant…

Details for item #5441

ACS37041KLHBLT-030B3 Current Sensor Micro Carrier -30A to +30A, 3.3V.

ACS37041 Current Sensor Micro Carrier.

This micro carrier features the ACS37041KLHBLT-030B3, which is intended for nominal 3.3 V operation and is designed for bidirectional input current from -30 A to +30 A. This version can be visually distinguished from the other versions by the “3B3” printed on the bottom side, as shown in the left picture above.

Part Suffix	Range	Supply Voltage	Sensitivity	Zero Point	Size	PCB
030B3	±30 A (bidirectional)	3.0 V to 3.6 V	44 mV/A	1.65 V	0.3″×0.4″	2 layers, 1-oz copper

A larger carrier with our standard compact form factor 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

This sensor has five required connections: the input current (IP+ and IP-), logic power (VDD and GND), and the sensor output (VOUT).

The sensor requires a supply voltage of 3.0 V to 3.6 V to be connected across the VDD and GND pads, which are labeled on the bottom silkscreen. The sensor outputs an analog voltage on VOUT that is centered at 1.65 V and changes by 132 mV per amp of input current, with positive current increasing the output voltage and negative current decreasing the output voltage:

``V_"OUT" = 1.65 text(V) + 0.044 text(V)/text(A) * I_"P"``

``I_"P" = (V_"OUT" – 1.65 text(V)) / (0.044 text(V)/text(A)) = (V_"OUT" – 1.65 text(V)) * 22.7 text(A)/text(V)``

The output is not ratiometric, so the zero point and sensitivity are independent of the actual supply voltage.

Making connections to the board

The VOUT, VDD, and GND pins work with 0.1″-pitch header pins and are compatible with standard solderless breadboards

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 0.045″×0.095″ slots. The slots can also accommodate 3.5mm-pitch and 5mm-pitch terminal blocks as shown below:

The current path slots can also accommodate a 1×2 0.2″-pitch header or a 1×3 0.1″-pitch male header with the middle pin removed, and in this configuration, the board can span the gap in the middle of a breadboard if male headers are also soldered to the VOUT, VDD, and GND pins. Alternatively, a pair of 1×2 0.1″ headers can be added between each slot and the singular hole below it along the longer edges, but please note that this configuration does not allow the board to span the gap in a breadboard.

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

ACS37041/2 Current Sensor Carrier schematic diagram.

The dimension diagram is available as a downloadable PDF (416k pdf).

Real-world power dissipation considerations

Thermal image of a high-current test of a Pololu current sensor carrier (not necessarily this product).

In our tests, we found that the micro carrier board (cs08a) could conduct about 25 A continuously, and compact carrier board (cs08b) could conduct about 30 A continuously, without reaching the thermal limit for the IC. Our 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 20 A, we 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.

Comparison of the Pololu current sensor carriers

We have a variety of current sensors available with different ranges, sensitivities, and features. The table below summarizes our selection of active and preferred options:

You can also use the following selection box to see all these options sorted by current range:

Alternatives available with variations in these parameter(s): current range Select variant…