ACS712 Hall-effect current sensor pinout

The ACS712 reports the current in its integrated conductor as an analog voltage centered on half the sensor supply.

LC SOIC-8

8 contacts Current package

Allegro MicroSystems · Allegro LC, 8-lead narrow small-outline package.

±20 A optimized range, 100 mV/A typical at 5 V and 25 °C.

Top view. Locate the package index before counting counterclockwise from pin 1.

Primary conductor · Inputs

First lead of the internally common positive current terminal. Join to pin 2.

Allegro ACS712-DS Rev. 22, pinout diagram

Pin	Signal	Direction	Function
1	IP+ Primary conductor	Primary conductor	First lead of the internally common positive current terminal. Join to pin 2.
2	IP+ Primary conductor	Primary conductor	Second lead of the positive current terminal. Join to pin 1.
3	IP− Primary conductor	Primary conductor	First lead of the internally common negative current terminal. Join to pin 4.
4	IP− Primary conductor	Primary conductor	Second lead of the negative current terminal. Join to pin 3.
5	GND Return	Return	Signal-side reference for the supply, output and filter capacitor.
6	FILTER Filter node	Filter node	A capacitor here to GND limits the output bandwidth.
7	VIOUT Output	Output	Ratiometric voltage output. Current from IP+ toward IP− raises this voltage.
8	VCC Supply	Supply	Nominal 5 V supply. Bypass near this lead to GND.

Use both leads of each primary terminal. The sample current flows through the integrated copper conductor in series with the load.

Calculate current from the voltage difference relative to the measured zero-current output. The slope depends on the part suffix and supply voltage.

Parameter	Limit	Conditions and source
Optimized range±20 A	±20 A	See the thermal data for PCB and ambient conditions. Allegro ACS712-DS Rev. 22
Sensitivity100 mV/A typical	100 mV/A typical	At 5 V and 25 °C. Allegro ACS712-DS Rev. 22
Sensor supply4.5–5.5 V	4.5–5.5 V	5 V nominal. Allegro ACS712-DS Rev. 22, common operating characteristics
Zero-current outputVCC ÷ 2 nominal	VCC ÷ 2 nominal	Offset varies with temperature. Record the actual zero before measuring current. Allegro ACS712-DS Rev. 22
Conductor resistance1.2 mΩ typical	1.2 mΩ typical	Primary conductor. PCB copper and heat sinking determine practical current capability. Allegro ACS712-DS Rev. 22

The LC-package sensing ranges share one terminal map. Match the exact suffix before converting voltage to amperes.

ACS712ELCTR-05B-T: ±5 A optimized range, 185 mV/A typical at 5 V and 25 °C.
ACS712ELCTR-20A-T: ±20 A optimized range, 100 mV/A typical at 5 V and 25 °C.
ACS712ELCTR-30A-T: ±30 A optimized range, 66 mV/A typical at 5 V and 25 °C.
ACS712ELCTR-20A-S: ±20 A optimized range, 100 mV/A typical at 5 V and 25 °C.
ACS712ELCTR-30A-S: ±30 A optimized range, 66 mV/A typical at 5 V and 25 °C.

Allegro ACS712-DS Rev. 22· Selection guide, package drawing, terminal functions and sensitivity tables.
Source register· Document revisions, applicable order codes, consulted sections and available file checksums.