ACS715

ACS715 ALLEGRO | Alldatasheet

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Approximate Scale 1:1 that varies linearly with the unidirectional DC primary sensed current, I P , within the range specified. CF is recommended for noise management, with values that depend on the application. ACS715

Description

The Allegro ® ACS715 provides economical and precise solutions for DC current sensing in automotive systems. The device package allows for easy implementation by the customer. Typical applications include motor control, load detection and management, switched-mode power supplies, and overcurrent fault protection. The device consists of a precise, low-offset, linear Hall sensor circuit with a copper conduction path located near the surface of the die. Applied current flowing through this copper conduction path generates a magnetic field which is sensed by the integrated Hall IC and converted into a proportional voltage. Device accuracy is optimized through the close proximity of the magnetic signal to the Hall transducer. A precise, proportional voltage is provided by the low-offset, chopper-stabilized BiCMOS Hall IC, which is programmed for accuracy after packaging. The output of the device has a positive slope (>V IOUT(Q)) when an increasing current flows through the primary copper conduction path (from pins 1 and 2, to pins 3 and 4), which is the path used for current sensing. The internal resistance of this conductive path is 1.2 mΩ typical, providing low power loss. The thickness of the copper conductor allows survival ACS715-DS Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current Conductor Continued on the next page… Package: 8 Lead SOIC (suffix LC) Typical Application IP+ IP+ IP– IP– 5GND ACS715 VIOUT 6FILTER VCC IP +5 V VOUT CF CBYP 0.1 μF Features and Benefits ▪ Low-noise analog signal path ▪ Device bandwidth is set via the FILTER pin ▪ 5 μs output rise time in response to step input current ▪ 80 kHz bandwidth ▪ Total output error 1.5% typical at T A = 25°C ▪ Small footprint, low-profile SOIC8 package ▪ 1.2 m Ω internal conductor resistance ▪ 2.1 kV RMS minimum isolation voltage from pins 1-4 to pins 5-8 ▪ 5.0 V , single supply operation ▪ 133 to 185 mV/A output sensitivity ▪ Output voltage proportional to DC currents ▪ Factory-trimmed for accuracy ▪ Extremely stable output offset voltage ▪ Nearly zero magnetic hysteresis ▪ Ratiometric output from supply voltage ▪ Operating temperature range, –40°C to 150°C

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 2Allegro MicroSystems, Inc.

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com of the device at up to 5× overcurrent conditions. The terminals of the conductive path are electrically isolated from the sensor leads (pins 5 through 8). This allows the ACS715 current sensor to be used in applications requiring electrical isolation without the use of opto-isolators or other costly isolation techniques. The ACS715 is provided in a small, surface mount SOIC8 package. The leadframe is plated with 100% matte tin, which is compatible with standard lead (Pb) free printed circuit board assembly processes. Internally, the device is Pb-free, except for flip-chip high-temperature Pb-based solder balls, currently exempt from RoHS. The device is fully calibrated prior to shipment from the factory. Description (continued) TÜV America Certificate Number: U8V 06 05 54214 010 Parameter Specification Fire and Electric Shock CAN/CSA-C22.2 No. 60950-1-03 UL 60950-1:2003 EN 60950-1:2001 Selection Guide Part Number Optimized Range, IP (A) Sensitivity, Sens (Typ) (mV/A) TA (°C) Packing* ACS715ELCTR-20A-T 0 to 20 185 –40 to 85 Tape and reel, 3000 pieces/reel ACS715ELCTR-30A-T 0 to 30 133 ACS715LLCTR-20A-T 0 to 20 185 –40 to 150 ACS715LLCTR-30A-T 0 to 30 133 *Contact Allegro for additional packing options. Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Supply Voltage V CC 8V Reverse Supply Voltage V RCC –0.1 V Output Voltage V IOUT 8V Reverse Output Voltage V RIOUT –0.1 V Reinforced Isolation Voltage V ISO Pins 1-4 and 5-8; 60 Hz, 1 minute, TA=25°C 2100 V Rated Input Voltage V working Voltage applied to leadframe (Ip+ pins) 184 V AC Max Output Current Source I OUT(Source) 3m A Output Current Sink I OUT(Sink) 10 mA Overcurrent Transient Tolerance I P 1 pulse, 100 ms 100 A Nominal Operating Ambient Temperature T A Range E –40 to 85 ºC Range L –40 to 150 ºC Maximum Junction Temperature T J(max) 165 ºC Storage Temperature T stg –65 to 170 ºC

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 3Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com VCC (Pin 8) (Pin 7) VIOUT GND (Pin 5) FILTER (Pin 6) Dynamic Offset Cancellation IP+ (Pin 1) IP+ (Pin 2) IP– (Pin 3) IP– (Pin 4) Sense Trim Signal Recovery Sense Temperature Coefficient Trim

0 Ampere

+5 V IP+ IP+ IP– IP– VCC VIOUT FILTER GND Terminal List Table Number Name Description 1 and 2 IP+ Input terminals for current being sensed; fused internally 3 and 4 IP– Output terminals for current being sensed; fused internally

5 GND Signal ground terminal

6 FILTER Terminal for external capacitor that sets bandwidth

7 VIOUT Analog output signal

8 VCC Device power supply terminal

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 4Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com COMMON THERMAL CHARACTERISTICS1 Min. Typ. Max. Units Operating Internal Leadframe Temperature T A E range –40 – 85 °C L range –40 – 150 °C Value Units Junction-to-Lead Thermal Resistance2 RθJL Mounted on the Allegro ASEK 715 evaluation board 5 °C/W Junction-to-Ambient Thermal Resistance2,3 RθJA Mounted on the Allegro 85-0322 evaluation board, includes the power consumed by the board 23 °C/W 1Additional thermal information is available on the Allegro website. 2The Allegro evaluation board has 1500 mm2 of 2 oz. copper on each side, connected to pins 1 and 2, and to pins 3 and 4, with thermal vias connect- ing the layers. Performance values include the power consumed by the PCB. Further details on the board are available from the Frequently Asked Questions document on our website. Further information about board design and thermal performance also can be found in the Applications Informa- tion section of this datasheet. 3RθJA values shown in this table are typical values, measured on the Allegro evaluation board. The actual thermal performance depends on the actual application board design, the airflow in the application, and thermal interactions between the sensor and surrounding components through the PCB and the ambient air. To improve thermal performance, see our applications material on the Allegro website. COMMON OPERATING CHARACTERISTICS1 over full range of TA, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Units

ELECTRICAL CHARACTERISTICS

Supply Voltage V CC 4.5 5.0 5.5 V Supply Current I CC VCC = 5.0 V, output open – 10 13 mA Output Capacitance Load C LOAD VIOUT to GND – – 10 nF Output Resistive Load R LOAD VIOUT to GND 4.7 – – k Ω Primary Conductor Resistance R PRIMARY TA = 25°C – 1.2 – m Ω Rise Time t r IP = IP(max), TA = 25°C, COUT = 10 nF – 5 – μs Frequency Bandwidth f –3 dB, T A = 25°C; IP is 10 A peak-to-peak – 80 – kHz Nonlinearity E LIN Over full range of IP , IP applied for 5 ms – ±1.5 – % Symmetry E SYM Over full range of IP , IP applied for 5 ms 98 100 102 % Zero Current Output Voltage V IOUT(Q) Unidirectional; IP = 0 A, TA = 25°C – VCC × 0.1 –V Power-On Time t PO Output reaches 90% of steady-state level, no capacitor on FILTER pin; TJ = 25; 20 A present on leadframe –3 5– μs Magnetic Coupling2 – 12 – G/A Internal Filter Resistance3 RF(INT) 1.7 k Ω 1Device may be operated at higher primary current levels, IP, and ambient, TA , and internal leadframe temperatures, TA , provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 21G = 0.1 mT. 3RF(INT) forms an RC circuit via the FILTER pin.

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 5Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com x20A PERFORMANCE CHARACTERISTICS over Range E: TA = –40°C to 85°C1, CF = 1 nF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Units Optimized Accuracy Range I P 0 – 20 A Sensitivity Sens Over full range of I P , IP applied for 5ms; TA = 25°C 178 185 190 mV/A Noise V NOISE(PP) Peak-to-peak, TA = 25°C, 2 kHz external filter, 185 mV/A pro- grammed Sensitivity, CF = 47 nF, COUT = 10 nF, 2 kHz bandwidth –2 1–m V Zero Current Output Slope ∆IOUT(Q) TA = –40°C to 25°C – 0.08 – mV/°C TA = 25°C to 150°C – 0.16 – mV/°C Sensitivity Slope ∆Sens TA = –40°C to 25°C – 0.035 – mV/A/°C TA = 25°C to 150°C – 0.019 – mV/A/°C Electrical Offset Voltage V OE IP = 0 A –40 – 40 mV Total Output Error2 ETOT IP = 20 A , IP applied for 5 ms; TA = 25°C – ±1.5 – % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TA, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 2Percentage of IP, with IP = 20 A. Output filtered. x20A PERFORMANCE CHARACTERISTICS over Range L: TA = –40°C to 150°C1, CF = 1 nF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Units Optimized Accuracy Range I P 0 – 20 A Sensitivity Sens Over full range of IP , IP applied for 5ms; TA = 25°C – 185 – mV/A Over full range of IP, TA = –40°C to 150°C 161 – 194 mV/A Noise V NOISE(PP) Peak-to-peak, TA = 25°C, 2 kHz external filter, 185 mV/A pro- grammed Sensitivity, CF = 47 nF, COUT = 10 nF, 2 kHz bandwidth –2 1–m V Zero Current Output Slope ∆IOUT(Q) TA = –40°C to 25°C – 0.08 – mV/°C TA = 25°C to 150°C – 0.16 – mV/°C Sensitivity Slope ∆Sens TA = –40°C to 25°C – 0.035 – mV/A/°C TA = 25°C to 150°C – 0.019 – mV/A/°C Electrical Offset Voltage V OE IP = 0 A –60 – 60 mV Total Output Error2 ETOT IP = 20 A , IP applied for 5 ms; TA = 25°C – ±1.5 – % IP = 20 A , IP applied for 5 ms; TA = –40° to 150°C –6 – 6 % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TA, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 2Percentage of IP, with IP = 20 A. Output filtered.

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 6Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com x30A PERFORMANCE CHARACTERISTICS over Range E: TA = –40°C to 85°C1, CF = 1 nF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Units Optimized Accuracy Range I P 0 – 30 A Sensitivity Sens Over full range of I P , IP applied for 5ms; TA = 25°C 129 133 137 mV/A Noise V NOISE(PP) Peak-to-peak, TA = 25°C, 2 kHz external filter, 133 mV/A pro- grammed Sensitivity, CF = 47 nF, COUT = 10 nF, 2 kHz bandwidth –1 5–m V Zero Current Output Slope ∆IOUT(Q) TA = –40°C to 25°C – 0.06 – mV/°C TA = 25°C to 150°C – 0.1 – mV/°C Sensitivity Slope ∆Sens TA = –40°C to 25°C – 0.007 – mV/A/°C TA = 25°C to 150°C – –0.025 – mV/A/°C Electrical Offset Voltage V OE IP = 0 A –30 – 30 mV Total Output Error2 ETOT IP = 30 A , IP applied for 5 ms; TA = 25°C – ±1.5 – % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TA, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 2Percentage of IP, with IP = 30 A. Output filtered. x30A PERFORMANCE CHARACTERISTICS over Range L: TA = –40°C to 150°C1, CF = 1 nF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Units Optimized Accuracy Range I P 0 – 30 A Sensitivity Sens Over full range of IP , IP applied for 5ms; TA = 25°C – 133 – mV/A Over full range of IP, TA = –40°C to 150°C 125 – 137 mV/A Noise V NOISE(PP) Peak-to-peak, TA = 25°C, 2 kHz external filter, 133 mV/A pro- grammed Sensitivity, CF = 47 nF, COUT = 10 nF, 2 kHz bandwidth –1 5–m V Zero Current Output Slope ∆IOUT(Q) TA = –40°C to 25°C – 0.06 – mV/°C TA = 25°C to 150°C – 0.1 – mV/°C Sensitivity Slope ∆Sens TA = –40°C to 25°C – 0.007 – mV/A/°C TA = 25°C to 150°C – –0.025 – mV/A/°C Electrical Offset Voltage V OE IP = 0 A –40 – 40 mV Total Output Error2 ETOT IP = 30 A , IP applied for 5 ms; TA = 25°C – ±1.5 – % IP = 30 A , IP applied for 5 ms; TA = –40° to 150°C –5 – 5 % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TA, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 2Percentage of IP, with IP = 30 A. Output filtered.

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 7Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com –40 150 TA (°C)–40 –20 125 TA (°C) IP = 0 A IP = 0 A VCC = 5 V VCC = 5 V VCC = 5 V VCC = 5 V; IP = 0 A, After excursion to 20 A Mean Supply Current versus Ambient Temperature Sensitivity versus Sensed Current 200.00 198.00 196.00 194.00 192.00 190.00 188.00 186.00 184.00 182.00 180.00 178.00 176.00 174.00 Sens (mV/A) Ip (A) TA (°C) TA (°C) Mean ICC (mA) 10.5 10.4 10.3 10.2 10.1 10.0 9.9 9.8 9.7 9.6 -50 -25 0 25 50 75 125 100 150 Supply Current versus Supply Voltage 11.2 11.0 10.8 10.6 10.4 10.2 10.0 9.8 9.6 VCC (V) ICC (mA) Nonlinearity versus Ambient Temperature 0.35 0.30 0.25 0.20 0.15 0.10 0.05 –50 0 –25 25 50 12575 100 150 ELIN (%) TA (°C) Mean Total Output Error versus Ambient Temperature –50 0 –25 25 50 12575 100 150 0 1051 5 20 3525 30 ETOT (%) IP (A) Output Voltage versus Sensed Current 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 VIOUT (V) 188 187 186 185 184 183 182 Sens (mV/A) TA (°C) Sensitivity versus Ambient Temperature –50 0 –25 25 50 12575 100 150 TA (°C) IOM (mA) –0.5 –1.0 –1.5 –2.0 –2.5 –3.0 –3.5 –4.0 –4.5 –5.0 -50 -25 0 25 50 75 125 100 150 Magnetic Offset versus Ambient Temperature

0 A Output Voltage versus Ambient Temperature

TA (°C) VIOUT(Q) (mV) 5250 5200 5150 5100 5050 5000 4950 4900 -50 -25 0 25 50 75 125 100 150

0 A Output Voltage Current versus Ambient Temperature

TA (°C) IOUT(Q) (A) –19.75 –19.80 –19.85 –19.90 –19.95 –20.00 –20.05 –20.10 -50 -25 0 25 50 75 125 100 150 0 5 10 15 20 25 Characteristic Performance IP = 20 A, unless otherwise specified

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 8Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com Characteristic Performance IP = 30 A, unless otherwise specified –40 150 TA (°C)–40 –20 125 TA (°C) IP = 0 A IP = 0 A VCC = 5 V VCC = 5 V VCC = 5 V VCC = 5 V; IP = 0 A, After excursion to 20 A Mean Supply Current versus Ambient Temperature Sensitivity versus Sensed Current 140 139 138 137 136 135 134 133 132 131 130 129 128 127 126 125 Sens (mV/A) Ip (A) TA (°C) TA (°C) Mean ICC (mA) 10.1 10.0 9.9 90.8 9.7 9.6 9.5 9.4 -50 -25 0 25 50 75 125 100 150 Supply Current versus Supply Voltage 10.8 10.6 10.4 10.2 10.0 9.8 9.6 9.4 VCC (V) ICC (mA) Nonlinearity versus Ambient Temperature 0.35 0.30 0.25 0.20 0.15 0.10 0.05 –50 0–25 25 50 12575 100 150 ELIN (%) TA (°C) Mean Total Output Error versus Ambient Temperature –50 0 –25 25 50 12575 100 150 01 0 51 5 2 0 3525 30 ETOT (%) IP (A) Output Voltage versus Sensed Current 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 VIOUT (V) 133.5 133.0 132.5 132.0 131.5 131.0 130.5 130.0 129.5 Sens (mV/A) TA (°C) Sensitivity versus Ambient Temperature –50 0 –25 25 50 12575 100 150 TA (°C) IOM (mA) –0.5 –1.0 –1.5 –2.0 –2.5 –3.0 –3.5 –4.0 –4.5 –5.0 -50 -25 0 25 50 75 125 100 150 Magnetic Offset versus Ambient Temperature TA (°C) VIOUT(Q) (mV) 5140 5120 5100 5080 5060 5040 5020 5000 4980 4960 4940 -50 -25 0 25 50 75 125 100 150 TA (°C) IOUT(Q) (A) –10 –15 –20 –25 –30 –35 -50 -25 0 25 50 75 125 100 150 VCC = 5 V

0 A Output Voltage versus Ambient Temperature 0 A Output Voltage Current versus Ambient Temperature

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 9Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com Sensitivity (Sens). The change in sensor output in response to a 1 A change through the primary conductor. The sensitivity is the product of the magnetic circuit sensitivity (G / A) and the linear IC amplifier gain (mV/G). The linear IC amplifier gain is pro- grammed at the factory to optimize the sensitivity (mV/A) for the full-scale current of the device. Noise (V NOISE). The product of the linear IC amplifier gain (mV/G) and the noise floor for the Allegro Hall effect linear IC (≈1 G). The noise floor is derived from the thermal and shot noise observed in Hall elements. Dividing the noise (mV) by the sensitivity (mV/A) provides the smallest current that the device is able to resolve. Linearity (E LIN). The degree to which the voltage output from the sensor varies in direct proportion to the primary current through its full-scale amplitude. Nonlinearity in the output can be attributed to the saturation of the flux concentrator approaching the full-scale current. The following equation is used to derive the linearity: where V IOUT_full-scale amperes = the output voltage (V) when the sensed current approximates full-scale ±IP . Quiescent output voltage (VIOUT(Q)). The output of the sensor when the primary current is zero. For a unipolar supply voltage, it nominally remains at VCC ⁄ 2. Thus, VCC = 5 V translates into VIOUT(Q) = 2.5 V . Variation in VIOUT(Q) can be attributed to the resolution of the Allegro linear IC quiescent voltage trim and thermal drift. Electrical offset voltage (V OE). The deviation of the device out- put from its ideal quiescent value of VCC / 2 due to nonmagnetic causes. To convert this voltage to amperes, divide by the device sensitivity, Sens. Accuracy (E TOT). The accuracy represents the maximum devia- tion of the actual output from its ideal value. This is also known as the total ouput error. The accuracy is illustrated graphically in the output voltage versus current chart at right. Accuracy is divided into four areas:

• 0 A at 25°C. Accuracy of sensing zero current flow at 25°C, without the effects of temperature.
• 0 A over Δ temperature. Accuracy of sensing zero current flow including temperature effects.
• Full-scale current at 25°C. Accuracy of sensing the full-scale current at 25°C, without the effects of temperature.
• Full-scale current over Δ temperature. Accuracy of sensing full- scale current flow including temperature effects. Ratiometry. The ratiometric feature means that its 0 A output, V IOUT(Q), (nominally equal to VCC/2) and sensitivity, Sens, are proportional to its supply voltage, VCC . The following formula is used to derive the ratiometric change in 0 A output voltage, ΔV IOUT(Q)RAT (%). The ratiometric change in sensitivity, ΔSensRAT (%), is defined as: Definitions of Accuracy Characteristics 100 1– [{ [ { VIOUT_full-scale amperes – VIOUT(Q)Δ gain × % sat ( ) 2 (VIOUT_half-scale amperes – VIOUT(Q) ) 100 VIOUT(Q)VCC / VIOUT(Q)5V VCC / 5 V 100 SensVCC / Sens5V VCC / 5 V‰ /c144 Output Voltage versus Sensed Current Accuracy at 0 A and at Full-Scale Current Increasing VIOUT(V) +IP (A) Accuracy Accuracy 25°C Only Accuracy 25°C Only Accuracy 0 A vrOe $Temp erature Average VIOUT –IP (A) vrOe $Temp erature Decreasing VIOUT(V) 30 A Full Scale

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 10Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com Power on Time versus External Filter Capacitance 100 120 140 160 180 200 01 0 2 0 3 0 4 0 5 0 CF (nF) CF (nF) tPO (μs) IP=5 A IP=0 A Noise versus External Filter Capacitance 1000 100 10000 0.01 0.1 1 10 100 1000 Noise(p-p) (mA) Noise vs. Filter Cap 400 350 300 250 200 150 100 05 0 25 75 100 125 150 tr(μs) CF (nF) Rise Time versus External Filter CapacitanceRise Time versus External Filter Capacitance 200 400 600 800 1000 1200 0 100 200 300 400 500 tr(μs) CF (nF) Expanded in chart at right CF (nF) t r (μs) 0 6.6 1 7.7 4.7 17.4 10 32.1 22 68.2 47 88.2 100 291.3 220 623.0 470 1120.0 Definitions of Dynamic Response Characteristics Primary Current Transducer Output I (%) Rise Time, tr t Rise time (tr). The time interval between a) when the sensor reaches 10% of its full scale value, and b) when it reaches 90% of its full scale value. The rise time to a step response is used to derive the bandwidth of the current sensor, in which ƒ(–3 dB) = 0.35 / t r. Both tr and tRESPONSE are detrimentally affected by eddy current losses observed in the conductive IC ground plane. Power-On Time (tPO). When the supply is ramped to its operat- ing voltage, the device requires a finite time to power its internal components before responding to an input magnetic field. Power-On Time, t PO , is defined as the time it takes for the output voltage to settle within ±10% of its steady state value under an applied magnetic field, after the power supply has reached its minimum specified operating voltage, V CC(min), as shown in the chart at right.

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 11Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com Chopper Stabilization is an innovative circuit technique that is used to minimize the offset voltage of a Hall element and an asso- ciated on-chip amplifier. Allegro patented a Chopper Stabiliza- tion technique that nearly eliminates Hall IC output drift induced by temperature or package stress effects. This offset reduction technique is based on a signal modulation-demodulation process. Modulation is used to separate the undesired dc offset signal from the magnetically induced signal in the frequency domain. Then, using a low-pass filter, the modulated dc offset is suppressed while the magnetically induced signal passes through the filter. As a result of this chopper stabilization approach, the output voltage from the Hall IC is desensitized to the effects of tempera- ture and mechanical stress. This technique produces devices that have an extremely stable Electrical Offset V oltage, are immune to thermal stress, and have precise recoverability after temperature cycling. This technique is made possible through the use of a BiCMOS process that allows the use of low-offset and low-noise amplifiers in combination with high-density logic integration and sample and hold circuits. IP+ IP+ IP– IP– IP +5 V LMV7235 VIOUT VOUT GND FILTER VCC ACS715 1N914 100 kΩ 33 kΩ RPU 100 kΩ Fault CBYP 0.1 μF CF Application 2. 10 A Overcurrent Fault Latch. Fault threshold set by R1 and R2. This circuit latches an overcurrent fault and holds it until the 5 V rail is powered down. Application 4. Control circuit for MOSFET ORing. Amp Regulator Clock/Logic Hall Element Sample and Hold Low-Pass Filter Chopper Stabilization TechniqueChopper Stabilization Technique Concept of Chopper Stabilization Technique IP+ IP+ IP– IP– +5 VVS1 LMC6772 10 kΩ FDS6675a 2N7002 VIOUT VOUT VREF GND

3 FILTER

100 kΩ CBYP 0.1 μF CF IP1 IP+ IP+ IP– IP– +5 VVS2 LMC6772 10 kΩ FDS6675a 2N7002 VIOUT VOUT VREF GND 100 kΩ CBYP 0.1 μF CF IP2 Typical Applications –IP+ IP+ IP– IP– +5 V LM321 VIOUT VOUT GND 1 4 FILTER VCC ACS715 100 kΩ 100 kΩ 3.3 kΩ CBYP 0.1 μF CF 0.01 μF 1000 pF RF 1 kΩIP Application 3. This configuration increases gain to 610 mV/A (tested using the ACS712ELC-05A).

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 12Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com Improving Sensing System Accuracy Using the FILTER Pin In low-frequency sensing applications, it is often advantageous to add a simple RC filter to the output of the sensor. Such a low- pass filter improves the signal-to-noise ratio, and therefore the resolution, of the sensor output signal. However, the addition of an RC filter to the output of a sensor IC can result in undesirable sensor output attenuation — even for dc signals. Signal attenuation, ∆V ATT , is a result of the resistive divider effect between the resistance of the external filter, RF (see Appli- cation 5), and the input impedance and resistance of the customer interface circuit, R INTFC. The transfer function of this resistive divider is given by: Even if RF and RINTFC are designed to match, the two individual resistance values will most likely drift by different amounts over temperature. Therefore, signal attenuation will vary as a function of temperature. Note that, in many cases, the input impedance, RINTFC , of a typical analog-to-digital converter (ADC) can be as low as 10 kΩ. The ACS715 contains an internal resistor, a FILTER pin connec- tion to the printed circuit board, and an internal buffer ampli- fier. With this circuit architecture, users can implement a simple RC filter via the addition of a capacitor, C F (see Application 6) from the FILTER pin to ground. The buffer amplifier inside of the ACS715 (located after the internal resistor and FILTER pin connection) eliminates the attenuation caused by the resistive divider effect described in the equation for ∆V ATT. Therefore, the ACS715 device is ideal for use in high-accuracy applications that cannot afford the signal attenuation associated with the use of an external RC low-pass filter. =∆VATT RINTFC RF + RINTFC VIOUT ⎟⎠ ⎛ . Application 5. When a low pass filter is construct- ed externally to a standard Hall effect device, a resistive divider may exist between the filter resistor, R F, and the resistance of the custom- er interface circuit, RINTFC. This resistive divider will cause excessive attenuation, as given by the transfer function for ∆V ATT. Application Interface Circuit Resistive Divider RINTFC Low Pass Filter RF CF Amp Out VCC +5 V Pin 8 Pin 7 VIOUT Pin 6 N.C. Input GND Pin 5 Filter Dynamic Offset Cancellation IP+ IP+ 0.1 MF Pin 1 Pin 2 IP– IP– Pin 3 Pin 4 Gain Temperature Coefficient Offset Voltage Regulator Trim Control To all subcircuits Input VCC Pin 8 Pin 7 VIOUT GND Pin 5 FILTER Pin 6 Dynamic Offset Cancellation IP+ Pin 1 IP+ Pin 2 IP– Pin 3 IP– Pin 4 Sense Trim Signal Recovery Sense Temperature Coefficient Trim +5 V Application Interface Circuit Buffer Amplifier and Resistor RINTFC CF Allegro ACS715 Allegro ACS706 Application 6. Using the FILTER pin provided on the ACS715 eliminates the attenuation effects of the resis- tor divider between R F and RINTFC, shown in Application 5.

Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current ConductorACS715 13Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com

1.75 MAX

0.18 4º 4.90 3.90 6.00 0.84 0.21 0.41 0.25 SEATING PLANE 1.27 C0.10 8X C GAUGE PLANE SEATING PLANE A A Terminal #1 mark area All dimensions nominal, not for tooling use (reference JEDEC MS-012 AA) Dimensions in millimeters Package LC, 8-pin SOIC ACS715T RLCPPP YYWWA ACS Allegro Current Sensor

715 Device family number

T Indicator of 100% matte tin leadframe plating R Operating ambient temperature range code PPP Primary sensed current YY Date code: Calendar year (last two digits) WW Date code: Calendar week A Date code: Shift code ACS715T RLCPPP L...L YYWW ACS Allegro Current Sensor T Indicator of 100% matte tin leadframe plating R Operating ambient temperature range code PPP Primary sensed current L...L Lot code YY Date code: Calendar year (last two digits) WW Date code: Calendar week Package Branding Two alternative patterns are used Text 1 Text 2 Text 3 1 For the latest version of this document, go to our website at: www.allegromicro.com Copyright ©2006, 2007, Allegro MicroSystems, Inc. The products described herein are manufactured under one or more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283; 5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719; 5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents pending. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such de par tures from the detail spec i fi ca tions as may be required to per- mit improvements in the per for mance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the information being relied upon is current. Allegro’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the failure of that life support device or system, or to affect the safety or effectiveness of that device or system. The in for ma tion in clud ed herein is believed to be ac cu rate and reliable. How ev er, Allegro MicroSystems, Inc. assumes no re spon si bil i ty for its use; nor for any in fringe ment of patents or other rights of third parties which may result from its use.