ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for <100 V Isolation Applications FEATURES AND BENEFITS * No external sense resistor required; single package solution * Reduced power loss: 0.6 m internal conductor resistance on EX package 1.2 m internal conductor resistance on LC package * * * * * * * * * * * * * * Economical low- and high-side current sensing Output voltage proportional to AC or DC currents 12.5 A and 25 A full-scale sensing ranges on LC package 15.5 A and 31 A full-scale sensing ranges on EX package AULT trips and latches at 100% of full-scale Overcurrent F current Low-noise analog signal path 100 kHz bandwidth Small footprint, low-profile SOIC8 and QFN packages 3 to 5.5 V single supply operation Integrated electrostatic shield for output stability Factory-trimmed for accuracy Extremely stable output offset voltage Zero magnetic hysteresis Ratiometric output from supply voltage PACKAGES: The AllegroTM ACS711 provides economical and precise solutions for AC or DC current sensing in <100 V audio, communications systems, and white goods. The device package allows for easy implementation by the customer. Typical applications include circuit protection, current monitoring, and motor and inverter control. The device consists of a 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. The output of the device has a positive slope proportional to the current flow from IP+ to IP- (pins 1 and 2, to pins 3 and 4). The internal resistance of this conductive path is 0.6 m for the EX package, and 1.2 m for the LC package, providing a non-intrusive measurement interface that saves power in applications that require energy efficiency. The ACS711 is optimized for low-side current sensing applications, although the terminals of the conductive path are electrically isolated from the sensor IC leads, providing sufficient internal creepage and clearance dimensions for a low AC or DC working voltage applications. The thickness of the copper conductor allows survival of the device at up to 12-contact QFN 3 mm x 3 mm x 0.75 mm (EX package) 8-pin SOICN with internally fused path (LC package) DESCRIPTION Continued on the next page... Not to scale Typical Application +3.3 V IP+ VCC CBYP 0.1 F IP+ VIOUT IP ACS711 IP- IP- ACS711A-DS, Rev. 4 FAULT RPU CLOAD Application 1. The ACS711 outputs an analog signal, VIOUT , that varies linearly with the bi-directional AC or DC primary current, IP , within the range specified. The FAULT pin trips when IP reaches 100% of its fullscale current. GND June 23, 2017 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 DESCRIPTION (CONTINUED) 5x overcurrent conditions. assembly processes. Internally, the device is Pb-free, except for flip-chip high-temperature Pbbased solder balls, currently exempt from RoHS. The device is fully calibrated prior to shipment from the factory. The ACS711 is provided in small, surface-mount packages: SOIC8 and QFN12. The leadframe is plated with 100% matte tin, which is compatible with standard lead (Pb) free printed circuit board SELECTION GUIDE TA (C) Part Number ACS711ELCTR-12AB-T -40 to 85 ACS711KLCTR-12AB-T -40 to 125 ACS711ELCTR-25AB-T -40 to 85 ACS711KLCTR-25AB-T -40 to 125 ACS711EEXLT-31AB-T [3][4] -40 to 85 ACS711KEXLT-31AB-T [3] -40 to 125 ACS711EEXLT-15AB-T [3][4] -40 to 85 ACS711KEXLT-15AB-T [3] -40 to 125 Optimized Accuracy Range, IP (A) Sensitivity [2], Sens (Typ) (mV/A) 12.5 110 25 55 31 45 15.5 90 Package Packing [1] 8-pin SOICN 3000 pieces/reel 12-contact QFN with fused current loop 1500 pieces/reel [1] Contact Allegro for additional packing options. measured with VCC = 3.3 V. [3] QFN package not qualified for automotive applications. [4] Variants ACS711EEXLT-15AB-T and ACS711EEXLT-31AB-T are Pre-End-of-Life. These device variants are approaching end of life. Within a minimum of 6 months, these device variants will enter their final, Last Time Buy, order phase. Date of status change: June 5, 2017. Suggested replacements include ACS711KEXLT-15AB-T and ACS711KEXLT-31AB-T, respectively. [2] Sensitivity ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Notes Rating Units Supply Voltage VCC 7 V Reverse Supply Voltage VRCC -0.1 V Output Voltage VIOUT 7 V Reverse Output Voltage VRIOUT -0.1 V Voltage applied between pins 1-4 and 5-8 100 VAC peak or VDC 7 V 1 pulse, 100 ms 100 A Range E -40 to 85 C Range K -40 to 125 C TJ(max) 165 C Tstg -65 to 170 C Working Voltage for Basic Isolation FAULT Pin Voltage Overcurrent Transient Tolerance Nominal Operating Ambient Temperature Maximum Junction Temperature Storage Temperature VWORKING VFAULT IPOC TA Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Functional Block Diagram VCC VCC RPU Master Current Supply Current Fault Comparator To all subcircuits D Power-on Reset IP+ Hall Current Drive CBYP FAULT 240 k Reset Sensitivity Temperature Coefficient Trim Dynamic Offset Cancellation IP+ IP- VIOUT Signal Recovery CLOAD Sensitivity Trim 0 Ampere Offset Adjust IP- GND VCC VIOUT 12 11 PINOUT DIAGRAMS 1 8 VCC NC IP+ 2 7 VIOUT IP- 3 8 NC IP- 3 6 FAULT IP- 4 7 NC IP- 4 5 GND 6 IP+ 9 5 10 NC 2 GND 1 IP+ FAULT IP+ EX Package LC Package TERMINAL LIST TABLE Name Number EX LC Description GND 5 5 Signal ground terminal FAULT 6 6 Overcurrent fault; active low IP- 3 and 4 3 and 4 Terminals for current being sensed; fused internally IP+ 1 and 2 1 and 2 Terminals for current being sensed; fused internally NC 7, 8, 9, 10 - No connection; connect to GND for optimal ESD performance. VCC 12 8 Device power supply terminal VIOUT 11 7 Analog output signal Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications COMMON OPERATING CHARACTERISTICS: Valid across the full range of TA for the LC package and at TA = 25C for the EX package, VCC = 3.3 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Units ELECTRICAL CHARACTERISTICS Supply Voltage [1] VCC Supply Current ICC 3 3.3 5.5 V VCC = 3.3 V, output open - 4 5.5 mA - 1 nF Output Capacitance Load CLOAD VIOUT to GND - Output Resistive Load RLOAD VIOUT to GND 15 - - k EX package - 0.6 - m Primary Conductor Resistance VIOUT Rise Time Propagation Delay Time Response Time Internal Bandwidth [2] RIP LC package, TA = 25C - 1.2 - m IP = IPMAX, TA = 25C, COUT = open - 3.5 - s tPROP IP = IP(max), TA = 25C, COUT = open - 1.2 - s tRESPONSE IP = IP(max), TA = 25C, COUT = open - 4.6 - s tr BWI -3 dB, TA = 25C - 100 - kHz Nonlinearity ELIN Over full range of IP - 1 - % Symmetry ESYM Apply full scale IP VIOUT Saturation Voltages Quiescent Output Voltage Power-On Time - 100 - % VIOH VCC - 0.3 - - V VIOL - - 0.3 V IP = 0 A, TA = 25C - VCC / 2 - V Output reaches 90% of steady-state level, TA = 25C, 20 A present on primary conductor - 35 - s IFAULT - 1 x IP - A RPU 1 - - k VOH - VCC - 0.3 - V RPU = 1 k - 0.3 - V Measured from | IP | > | IFAULT | to VFAULT VOL - 1.3 - s VIOUT(Q) tPO AULT PIN CHARACTERISTICS F FAULT Operating Point AULT Output Pullup F Resistor AULT Output Voltage F VOL FAULT Response Time tFAULT VCC Off Voltage Level for Fault Reset [3] VCCFR - - 200 mV VCC Off Duration for Fault Reset [3] tCCFR 100 - - s [1] Devices are programmed for maximum accuracy at 3.3 V VCC levels. The device contains ratiometry circuits that accurately alter the 0 A Output Voltage and Sensitivity level of the device in proportion to the applied VCC level. However, as a result of minor nonlinearities in the ratiometry circuit additional output error will result when VCC varies from the 3.3 V VCC level. Customers that plan to operate the device from a 5 V regulated supply should contact their local Allegro sales representative regarding expected device accuracy levels under these bias conditions. [2] Calculated using the formula BW = 0.35 / t . I r [3] After the F AUL T pin is latched low, the only way to reset it is through a power-off and power-on cycle on the VCC pin. For fault reset, VCC must stay below VCCFR for a period greater than tCCFR before settling to the normal operation voltage (3 to 5.5 V). Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications x12AB PERFORMANCE CHARACTERISTICS for LC package and E Temperature Range [1] TA = 25C and VCC = 3.3 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Electrical Offset Voltage Error [3] Test Conditions IP Sens Noise [1] Total Output Symbol Min. Typ. Max. Units -12.5 - 12.5 A Over full range of IP - 110 - mV/A Full scale of IP applied for 5 ms, TA = -40C to 25C - 110 - mV/A mV/A Full scale of IP applied for 5 ms, TA = 25C to 85C - 110 - VNOISE TA = 25C, no external low pass filter on VIOUT - 11 - mV VOE(TA) IP = 0 A, TA = 25C - 5 - mV VOE(TOP)HT IP = 0 A, TA = 25C to 85C - 40 - mV VOE(TOP)LT IP = 0 A, TA = -40C to 25C - 50 - mV IP = 12.5 A,TA = -40C to 85C - 5 - % Typ. Max. Units ETOT [1] See Characteristic Performance Data for parameter distributions over temperature. sigma noise voltage. [3] Percentage of I , with I = 12.5 A. P P [2] 3 x12AB PERFORMANCE CHARACTERISTICS for LC package and K Temperature Range [1] TA = 25C and VCC = 3.3 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Noise [2] Electrical Offset Voltage Total Output Error [3] Symbol Test Conditions Min. -12.5 - 12.5 A Over full range of IP - 110 - mV/A IP Full scale of IP applied for 5 ms, TA = -40C to 25C - 110 - mV/A Full scale of IP applied for 5 ms, TA = 25C to 125C - 110 - mV/A VNOISE TA = 25C, no external low pass filter on VIOUT - 11 - mV VOE(TA) IP = 0 A, TA = 25C - 5 - mV VOE(TOP)HT IP = 0 A, TA = 25C to 125C - 40 - mV VOE(TOP)LT IP = 0 A, TA = -40C to 25C - 50 - mV IP = 12.5 A,TA = -40C to 125C - 5 - % Min. Typ. Max. Units -15.5 - 15.5 A - 90 - mV/A Sens ETOT [1] See Characteristic Performance Data for parameter distributions over temperature. sigma noise voltage. [3] Percentage of I , with I = 12.5 A. P P [2] 3 x15AB PERFORMANCE CHARACTERISTICS[1] TA = 25C and VCC = 3.3 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Noise [2] Electrical Offset Voltage Total Output Error [3] Symbol Test Conditions IP Sens Across full range of IP VNOISE No external low pass filter on VIOUT - 11 - mV VOE(TA) IP = 0 A - 5 - mV VOE(TOP)HT IP = 0 A, TA = 25C to TA(max) - 40 - mV VOE(TOP)LT IP = 0 A, TA = -40C to 25C - 50 - mV IP = 12.5 A,TA = -40C to TA(max) - 5 - % ETOT [1] See Characteristic Performance Data for parameter distributions across the full temperature range. sigma noise voltage. [3] Percentage of I , with I = 15.5 A. P P [2] 3 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 5 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications x25AB PERFORMANCE CHARACTERISTICS for for LC package and E Temperature Range [1] TA = 25C and VCC = 3.3 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Electrical Offset Voltage Error [3] Test Conditions IP Sens Noise [2] Total Output Symbol Min. Typ. Max. Units -25 - 25 A Over full range of IP - 55 - mV/A Full scale of IP applied for 5 ms, TA = -40C to 25C - 55 - mV/A Full scale of IP applied for 5 ms, TA = 25C to 85C - 55 - mV/A VNOISE TA = 25C, no external low pass filter on VIOUT - 8 - mV VOE(TA) IP = 0 A, TA = 25C - 5 - mV VOE(TOP)HT IP = 0 A, TA = 25C to 85C - 30 - mV VOE(TOP)LT IP = 0 A, TA = -40C to 25C - 35 - mV IP =25 A, TA = -40C to 85C - 4 - % Min. Typ. Max. Units -25 - 25 A ETOT [1] See Characteristic Performance Data for parameter distributions over temperature. sigma noise voltage. [3] Percentage of I , with I = 25 A. P P [2] 3 x25AB PERFORMANCE CHARACTERISTICS for LC package and K Temperature Range [1] TA = 25C and VCC = 3.3 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Electrical Offset Voltage Error [3] Test Conditions IP Sens Noise [2] Total Output Symbol Over full range of IP - 55 - mV/A Full scale of IP applied for 5 ms, TA = -40C to 25C - 55 - mV/A mV/A Full scale of IP applied for 5 ms, TA = 25C to 125C - 55 - VNOISE TA = 25C, no external low pass filter on VIOUT - 8 - mV VOE(TA) IP = 0 A, TA = 25C - 5 - mV VOE(TOP)HT IP = 0 A, TA = 25C to 125C - 30 - mV VOE(TOP)LT IP = 0 A, TA = -40C to 25C - 35 - mV IP =25 A, TA = -40C to 125C - 4 - % Min. Typ. Max. Units -31 - 31 A - 45 - mV/A ETOT [1] See Characteristic Performance Data for parameter distributions over temperature. sigma noise voltage. [3] Percentage of I , with I = 25 A. P P [2] 3 x31AB PERFORMANCE CHARACTERISTICS[1] TA = 25C and VCC = 3.3 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Noise [2] Electrical Offset Voltage Total Output Error [3] Symbol Test Conditions IP Sens Across full range of IP VNOISE No external low pass filter on VIOUT - 8 - mV VOE(TA) IP = 0 A - 5 - mV VOE(TOP)HT IP = 0 A, TA = 25C to TA(max) - 30 - mV VOE(TOP)LT IP = 0 A, TA = -40C to 25C - 35 - mV IP =25 A, TA = -40C to TA(max) - 4 - % ETOT [1] See Characteristic Performance Data for parameter distributions across the full temperature range. sigma noise voltage. [3] Percentage of I , with I = 31 A. P P [2] 3 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications THERMAL CHARACTERISTICS Characteristic Package Thermal Resistance, Junction to Lead Package Thermal Resistance, Junction to Ambient [2] Symbol Test Conditions [1] Value Units RJL LC package, mounted on Allegro ASEK 711 evaluation board 5 C/W LC package, mounted on Allegro 85-0404 evaluation board, includes the power consumed by the board 23 C/W EX package, mounted on Allegro 85-0528 evaluation board, includes the power consumed by the board 24 C/W RJA [1] Additional thermal information available on the Allegro website. 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 connecting 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. [2] The Allegro Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Characteristic Performance Data Data taken using the ACS711KEX-15A, VCC = 3.3 V QVO versus Ambient Temperature QVO Error versus Ambient Temperature 1720 60 1700 40 VOE (mV) QVO (mV) 1680 1660 1640 1620 0 -20 -40 1600 1580 20 -60 -40 -20 0 20 40 60 -60 80 100 120 140 -60 -40 -20 0 TA (C) Sensitivity versus Ambient Temperature 80 100 120 140 Total Error versus Ambient Temperature 4 92 2 90 0 ETOT (%) Sensitivity (mV/A) 60 6 88 86 -2 -4 -6 84 -8 -60 -40 -20 0 20 40 60 -10 80 100 120 140 -60 -40 -20 0 TA (C) 0.6 100.4 0.5 100.3 0.4 100.1 100 99.9 0.1 0 99.7 -0.1 20 40 80 100 120 140 0.2 99.8 0 60 0.3 ELIN (%) 100.2 -60 -40 -20 40 Nonlinearity versus Ambient Temperature 100.5 99.6 20 TA (C) Symmetry versus Ambient Temperature ESYM (%) 40 TA (C) 94 82 20 60 80 100 120 140 -0.2 TA (C) -60 -40 -20 0 20 40 60 80 100 120 140 TA (C) Typical Maximum Limit Mean Typical Minimum Limit Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Characteristic Performance Data Data taken using the ACS711KEX-31AB, VCC = 3.3 V 1700 1690 1680 1670 1660 1650 1640 1630 1620 1610 1600 QVO Error versus Ambient Temperature VOE (mV) QVO(mV) QVO versus Ambient Temperature -60 -40 -20 0 20 40 60 80 100 120 140 50 40 30 20 10 0 -10 -20 -30 -40 -50 -60 -40 -20 0 20 TA (C) 80 100 120 140 15 10 5 0 -5 -10 -60 -40 -20 0 20 40 60 TA (C) -15 80 100 120 140 -60 -40 -20 ELIN(%) 101 100.8 100.6 100.4 100.2 100 99.8 99.6 99.4 99.2 99 -60 -40 -20 0 20 40 60 80 100 120 140 0 20 40 60 TA (C) 80 100 120 140 Nonlinearity versus Ambient Temperature Symmetry versus Ambient Temperature ESYM(%) 60 Total Error versus Ambient Temperature ETOT(%) Sensitivity (mV/A) Sensitivity versus Ambient Temperature 50 49 48 47 46 45 44 43 42 41 40 40 TA (C) 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1 TA (C) -60 -40 -20 0 20 40 60 80 100 120 140 TA (C) Typical Maximum Limit Mean Typical Minimum Limit Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Characteristic Performance Data Data taken using the ACS711KLC-12A, VCC = 3.3 V Accuracy Data Electrical Offset Voltage versus Ambient Temperature 114 60 113 Sens (mV/A) 80 40 VOE (mV) Sensitivity versus Ambient Temperature 20 0 112 111 110 -20 109 -40 108 -60 -60 -40 -20 0 20 40 60 80 100 120 107 -60 140 -40 -20 0 20 TA (C) Nonlinearity versus Ambient Temperature 101.5 1.5 101.0 ESYM (%) ELIN (%) 1.0 0.5 0 100 120 140 100.5 100.0 99.0 -1.0 -1.5 -40 -20 0 20 40 60 80 100 120 98.5 -60 140 -40 -20 0 20 40 60 80 100 120 140 TA (C) TA (C) Total Output Error versus Ambient Temperature Fault Operating Point versus Ambient Temperature 8 16 6 14 4 12 2 IFAULT(A) ETOT (%) 80 99.5 -0.5 0 -2 10 8 6 4 -4 -6 -60 60 Symmetry versus Ambient Temperature 2.0 -60 40 TA (C) 2 -40 -20 0 20 40 60 80 100 120 0 140 -60 TA (C) -40 -20 0 20 40 60 80 100 120 140 TA (C) Typical Maximum Limit Mean Typical Minimum Limit Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Characteristic Performance Data Data taken using the ACS711KLC-25A, VCC = 3.3 V Accuracy Data Electrical Offset Voltage versus Ambient Temperature 40 57.0 30 56.5 Sens (mV/A) 20 VOE (mV) Sensitivity versus Ambient Temperature 10 0 -10 55.5 55.0 54.5 -20 54.0 -30 -40 -60 56.0 -40 -20 0 20 40 60 80 100 120 53.5 -60 140 -40 -20 0 20 TA (C) Nonlinearity versus Ambient Temperature 120 140 100.4 0.5 ESYM (%) ELIN (%) 100 100.6 0 -0.5 100.2 100.0 99.8 99.6 99.4 -1.0 99.2 99.0 -40 -20 0 20 40 60 80 100 120 140 -60 -40 -20 0 20 40 60 80 100 120 140 TA (C) TA (C) Total Output Error versus Ambient Temperature Fault Operating Point versus Ambient Temperature 5 30 4 25 3 2 20 1 IFAULT (A) ETOT (%) 80 100.8 1.0 0 -1 -2 15 10 5 -3 -4 -60 60 Symmetry versus Ambient Temperature 1.5 -1.5 -60 40 TA (C) -40 -20 0 20 40 60 80 100 120 0 140 -60 TA (C) -40 -20 0 20 40 60 80 100 120 140 TA (C) Typical Maximum Limit Mean Typical Minimum Limit Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications Characteristic Performance Data Data taken using the ACS711KLC-25A Timing Data Rise Time Propagation Delay Time VIOUT (0.5 V/div.) VIOUT (0.5 V/div.) IP (10 A/div.) IP (10 A/div.) 3.47 s 1.24 s t (2 s/div.) t (2 s/div.) Response Time Fault Response VIOUT (0.5 V/div.) IP (10 A/div.) 4.62 s IP (10 A/div.) 1.28 s Fault (2 V/div.) t (2 s/div.) t (2 s/div.) Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 12 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications DEFINITIONS OF ACCURACY CHARACTERISTICS 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 programmed at the factory to optimize the sensitivity (mV/A) for the full-scale current of the device. Noise (VNOISE). The product of the linear IC amplifier gain (mV) and the noise floor for the Allegro Hall effect linear IC. 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. Accuracy (ETOT). The accuracy represents the maximum deviation 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 below. Ratiometry. The ratiometric feature means that its 0 A output, VIOUT(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, VIOUT(Q)RAT (%): The ratiometric change in sensitivity, SensRAT (%), is defined as: Linearity (ELIN). 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: { [ 100 1- gain x % sat ( VIOUT_full-scale amperes - VIOUT(Q) ) 2 (VIOUT_half-scale amperes - VIOUT(Q) ) 100 VIOUT(Q)VCC / VIOUT(Q)3.3V 100 [{ SensVCC / Sens3.3V VCC / 3.3 V Accuracy at 0 A and at Full-Scale Current Increasing VIOUT(V) Symmetry (ESYM). The degree to which the absolute voltage output from the sensor varies in proportion to either a positive or negative full-scale primary current. The following formula is used to derive symmetry: VIOUT_+ full-scale amperes - VIOUT(Q) VIOUT(Q) - VIOUT_-full-scale amperes Electrical offset voltage (VOE). The deviation of the device output 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 Over Temp erature Accuracy 25C Only Average VIOUT 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 = 3.3 V translates into VIOUT(Q) = 1.65 V. Variation in VIOUT(Q) can be attributed to the resolution of the Allegro linear IC quiescent voltage trim and thermal drift. Output Voltage versus Sensed Current where VIOUT_full-scale amperes = the output voltage (V) when the sensed current approximates full-scale IP . 100 VCC / 3.3 V Accuracy Over Temp erature IP(min) Accuracy 25C Only -IP (A) +IP (A) Full Scale IP(max) 0A Accuracy 25C Only Accuracy Over Temp erature Decreasing VIOUT(V) Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 13 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications DEFINITIONS OF DYNAMIC RESPONSE CHARACTERISTICS Power-On Time (tPO). When the supply is ramped to its operating voltage, the device requires a finite time to power its internal components before responding to an input magnetic field. Power-On Time, tPO , 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, VCC(min), as shown in the chart at right. 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 (-3 dB) = 0.35 / tr. Both tr and tRESPONSE are detrimentally affected by eddy current losses observed in the conductive IC ground plane. I (%) Primary Current 90 Transducer Output 10 0 Rise Time, tr t Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 14 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 APPLICATION INFORMATION Layout To optimize thermal and electrical performance, the following features should be included in the printed circuit board: * The primary leads should be connected to as much copper area as is available. * The copper should be 2 oz. or heavier. * The two solder pads at the ends of the exposed pad loop should be placed directly on the copper trace that conducts the primary current. * When using vias under exposed pads, such as with the EX package, using plugged vias prevents wicking of the solder from the pad into the via during reflow. Whether or not to use plugged vias should be evaluated in the application. * Additional layers of the board should be used for conducting the primary current if possible, and should be connected using the arrangement of vias shown below. Solder pads Signal traces EX package footprint Exposed pad loop Via under pad Via Primary Current Trace Primary Current Trace Suggested Layout. EX package shown. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 15 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Package LC, 8-pin SOIC 4.90 0.10 8 0 8 0.65 3.90 0.10 1 6.00 0.20 2 0.25 BSC Branded Face SEATING PLANE 0.10 C 0.51 0.31 1.27 BSC 5.60 1.04 REF 1 1.27 0.40 8X C 1.27 1.75 0.25 0.17 A 8 C 2 PCB Layout Reference View SEATING PLANE GAUGE PLANE NNNNNNN TPP-AAA LLLLL 1.75 MAX 0.25 0.10 1 B Standard Branding Reference View For Reference Only; not for tooling use (reference MS-012AA) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown A Terminal #1 mark area B Branding scale and appearance at supplier discretion C D N = Device part number T = Device temperature range P = Package Designator A = Amperage L = Lot number Belly Brand = Country of Origin Reference land pattern layout (reference IPC7351 SOIC127P600X175-8M); all pads a minimum of 0.20 mm from all adjacent pads; adjust as necessary to meet application process requirements and PCB layout tolerances Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 16 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications ACS711 Package EX, 12-Contact QFN With Fused Sensed Current Loop 3.00 BSC 0.85 12 1 1.27 MIN 0.30 12 1 A 2 3.00 BSC 2.90 1.00 0.80 MIN Branded Face 9X 0.50 D SEATING PLANE 0.08 C 0.50 BSC C 0.70 2.05 REF 0.75 0.05 C 2.70 PCB Layout Reference View +0.05 0.25 -0.07 1 1.79 0.400.10 B 0.20 NNNN YYWW LLLL 2 1 E 12 For reference only, not for tooling use (reference JEDEC MO-220WEED except for fused current path) Dimensions in millimeters Exact case and lead configuration at supplier discretion within limits shown A Terminal #1 mark area B Fused sensed current path Standard Branding Reference View N = Device part number Y = Last two digits of year of manufacture W = Week of manufacture L = Lot number C Reference land pattern layout (reference IPC7351 QFN50P300X300X80-17W4M); All pads a minimum of 0.20 mm from all adjacent pads; adjust as necessary to meet application process requirements and PCB layout tolerances; when mounting on a multilayer PCB, thermal vias at the exposed thermal pad land can improve thermal dissipation (reference EIA/JEDEC Standard JESD51-5) D Coplanarity includes exposed current path and terminals E Branding scale and appearance at supplier discretion Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 17 ACS711 Hall-Effect Linear Current Sensor with Overcurrent Fault Output for < 100 V Isolation Applications Revision History Number Date 2 July 18, 2013 3 February 6, 2015 4 June 23, 2017 Description Update characteristics tables references Revised NC description in Terminal List Table Added ACS711KEX-15A and ACS711KEX-31AB characteristic performance data plots; Revised product status of ACS711EEXLT-15AB-T and ACS711EEXLT-31AB-T variants to Pre-End-of-Life. Copyright (c)2017, Allegro MicroSystems, LLC Allegro MicroSystems, LLC reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, 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 any devices or systems, including but not limited to life support devices or systems, in which a failure of Allegro's product can reasonably be expected to cause bodily harm. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, LLC assumes no responsibility for its use; nor for any infringement of patents or other rights of third parties which may result from its use. For the latest version of this document, visit our website: www.allegromicro.com Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 18