ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor FEATURES AND BENEFITS • Industry-leading noise performance through proprietary amplifier and filter design techniques • Total output error 0.8% at TA = 25°C • Small package size, with easy mounting capability • Monolithic Hall IC for high reliability • Ultra-low power loss: 100 µΩ internal conductor resistance • 3 kVRMS minimum isolation voltage from pins 1-3 to pins 4-5 • 3.0 to 5.0 V, single supply operation • 3 µs output rise time in response to step input current • 20 or 40 mV/A output sensitivity • Output voltage proportional to AC or DC currents • Factory-trimmed for accuracy • Extremely stable output offset voltage • Nearly zero magnetic hysteresis TÜV America Certificate Number: U8V 14 05 54214 028 PACKAGE: UL Certified File No.: E316429 5-Pin CB Package (suffix PFF) DESCRIPTION The Allegro ACS756 family of current sensor ICs provides economical and precise solutions for AC or DC current sensing in industrial, automotive, commercial, and communications systems. The device package allows for easy implementation by the customer. Typical applications include motor control, load detection and management, power supplies, and overcurrent fault protection. The device consists of a precision, low-offset linear Hall circuit with a copper conduction path located near the die. Applied current flowing through this copper conduction path generates a magnetic field which the Hall IC converts 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 at the factory. The output of the device has a positive slope (>VCC / 2) when an increasing current flows through the primary copper conduction path (from terminal 4 to terminal 5), which is the path used for current sampling. The internal resistance of this conductive path is 100 µΩ typical, providing low power loss. The thickness of the copper conductor allows survival of the device at up to 5× overcurrent conditions. The terminals of the conductive path are electrically isolated from the signal leads Continued on the next page… 1 Additional leadforms available for qualifying volumes +5 V 4 VCC IP+ ACS756 IP GND 5 1 CBYP 0.1 µF 2 CF IP– VIOUT 3 RF Typical Application VOUT The ACS756 outputs an analog signal (VOUT ) that varies linearly with the uni- or bi-directional AC or DC primary sampled current, IP , within the range specified. CF is for optimal noise management, with values that depend on the application. ACS756xCB-DS, Rev. 2 ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor Description (continued) (pins 1 through 3). This allows the ACS756 family of sensor ICs to The device is fully calibrated prior to shipment from the factory. be used in applications requiring electrical isolation without the use The ACS75x family is lead (Pb) free. All leads are plated with 100% of opto-isolators or other costly isolation techniques. matte tin, and there is no Pb inside the package. The heavy gauge leadframe is made of oxygen-free copper. Selection Guide Part Number1 ACS756SCA-050B-PFF-T3 TOP (°C) Primary Sampled Current , IP (A) –20 to 85 ±50 ACS756SCB-050B-PFF-T –20 to 85 ±50 ACS756SCA-100B-PFF-T3 –20 to 85 ±100 ACS756SCB-100B-PFF-T –20 to 85 ±100 ACS756KCA-050B-PFF-T3 –40 to 125 ±50 ACS756KCB-050B-PFF-T –40 to 125 ±50 Packing2 34 per tube 1Additional leadform options available for qualified volumes for additional packing options. for new design. This classification indicates that sale of this device is currently restricted to existing customer applications. The device should not be purchased for new design applications because obsolescence in the near future is probable. 2Contact Allegro 3Not SPECIFICATIONS Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Forward Supply Voltage VCC 8 V Reverse Supply Voltage VRCC –0.5 V Forward Output Voltage VIOUT 28 V Reverse Output Voltage VRIOUT –0.5 V Working Voltage for Reinforced Isolation VWORKING-R Voltage applied between pins 1-3 and 4-5; tested at 3000 VAC for 1 minute according to UL standard 60950-1 353 VDC / Vpk Working Voltage for Basic Isolation VWORKING-B Voltage applied between pins 1-3 and 4-5; tested at 3000 VAC for 1 minute according to UL standard 60950-1 500 VDC / Vpk Output Source Current IOUT(Source) VIOUT to GND 3 mA IOUT(Sink) VCC to VIOUT Output Sink Current Nominal Operating Ambient Temperature Maximum Junction Storage Temperature TOP 1 mA Range K –40 to 125 ºC Range S –20 to 85 ºC TJ(max) 165 ºC Tstg –65 to 165 ºC Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor +5 V VCC IP+ Filter Dynamic Offset Cancellation To all subcircuits Amp Gain Out Temperature Coefficient VIOUT 0.1 µF Offset Trim Control IP– GND Functional Block Diagram Terminal List Table IP+ IP– 4 5 Number Name Description 3 VIOUT 2 GND 1 VCC Device power supply terminal 1 VCC 2 GND Signal ground terminal Pin-out Diagram 3 VIOUT 4 IP+ Analog output signal Terminal for current being sampled 5 IP– Terminal for current being sampled Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor COMMON OPERATING CHARACTERISTICS1 over full range of TOP, and VCC = 5 V, unless otherwise specified Characteristic Symbol Supply Voltage2 VCC Supply Current ICC Power On Time tPO Rise Time Internal Bandwidth3 tr BWi Test Conditions Min. Typ. Max. Units 3 5.0 5.5 V VCC = 5.0 V, output open – 10 14 mA TA = 25°C – 35 – µs IP = three-quarter scale of IP+, TA = 25°C, COUT = 0.47 nF – 3 – µs –3 dB; IP is 10 A peak-to-peak; 100 pF from VIOUT to GND – 120 – kHz Output Load Resistance RLOAD(MIN) VIOUT to GND 4.7 – – kΩ Output Load Capacitance CLOAD(MAX) VIOUT to GND – – 10 nF Primary Conductor Resistance Symmetry Bidirectional 0 A Output RPRIMARY ESYM VOUT(QBI) Over half-scale of Ip IP = 0 A, TA = 25°C – 100 – µΩ 98.5 100 101.5 % – VCC/2 – V IP = 0 A, after excursion of 100 A – ±0.20 – A Ratiometry VRAT VCC = 4.5 to 5.5 V – 100 – % Propagation Time tPROP TA = 25°C, COUT = 100 pF, – 1 – µs Magnetic Offset Error IERROM TA = 25°C 1 Device is factory-trimmed at 5 V, for optimal accuracy. 2 Devices are programmed for maximum accuracy at 5.0 V V CC 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 5 V VCC level. Customers that plan to operate the device from a 3.3 V regulated supply should contact their local Allegro sales representative regarding expected device accuracy levels under these bias conditions. 3 Guaranteed by design. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor ACS756xCB X050 PERFORMANCE CHARACTERISTICS over Range K1: TOP = –40°C to 125°C, VCC = 5 V, unless otherwise specified Characteristic Primary Sampled Current Sensitivity Noise2 Nonlinearity Electrical Offset Voltage3 Total Output Error4 Symbol Test Conditions IP SensTA SensTOP Half scale of IP applied for 5 ms, TA = 25°C Half scale of IP applied for 5 ms Min. Typ. Max. –50 – 50 Units A – 40 – mV/A 37.2 – 42.8 mV/A – 10 – mV % VNOISE TA= 25°C, 10 nF on VIOUT pin to GND ELIN(HT) Up to full scale of IP , IP applied for 5 ms, TOP = 25°C to 125°C –1 – 1 ELIN(LT) Up to full scale of IP , IP applied for 5 ms, TOP = –40°C to 25°C – 1.8 – 1.8 % VOE(TA) IP = 0 A, TA = 25°C – ±2 – mV VOE(TOP)HT IP = 0 A, TOP = 25°C to 125°C –30 – 30 mV VOE(TOP)LT IP = 0 A, TOP = –40°C to 25°C –60 – 60 mV ETOT(HT) Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 125°C –7.5 – 7.5 % ETOT(LT) Over full scale of IP , IP applied for 5 ms, TOP = –40°C to 25°C –7.5 – 7.5 % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TOP, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 26σ noise voltage. 3V OE(TOP) drift is referred to ideal VOE = 2.5 V at 0 A. 4Percentage of I , with I = 25 A. Output filtered. P P X050 PERFORMANCE CHARACTERISTICS over Range S1: TOP = –20°C to 85°C, VCC = 5 V, unless otherwise specified Characteristic Primary Sampled Current Sensitivity Noise2 Nonlinearity Electrical Offset Voltage3 Total Output Error4 Symbol Test Conditions IP SensTA SensTOP Half scale of IP applied for 5 ms, TA = 25°C Half scale of IP applied for 5 ms Min. Typ. Max. –50 – 50 Units A – 40 – mV/A 38.3 – 41.7 mV/A – 10 – mV % VNOISE TA= 25°C, 10 nF on VIOUT pin to GND ELIN(HT) Up to full scale of IP , IP applied for 5 ms, TOP = 25°C to 85°C –1 – 1 ELIN(LT) Up to full scale of IP , IP applied for 5 ms, TOP = –20°C to 25°C –1 – 1 % VOE(TA) IP = 0 A, TA = 25°C – ±2 – mV VOE(TOP)HT IP = 0 A, TOP = 25°C to 85°C –30 – 30 mV VOE(TOP)LT IP = 0 A, TOP = –20°C to 25°C –30 – 30 mV ETOT(HT) Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 85°C –5 – 5 % ETOT(LT) Over full scale of IP , IP applied for 5 ms, TOP = –20°C to 25°C –5 – 5 % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TOP, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 26σ noise voltage. 3V OE(TOP) drift is referred to ideal VOE = 2.5 V at 0 A. 4Percentage of I , with I = 25 A. Output filtered. P P Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 5 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor ACS756xCB X100 PERFORMANCE CHARACTERISTICS over Range S1: TOP = –20°C to 85°C, VCC = 5 V, unless otherwise specified Characteristic Primary Sampled Current Sensitivity Noise2 Nonlinearity Electrical Offset Voltage3 Total Output Error4 Symbol Test Conditions IP SensTA SensTOP Half scale of IP applied for 5 ms, TA = 25°C Half scale of IP applied for 5 ms Min. Typ. Max. –100 – 100 Units A – 20 – mV/A 18.2 – 21.8 mV/A – 6 – mV % VNOISE TA= 25°C, 10 nF on VIOUT pin to GND ELIN(HT) Up to full scale of IP , IP applied for 5 ms, TOP = 25°C to 85°C – 1.75 – 1.75 ELIN(LT) Up to full scale of IP , IP applied for 5 ms, TOP = –20°C to 25°C –1 – 1 % VOE(TA) IP = 0 A, TA = 25°C – ±2 – mV VOE(TOP)HT IP = 0 A, TOP = 25°C to 85°C –30 – 30 mV VOE(TOP)LT IP = 0 A, TOP = –20°C to 25°C –30 – 30 mV ETOT(HT) Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 85°C –8 – 8 % ETOT(LT) Over full scale of IP , IP applied for 5 ms, TOP = –20°C to 25°C –7 – 7 % 1Device may be operated at higher primary current levels, IP, and ambient temperatures, TOP, provided that the Maximum Junction Temperature, TJ(max), is not exceeded. 26σ noise voltage. 3V OE(TOP) drift is referred to ideal VOE = 2.5 V at 0 A. 4Percentage of I , with I = 25 A. Output filtered. P P Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor DEFINITIONS OF ACCURACY CHARACTERISTICS Sensitivity (Sens) The change in device 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 half-scale current of the device. Noise (VNOISE) 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. Nonlinearity (ELIN) The degree to which the voltage output from the IC varies in direct proportion to the primary current through its half-scale amplitude. Nonlinearity in the output can be attributed to the saturation of the flux concentrator approaching the half-scale current. The following equation is used to derive the linearity: { [ 100 1– ∆ gain × % sat ( VIOUT_half-scale amperes –VIOUT(Q) ) 2 (VIOUT_quarter-scale amperes – VIOUT(Q) ) [{ where ∆ gain = the gain variation as a function of temperature changes from 25ºC, % sat = the percentage of saturation of the flux concentrator, which becomes significant as the current being sampled approaches half-scale ±IP , and VIOUT_half-scale amperes = the output voltage (V) when the sampled current approximates half-scale ±IP . Symmetry (ESYM) The degree to which the absolute voltage output from the IC varies in proportion to either a positive or negative half-scale primary current. The following equation is used to derive symmetry: 100 VIOUT_+ half-scale amperes – VIOUT(Q) VIOUT(Q) – VIOUT_–half-scale amperes Ratiometry The device features a ratiometric output. This means that the quiescent voltage output, VIOUTQ, and the magnetic sensitivity, Sens, are proportional to the supply voltage, VCC. The ratiometric change (%) in the quiescent voltage output is defined as: ∆VIOUTQ(∆V) = VIOUTQ(VCC) VIOUTQ(5V) VCC 5V × 100% and the ratiometric change (%) in sensitivity is defined as: ∆Sens(∆V) = Sens(VCC) VCC Sens(5V) 5V × 100% Quiescent output voltage (VIOUT(Q)) The output of the device 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 VOUT(Q) can be attributed to the resolution of the Allegro linear IC quiescent voltage trim, magnetic hysteresis, and thermal drift. Electrical offset voltage (VOE) The deviation of the device output from its ideal quiescent value of VCC ⁄ 2 due to nonmagnetic causes. Magnetic offset error (IERROM) The magnetic offset is due to the residual magnetism (remnant field) of the core material. The magnetic offset error is highest when the magnetic circuit has been saturated, usually when the device has been subjected to a full-scale or high-current overload condition. The magnetic offset is largely dependent on the material used as a flux concentrator. The larger magnetic offsets are observed at the lower operating temperatures. Total Output Error (ETOT) The maximum deviation of the actual output from its ideal value, also referred to as accuracy, illustrated graphically in the output voltage versus current chart on the following page. ETOT is divided into four areas: • 0 A at 25°C. Accuracy at the zero current flow at 25°C, without the effects of temperature. • 0 A over Δ temperature. Accuracy at the zero current flow including temperature effects. • Half-scale current at 25°C. Accuracy at the the half-scale current at 25°C, without the effects of temperature. • Half-scale current over Δ temperature. Accuracy at the half-scale current flow including temperature effects. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor ACS756xCB 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 device 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 device, in which ƒ(–3 dB) = 0.35 / tr. Both tr and tRESPONSE are detrimentally affected by eddy current losses observed in the conductive IC ground plane. Propagation Delay (tPROP) The time required for the device output to reflect a change in the primary current signal. Propagation delay is attributed to inductive loading within the linear IC package, as well as in the inductive loop formed by the primary conductor geometry. Propagation delay can be considered as a fixed time offset and may be compensated. Increasing VIOUT(V) Power-On TIme (tPO) I (%) 90 Transducer Output 10 0 Rise Time, tr Accuracy Over ∆Temp erature t Rise TIme (tr) Accuracy 25°C Only Average VIOUT I (%) Accuracy Over ∆Temp erature IP(min) Primary Current Primary Current 90 Accuracy 25°C Only –IP (A) +IP (A) Half Scale Transducer Output IP(max) 0A 0 Propagation Time, tPROP Accuracy 25°C Only t Propagation Delay (tPROP) Accuracy Over ∆Temp erature Decreasing VIOUT(V) Output Voltage versus Sampled Current Total Output Error at 0 A and at Half-Scale Current Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor CHOPPER STABILIZATION TECHNIQUE Chopper Stabilization is an innovative circuit technique that is used to minimize the offset voltage of a Hall element and an associated on-chip amplifier. Allegro patented a Chopper Stabilization 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 temperature and mechanical stress. This technique produces devices that have an extremely stable Electrical Offset Voltage, 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. Regulator Clock/Logic Amp Sample and Hold Hall Element Low-Pass Filter Concept of Chopper Stabilization Technique Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor ACS756xCB PACKAGE OUTLINE DRAWING For Reference Only – Not for Tooling Use (Reference DWG-9111 & DWG-9110) Dimensions in millimeters – NOT TO SCALE Dimensions exclusive of mold flash, gate burs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown 14.0 ±0.2 0.5 3.5 ±0.2 4.0 ±0.2 3.0 ±0.2 R3 1º±2° 1.50 ±0.10 5 R1 R2 4 A ∅ 0.5 B 3 17.5 ±0.2 4 21.4 13.00 ±0.10 Branded Face 4.40 ±0.10 ∅ 0.8 1.9 ±0.2 ∅ 1.5 2.9 ±0.2 0.51 ±0.10 1 2 3 0.381 +0.060 –0.030 1.91 5º±5° 10.00 ±0.10 B PCB Layout Reference View 3.5 ±0.2 NNNNNNN TTT-AAA 7.00 ±0.10 LLLLLLL A Dambar removal intrusion YYWW B Perimeter through-holes recommended C Branding scale and appearance at supplier discretion 1 C Standard Branding Reference View N T A L Y = Device part number = Temperature code = Amperage range = Lot number = Last two digits of year of manufacture W = Week of manufacture = Supplier emblem Package CB, 5-Pin, Leadform PFF Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 ACS756xCB Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor Revision History Revision Revision Date – December 16, 2014 1 February 9, 2015 2 June 4, 2015 Description of Revision Initial Release Added TUV/UL Certification info Added CA package NND information and CB package to selection guide Copyright ©2006-2015, Allegro MicroSystems, LLC The products described herein are protected by U.S. patents: 6,781,359; and 7,265,531. 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 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 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 11