ACHS-7122-000E

Data Sheet ACHS-7121/7122/7123 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor Overview Features The Broadcom® ACHS-7121/7122/7123 product series is a fully integrated Hall Effect-based isolated linear current sensor device family designed for AC or DC current sensing in industrial, commercial, and communications systems. Each of the ACHS-7121/7122/7123 consists of a precise, low-offset, linear Hall 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 that 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 CMOS Hall IC, which is programmed for accuracy after packaging. The output of the device has a positive slope (>VOUT(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 sampling.                 The internal resistance of this conductive path is 0.7 mΩ typical, providing low-power loss. The terminals of the conductive path are electrically isolated from the signal leads (pins 5 through 8). This performance is delivered in a compact, surface mountable, SO-8 package that meets worldwide regulatory safety standards. Wide operating temperature: –40ºC to 110ºC Primary conductor resistance: 0.7 mΩ typ. Sensing current range: ±10A, ±20A, and ±30A Output sensitivity: 66 to 185 mV/A Output voltage proportional to AC or DC currents Ratiometric output from supply voltage Single supply operation: 5.0V Low-noise analog signal path Device bandwidth is set via FILTER pin: 80 kHz typ. Bandwidth with 1-nF filter capacitor Factory-trimmed for accuracy Extremely stable output offset voltage Near zero magnetic hysteresis Typical total output error of ±1.5% >25 kV/μs Common-Mode Transient Immunity Small footprint, low-profile SO-8 package Worldwide Safety Approval: UL, CSA: Isolation Voltage 3 kVRMS, 1 minute Applications    Part Number Current Range Sensitivity  ACHS-7121 ±10A 185 mV/A  ACHS-7122 ±20A 100 mV/A ACHS-7123 ±30A 66 mV/A Low-power inverter current sensing Motor phase and rail current sensing Solar inverters Chargers and converters Switching power supplies CAUTION! It is advised that normal static precautions be taken in handling and assembly of this component to prevent damage and/or degradation which may be induced by ESD. The components featured in this data sheet are not to be used in military or aerospace applications or environments. The component is not AEC-Q100 qualified and not recommended for automotive applications. Broadcom ACHS-712x-DS103 October 28, 2020 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Functional Diagram I P+ 1 8 VDD I P+ I P– I P– 2 7 3 6 4 5 VOUT FILTER GND NOTE: The connection of 1-μF bypass capacitor between pins 8 and 5 is recommended. Pin Description Pin Pin Name Description Pin Pin Name Description 1 IP+ 8 VDD Supply voltage relative to GND 2 IP+ Terminals for current being sampled; fused internally 7 VOUT Output Voltage 3 IP– 6 FILTER Filter pin to set bandwidth 4 IP– Terminals for current being sampled; fused internally 5 GND Output side ground Typical Application Circuit A typical application circuit for the ACHS-7121/7122/7123 product series consists of a bypass capacitor and a filter capacitor as additional external components. On the input side, pins 1 and 2 are shorted together and pins 3 and 4 shorted together. The output voltage is directly measured from the VOUT pin. 5V I P+ I P– Broadcom I P+ VDD I P+ I P– I P– VOUT FILTER GND CBYPASS OUTPUT CF ACHS-712x-DS103 2 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Ordering Information Option Part Number ACHS-7121 ACHS-7122 ACHS-7123 UL 3 kVRMS Current Range (RoHS) Compliant Package Surface Mount ±10A -000E SO-8 X ±20A ±30A -500E X -000E X -500E X -000E X -500E X Tape and Reel X X X 1 min. rating Quantity X 100 per tube X 1500 per reel X 100 per tube X 1500 per reel X 100 per tube X 1500 per reel To order, choose a part number from the part number column and combine with the desired option from the option column to form an order entry. Example: Select ACHS-7122-500E to order product of ±20A, surface-mount package in tape and reel packaging and RoHS compliance. Contact your Broadcom sales representative or authorized distributor for information. Option data sheets are available. Contact your Broadcom sales representative or authorized distributor for information. Broadcom ACHS-712x-DS103 3 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Package Outline Drawing ACHS-7121/7122/7123 SO-8 Package 1.27 (0.050) 0.457 (0.018) 8 7 6 5 Part Number XXXX YYWW EEE Datecode RoHS Compliance 7.49 (0.295) +0.254 3.937 –0.127 (0.155 +0.010 ) –0.005 Lot ID 1.9 (0.075) 1 2 3 4 0.64 (0.025) +0.254 5.080 –0.127 (0.200 +0.010 ) –0.005 7° 0.254 ±0.050 (0.010 ±0.002) 1.908 ±0.127 (0.075 ±0.005) 0.381±0.127 (0.015 ±0.005) 0.800 ±0.127 (0.031 ±0.005) 0.203 ±0.100 (0.008 ±0.004) 0° to 7° +0.254 6.000 –0.127 +0.010 (0.236 –0.005) Dimensions in millimeters (inches). NOTE: Lead coplanarity = 0.100 mm (0.004 in.) maximum. Floating lead protrusion = 0.254 mm (0.010 in.) maximum. Mold Flash on each side = 0.127 mm (0.005 in.) maximum. Recommended Pb-Free IR Profile Recommended reflow condition as per JEDEC Standard, J-STD-020 (latest revision). Non-halide flux should be used. Broadcom ACHS-712x-DS103 4 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Regulatory Information The ACHS-7121/7122/7123 is approved by the following organizations: UL/cUL UL 1577, component recognition program up to VISO = 3000VRMS. Approved under CSA Component Acceptance Notice #5. Insulation and Safety Related Specifications Parameter Symbol Value Units Minimum External Air Gap (External Clearance) L(101) 4.0 mm Measured from input terminals to output terminals, shortest distance through air. Minimum External Tracking (External Creepage) L(102) 4.0 mm Measured from input terminals to output terminals, shortest distance path along body. — 0.05 mm Through insulation distance, conductor to conductor, usually the direct distance between the primary input conductor and detector IC. CTI >175 V DIN IEC 112/VDE 0303 Part 1. — IIIa — Material Group (DIN VDE 0110, 1/89, Table 1). Minimum Internal Plastic Gap (Internal Clearance) Tracking Resistance (Comparative Tracking Index) Isolation Group Conditions Absolute Maximum Rating Parameter Symbol Min. Max. Units Storage Temperature TS –55 125 °C Ambient Operating Temperature TA –40 110 °C Junction Temperature TJ — 150 °C Primary Conductor Lead Temperature TL — 150 °C Supply Voltages VDD –0.5 8.0 V Output Voltage VOUT –0.5 VDD + 0.5 V IOUT(source) — 10 mA TA = 25°C IOUT(sink) — 10 mA TA = 25°C IP — 100 A PIN — 900 mW TA = 25°C POUT — 90 mW TA = 25°C Output Current Source Output Current Sink Overcurrent Transient Tolerance Input Power Dissipation Output Power Dissipation Broadcom Test Conditions Pins 1, 2, 3, or 4 1 pulse, 100 ms; TA = 25°C ACHS-712x-DS103 5 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Recommended Operating Conditions Parameter Symbol Min. Max. Units TA –40 110 °C VDD 4.5 5.5 V Output Capacitive Load CLOAD — 10 nF Output Resistive Load RLOAD 4.7 — kΩ IP –10 10 A ACHS-7122 –20 20 A ACHS-7123 –30 30 A Ambient Operating Temperature Supply Voltage Input Current Range ACHS-7121 Common Electrical Specifications Unless otherwise stated, all minimum/maximum specifications are over recommended operating conditions, CF = 1 nF. All typical values are based on TA = 25°C, VDD = 5.0V, CF = 1 nF. Parameter Symbol Min. Typ. Max. Units IDD — 13 15 mA RPRIMARY — 0.7 — mΩ Zero Current Output Voltage VOUT(Q) — VDD/2 — V Input Filter Resistance RF(INT) — 1.6 — kΩ Bandwidth BW — 80 — kHz Rise Time tr — 4 — μs 10 a tPO — 21 — μs 8 a CMTI 25 — — kV/us Supply Current Primary Conductor Resistance Power-on Time Common Mode Transient Immunity Test Condition VDD = 5V, output open Figure Note 5, 6 a a Bidirectional, IP = 0A 2 a a dB a VCM = 1000V b a. See Definition of Electrical Characteristics. b. Common Mode Transient Immunity is tested by applying a fast rising/falling voltage pulse across pin 4 and GND (pin 5). The output glitch observed is less than 0.2V from the average output voltage for less than 1 µs. Broadcom ACHS-712x-DS103 6 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Electrical Specifications ACHS-7121 Unless otherwise stated, all minimum/maximum specifications are over recommended operating conditions, CF = 1 nF. All typical values are based on TA = 25°C, VDD = 5.0V, CF = 1 nF. Parameter Symbol Min. Typ. Max. Units Figure Note IP –10 — 10 A 7 a Sensitivity Sens — 185 — mV/A –10A ≤ IP ≤ 10A 1 b Sensitivity Error ESENS –3 — 3 % TA = 25°C, VDD = 5V 1 b Sensitivity Slope ΔSens — 0.04 — mV/A/°C TA = –40°C to 25°C 1 b Sensitivity Slope ΔSens — 0.01 — mV/A/°C TA = 25°C to 110°C 1 b VOE –30 — 30 mV TA = 25°C 2 b Zero Current Output Error Slope ΔVOE — 0.03 — mV/°C TA = –40°C to 25°C 2 b Zero Current Output Error Slope ΔVOE — 0.06 — mV/°C TA = 25°C to 110°C 2 b Output Noise VN(RMS) — 7.8 — mV BW = 2 kHz 9 c Nonlinearity NL — 0.27 — % 3 d ETOT — ±1.5 — % 4 e ESENS_DRIFT — ±2 — % b ETOT_DRIFT — ±2 — % b Optimized Input Current Range Zero Current Output Error Total Output Error Sensitivity Error Lifetime Drift Total Output Error Lifetime Drift Test Conditions a. The device may be operated at higher primary current levels, IP, provided that the Maximum Junction Temperature, TJ(MAX) is not exceeded. b. See Definition of Electrical Characteristics. c. Output Noise is the noise level of the ACHS-7121/7122/7123 expressed in root mean square (RMS) voltage. d. Nonlinearity is defined as half of the peak-to-peak output deviation from the best-fit line, expressed as a percentage of the full-scale output voltage. See Definition of Electrical Characteristics for the complete definition and formula. e. Total output error in percentage is the difference between the measured output voltage at maximum input current (IPMAX) and the ideal output voltage at IPMAX divided by the ideal output voltage at IPMAX. The Total Output Error typical value is based on total output error measured at the point of product release. Broadcom ACHS-712x-DS103 7 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet ACHS-7122 Unless otherwise stated, all minimum/maximum specifications are over recommended operating conditions, CF = 1 nF. All typical values are based on TA = 25°C, VDD = 5.0V, CF = 1 nF. Parameter Symbol Min. Typ. Max. Units Figure Note IP –20 — 20 A 7 a Sensitivity Sens — 100 — mV/A –20A ≤ IP ≤ 20A 1 b Sensitivity Error ESENS –3 — 3 % TA = 25°C, VDD = 5V 1 b Sensitivity Slope ΔSens — 0.01 — mV/A/°C TA = –40°C to 25°C 1 b Sensitivity Slope ΔSens — 0.01 — mV/A/°C TA = 25°C to 110°C 1 b VOE –25 — 25 mV TA = 25°C 2 b Zero Current Output Error Slope ΔVOE — –0.01 — mV/°C TA = –40°C to 25°C 2 b Zero Current Output Error Slope ΔVOE — 0.02 — mV/°C TA = 25°C to 110°C 2 b Output Noise VN(RMS) — 4.1 — mV BW = 2 kHz 9 c Nonlinearity NL — 0.18 — % 3 d ETOT — ±1.5 — % 4 e ESENS_DRIFT — ±2 — % b ETOT_DRIFT — ±2 — % b Optimized Input Current Range Zero Current Output Error Total Output Error Sensitivity Error Lifetime Drift Total Output Error Lifetime Drift Test Conditions a. The device may be operated at higher primary current levels, IP, provided that the Maximum Junction Temperature, TJ(MAX) is not exceeded. b. See Definition of Electrical Characteristics. c. Output Noise is the noise level of the ACHS-7121/7122/7123 expressed in root mean square (RMS) voltage. d. Nonlinearity is defined as half of the peak-to-peak output deviation from the best-fit line, expressed as a percentage of the full-scale output voltage. See Definition of Electrical Characteristics for the complete definition and formula. e. Total output error in percentage is the difference between the measured output voltage at maximum input current (IPMAX) and the ideal output voltage at IPMAX divided by the ideal output voltage at IPMAX. The Total Output Error typical value is based on total output error measured at the point of product release. Broadcom ACHS-712x-DS103 8 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet ACHS-7123 Unless otherwise stated, all minimum/maximum specifications are over recommended operating conditions, CF = 1 nF. All typical values are based on TA = 25°C, VDD = 5.0V, CF = 1 nF. Parameter Symbol Min. Typ. Max. Units Figure Note IP –30 — 30 A 7 a Sensitivity Sens — 66 — mV/A –30A ≤ IP ≤ 30A 1 b Sensitivity Error ESENS –3 — 3 % TA = 25°C, VDD = 5V 1 b Sensitivity Slope ΔSens — 0.01 — mV/A/°C TA = –40°C to 25°C 1 b Sensitivity Slope ΔSens — 0.01 — mV/A/°C TA = 25°C to 110°C 1 b VOE –20 — 20 mV TA = 25°C 2 b Zero Current Output Error Slope ΔVOE — 0.01 — mV/°C TA = –40°C to 25°C 2 b Zero Current Output Error Slope ΔVOE — 0.02 — mV/°C TA = 25°C to 110°C 2 b Output Noise VN(RMS) — 2.7 — mV BW = 2 kHz 9 c Nonlinearity NL — 0.11 — % 3 d ETOT — ±1.5 — % 4 e ESENS_DRIFT — ±2 — % b ETOT_DRIFT — ±2 — % b Optimized Input Current Range Zero Current Output Error Total Output Error Sensitivity Error Lifetime Drift Total Output Error Lifetime Drift Test Conditions a. The device may be operated at higher primary current levels, IP, provided that the Maximum Junction Temperature, TJ(MAX) is not exceeded. b. See Definition of Electrical Characteristics. c. Output Noise is the noise level of the ACHS-7121/7122/7123 expressed in root mean square (RMS) voltage. d. Nonlinearity is defined as half of the peak-to-peak output deviation from the best-fit line, expressed as a percentage of the full-scale output voltage. See Definition of Electrical Characteristics for the complete definition and formula. e. Total output error in percentage is the difference between the measured output voltage at maximum input current (IPMAX) and the ideal output voltage at IPMAX divided by the ideal output voltage at IPMAX. The Total Output Error typical value is based on total output error measured at the point of product release. Package Characteristics Parameter Symbol Min. Typ. Max. Input-Output Momentary Withstand Voltage VISO 3000 — — Resistance (Input-Output) RI-O — Capacitance (Input-Output) CI-O — Junction-to-Ambient Thermal Resistance (due to Primary Conductor) Rθ12 Junction-to-Ambient Thermal Resistance (due to IC) Rθ22 Units Test Condition Note VRMS RH < 50%, t = 1 min., TA = 25°C a, b, c — Ω VI-O = 500VDC c 1.3 — pF f = 1 MHz c — 55 — °C/W Based on the Broadcom evaluation board d — 27 — °C/W Based on the Broadcom evaluation board d 10 14 a. In accordance with UL 1577, each device is proof tested by applying an insulation test voltage ≥ 3600 VRMS for 1 second. b. Input-Output Momentary Withstand Voltage is a dielectric voltage rating that should not be interpreted as an input-output continuous voltage rating. c. This is a two-terminal measurement: pins 1 through 4 are shorted together and pins 5 through 8 are shorted together. d. The Broadcom evaluation board has 300 mm2 (total area including top and bottom copper) of 2 oz. copper connected to pins 1 and 2 and pins 3 and 4. Refer to the application section for additional information on thermal characterization. Broadcom ACHS-712x-DS103 9 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Typical Performance Plots All typical plots are based on TA = 25°C, VDD = 5V, CF = 1 nF, unless otherwise stated. Figure 1: Sensitivity vs. Temperature Figure 2: Zero Current Output Voltage vs. Temperature Zero Current Output Voltage (VOUT(Q)) – V Sensitivity (Sens) – mV/A 200 175 ACHS-7121 ACHS-7122 150 ACHS-7123 125 100 75 50 –40 –20 0 20 40 60 80 100 120 2.515 2.510 2.505 2.500 2.495 ACHS-7121 2.490 ACHS-7122 ACHS-7123 2.485 –40 –20 0 Temperature (TA) – °C Figure 3: Nonlinearity vs. Temperature 20 40 60 Temperature (TA) – °C 80 100 120 Figure 4: Total Output Error at IPMAX vs. Temperature 0.30 8.0% Total Output Error (ETOT) – % 0.28 0.26 Nonlinearity (NL) – % 0.24 0.22 0.20 0.18 0.16 0.14 0.12 0.10 0.08 ACHS-7121 0.06 4.0% 2.0% 0.0% –2.0% ACHS-7121 –4.0% ACHS-7122 –6.0% ACHS-7123 ACHS-7122 0.04 –8.0% –40 ACHS-7123 0.02 0.00 –40 6.0% –20 0 20 40 60 80 100 –20 0 20 40 60 Temperature (TA) – °C 80 100 120 120 Temperature (TA) – °C Broadcom ACHS-712x-DS103 10 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Figure 6: Supply Current vs. Supply Voltage 13.8 14.5 13.6 14.0 Supply Current (IDD) – mA Supply Current (IDD) – mA Figure 5: Supply Current vs. Temperature 13.4 13.2 13.0 12.8 13.5 13.0 12.5 110°C 12.0 25°C –40°C 11.5 12.6 –40 –20 0 20 40 60 80 100 120 11.0 Temperature (TA) – °C 3 3.5 4 4.5 5 5.5 Figure 7: Output Voltage vs. Input Current Figure 8: Power On Time vs. External Filter Capacitance 100 5.0 IP = IP(max) 4.0 Power On Time (tPO) – ȝs Output Voltage (VOUT) – V 4.5 3.5 3.0 2.5 2.0 ACHS-7121 1.5 ACHS-7122 1.0 80 60 40 20 ACHS-7123 0.5 0.0 –30 0 –20 –10 0 10 20 30 0 Figure 9: Output Noise vs. External Filter Capacitance 2 4 6 8 10 External Filter Capacitance (CF) – nF Input Current (IP) – A Figure 10: Rise Time vs. External Filter Capacitance 30 10 25 Rise Time (tR) – ȝs Output Noise (VN(RMS)) – mV 6 Supply Voltage (VDD) – V 1 ACHS-7121 ACHS-7122 20 15 10 5 ACHS-7123 0.1 0.01 Broadcom IP = IP(max) 0 0.1 1 10 External Filter Capacitance (CF) – nF 100 0 2 4 6 8 10 External Filter Capacitance (CF) – nF ACHS-712x-DS103 11 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet Definition of Electrical Characteristics The ACHS-7121/7122/7123 product series is a Hall Effect current sensor that outputs an analog voltage proportional to the magnetic field intensity caused by the current flowing through the input primary conductor. Without the magnetic field, the output voltage is half of the supply voltage. The sensor can detect both DC and AC current. Figure 11: Nonlinearity Calculation VOUT Max¨ from BFL Min¨ from BFL Ratiometric Output IP(MIN) The output voltage of the ACHS-7121/7122/7123 series is ratiometric or proportional to the supply voltage. The sensitivity (Sens) of the device and the quiescent output voltage changes when there is a change in the supply voltage (VDD). For example, when the VDD is increased by 10% from 5V to 5.5V in the ACHS-7122, the quiescent output voltage changes from 2.5V to 2.75V and the sensitivity also changes from 100 mV/A to 110 mV/A. The output sensitivity (Sens) is the ratio of the output voltage (VOUT) over the input current (IP) flowing through the primary conductor. It is expressed in mV/A. When an applied current flows through the input primary conductor, it generates a magnetic field which the Hall IC converts into a voltage. The proportional voltage is provided by the Hall IC which is programmed in the factory for accuracy after packaging. The output voltage has a positive slope when an increasing current flows through pins 1 and 2 to pins 3 and 4. Sensitivity Error (ESENS) is the difference between the measured Sensitivity and the Ideal Sensitivity expressed as a percentage (%). Nonlinearity Nonlinearity is defined as half of the peak-to-peak output deviation from the best-fit line (BFL), expressed as a percentage of the full-scale output voltage. The full-scale output voltage is the product of the sensitivity (Sens) and full scale input current (IP). [(Max¨ from BFL – Min¨ from BFL) / 2] Sens X full scale I P Broadcom IP(MAX) BFL Zero Current Output Voltage Sensitivity NL(%) = full scale IP) This is the output voltage of ACHS-7121/7122/7123 when the primary current is zero. Zero current output voltage is half of the supply voltage (VDD/2). Zero Current Output Error This the voltage difference between the measured output voltage and the ideal output voltage (VDD/2) when there is no input current to the device. Total Output Error Total output error in percentage is the difference between the measured output voltage at maximum input current (IPMAX) and the ideal output voltage at IPMAX divided by the ideal output voltage at IPMAX. E TOT (%) = Measured VOUT @ I PMAX – Ideal V OUT @ I PMAX × 100% Ideal VOUT @ I PMAX Power-On Time × 100% This is the time required for the internal circuitry of the device to be ready during the ramping of the supply voltage. Power on time is defined as the finite time required for the output voltage to settle after the supply voltage reached its recommended operating voltage. ACHS-712x-DS103 12 ACHS-7121/7122/7123 Data Sheet FILTER Pin Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor Figure 12: Land Pattern for 4 mm Creepage The ACHS-7121/7122/7123 has a FILTER pin for improving the signal-to-noise ratio of the device. This eliminates the need for an external RC filter for the VOUT pin of the device, which can cause attenuation of the output signal. A ceramic capacitor, CF, can be connected between the FILTER pin to GND. 7.1 (0.280) Application Information 1.50 (0.059) PCB Layout The design of the printed circuit board (PCB) should follow good layout practices, such as keeping bypass capacitors close to the supply pin and use of ground and power planes. A bypass capacitor must be connected between pins 5 and 8 of the device. The layout of the PCB can also affect the common-mode transient immunity of the device due to stray capacitive coupling between the input and output circuits. To obtain maximum common-mode transient immunity performance, the layout of the PCB should minimize any stray coupling by maintaining the maximum possible distance between the input and output sides of the circuit and ensuring that any ground or power plane on the PCB does not pass directly below or extend much wider than the body of the device. 0.64(0.025) Effect of PCB Layout on Sensitivity The trace layout on the input pins of ACHS-7121/7122/7123 affects the sensitivity. It is recommended that the PCB trace connection to the input pins covers the pins fully, as shown in Figure 13. Figure 13: Recommended Trace Layout on Input Pins PCB TRACE IP- IP+ PCB TRACE Land Pattern for 4 mm Board Creepage For applications that require PCB creepage of 4 mm between input and output sides, the land pattern in Figure 12 can be used. Broadcom ACHS-712x-DS103 13 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 3 kVRMS Isolation and Low-Resistance Current Conductor ACHS-7121/7122/7123 Data Sheet When the connection to the input pin only covers the vertical portion of the input pin, there is a sensitivity variation of about –0.6% versus recommended PCB trace layout (as shown in Figure 14). Figure 14: Vertical Portion Connection PCB TRACE IP- PCB TRACE IP+ Thermal Consideration The evaluation board used in the thermal characterization is shown in Figure 16. Inputs IP+ and IP– are each connected to input plane of 2 oz. copper with 300 mm2 total area (including top and bottom planes). The output side GND is connected to a ground plane of 2 oz. copper with 460 mm2 total area (including top and bottom planes). The 2 oz. copper enables the board to conduct higher current and achieve good thermal distribution in a limited space. Figure 16: Broadcom Evaluation Board – Top Layer When the connection to the input pin only covers the horizontal portion of the input pin, there is a sensitivity variation of about +1.2% versus recommended PCB trace layout (as shown in Figure 15). Figure 15: Horizontal Portion Connection PCB TRACE IP- IP+ PCB TRACE Figure 17: Broadcom Evaluation Board – Bottom Layer Broadcom ACHS-712x-DS103 14 Broadcom, the pulse logo, Connecting everything, Avago Technologies, Avago, and the A logo are among the trademarks of Broadcom and/or its affiliates in the United States, certain other countries and/or the EU. Copyright © 2018–2020 by Broadcom. All Rights Reserved. The term “Broadcom” refers to Broadcom Limited and/or its subsidiaries. For more information, please visit www.broadcom.com. Broadcom reserves the right to make changes without further notice to any products or data herein to improve reliability, function, or design. Information furnished by Broadcom is believed to be accurate and reliable. However, Broadcom does not assume any liability arising out of the application or use of this information, nor the application or use of any product or circuit described herein, neither does it convey any license under its patent rights nor the rights of others.