CT220BMC-HS5

CT220 ALLEGRO

Document overview

• Manufacturer or author: Provided By www.digicamel.com(free datasheet download site)
• PDF pages: 25

Technical content

The CT220 is a high-linearity and high-resolution contactless current sensor from Allegro developed on its patented XtremeSense™ TMR technology. The CT220 measures the magnetic field of the current flowing through a busbar or printed circuit board (PCB) trace and converts it to an analog output voltage that represents the field and therefore current. As a contactless current sensor, it has an inherently high isolation, making it an ideal solution for applications where product safety compliance is a requirement due to high operating voltages combined with human interaction with the product. The CT220 achieves XtremeSense performance with a typical total output error of ±0.5% while sensing field (current) as low as 5 mA. The device supports a wide operating voltage range of 2.7 to 5.5 V . The CT220 is an ideal contactless current sensing solution for applications that must have excellent isolation and accurate current measurements. There are four variants of the CT220 that will sense the following magnetic fields: ±1.5 mT, ±5.0 mT, ±10.0 mT, and ±15.0 mT. The device also integrates a FLAG output that is active low and indicates when the field is above 90% and below 10% the full field range. The CT220 is available in an industry standard 5-lead SOT23 package. CT220-DS, Rev. 1 MCO-0001516

• AC or DC contactless current sensing
• Inherently high isolation
• Magnetic field (current) range: □ ±1.5 mT □ ±5.0 mT □ ±10.0 mT □ ±15.0 mT
• Stable performance over temperature
• Supply current: ~1.2 mA
• FLAG Pin to indicate 90% and 10% of full field range □ Active low digital output (push-pull)
• Supply voltage: 2.7 to 5.5 V
• Operating temperature ranges: □ Industrial: –40°C to 85°C □ Extended industrial: –40°C to 125°C
• Package: 5-lead SOT23 XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form Factor PACKAGE: Not to scale CT220 FEATURES AND BENEFITS DESCRIPTION December 15, 2023
• Contactless current sensing measurements
• Motor control
• Solar inverters
• Power distribution units (PDUS)
• UPS, SMPS, and telecom power supplies
• Smart appliances
• IoT smart plugs/energy devices
• Battery management systems
• Battery chargers
• PC and servers

APPLICATIONS

Figure 1: CT220 with Analog and FLAG Outputs in XtremeSense TMR State Machine Analog Front-End Digital (Push-pull) Analog

4 ANA

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems

955 Perimeter Road

Manchester, NH 03103-3353 U.S.A. www.allegromicro.com SELECTION GUIDE Part Number Magnetic Field Range (BANA) Sensitivity (mV/mT) VDD = 5 V Sensitivity (mV/mT) VDD = 3.3 V Total Error (%FS) Operating Temperature Range (°C) CT220BMC-IS5 ±1.5 mT (±15 G) 1500 990 ±3.0 –40 to 85 CT220BMC-HS5 –40 to 125 CT220BMV-IS5 ±5.0 –40 to 85 CT220BMV-HS5 –40 to 125 CT220FMC-IS5 ±5.0 mT (±50 G) 450 297 ±3.0 –40 to 85 CT220FMC-HS5 –40 to 125 CT220FMV-IS5 ±5.0 –40 to 85 CT220FMV-HS5 –40 to 125 CT220PMC-IS5 ±10.0 mT (±100 G) 225 148.5 ±3.0 –40 to 85 CT220PMC-HS5 –40 to 125 CT220PMV-IS5 ±5.0 –40 to 85 CT220PMV-HS5 –40 to 125 CT220RMC-IS5 ±15.0 mT (±150 G) 150 99 ±3.0 –40 to 85 CT220RMC-HS5 –40 to 125 CT220RMV-IS5 ±5.0 –40 to 85 CT220RMV-HS5 –40 to 125 EVALUATION BOARD ORDERING INFORMATION Part Number Current Range (mT) Total Error (%FS) Operating Temperature Range (°C) EVB222-1.5A ±1.5 ±3.0 –40 to 125 EVB222-5.0A ±5.0 EVB222-10A ±10.0 EVB222-15A ±15.0 Table of Contents

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com ABSOLUTE MAXIMUM RATINGS [1] Characteristic Symbol Notes Rating Unit Supply Voltage Strength VDD –0.3 to 6.0 V Push-Pull Output (Active LOW) VFLAG#_PP –0.3 to VDD + 0.3 [2] V Input/Output Pins Maximum Voltage VI/O –0.3 to VDD + 0.3 [2] V Electrostatic Discharge Protection Level ESD Human Body Model (HBM) per JESD22-A114 ±2.0 kV Junction Temperature TJ –40 to 150 °C Storage Temperature TSTG –65 to 150 °C Lead Soldering Temperature TL 10 seconds 260 °C [1] Stresses exceeding the absolute maximum ratings may damage the CT220 and may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. [2] The lower of VDD + 0.3 V or 6.0 V. RECOMMENDED OPERATING CONDITIONS [1] Characteristic Symbol Notes Min. Typ. Max. Unit Supply Voltage Range VDD 2.7 5.0 5.5 V Output Voltage Range VOUT 0 – VDD V Output Current IOUT – – ±10.0 µA Operating Ambient Temperature TA Industrial –40 25 85 °C Extended Industrial –40 25 125 °C [1] The Recommended Operating Conditions table defines the conditions for actual operation of the CT220. Recommended operating conditions are specified to ensure optimal performance to the specifications. Allegro does not recommend exceeding them or designing to absolute maximum ratings.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Terminal List Number Name Function 1 FLAG Outputs an active LOW flag signal to indicate when the current is above 90% or below 10% of the full current range. It is a push-pull output.

2 VDD Supply Voltage

3 GND Ground

4 ANA Analog output voltage that represents the measured current.

5 NC No Connect

PINOUT DIAGRAM AND TERMINAL LIST Figure 2: 5-Lead SOT23 Package, Top View N/C ANA VDDGNDFLAG 32 1 Figure 3: CT220: Axis of Sensitivity for Bipolar Magnetic Field with SOT23-5 Figure 4: CT220: Recommended Axis of Sensitivity for Unipolar Magnetic Field with SOT23-5

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com ELECTRICAL CHARACTERISTICS: Valid for VDD = 2.7 to 5.5 V, CBYP = 1.0 µF, and TA = –40°C to 125°C, typical values are VDD = 5.0 V and TA = 25°C, unless otherwise specified Characteristics Symbol Test Conditions Min. Typ. Max. Unit Average Supply Current IDD(AVG) t ≥ 10 seconds – 1.2 2.5 mA Sampling Frequency fS 150 200 250 kHz Idle Mode Time tIDLE 4.0 5.0 6.7 µs ANALOG OUTPUT (ANA) Maximum Drive Capability IDRV(MAX) ΔVOUT ≤ 150 mV, VDD ≥ 3.3 V –10 – 10 µA Analog Output Voltage Range VANA 0.05 × VDD – 0.95 × VDD V Voltage Output Quiescent VOQ 48.5 50.0 51.5 % VDD Rise Time [1] tRISE BANA = BANA(MAX), tVANA_90% – tVANA_10% – 15.5 – µs Propagation Delay [1] tDELAY BANA = BANA(MAX), tBANA – tVANA @ 20% of output value – 4.6 – µs Response Time [1] tRESP BANA = BANA(MAX), tBANA – tVANA @ 90% of output value – 20.0 – µs Input Referred Noise Density [1] eND fBW = 10 Hz, VDD = 5.0 V – 0.15 – µTRMS / √Hz Output Capacitive Load CL – – 10 pF FLAG PUSH-PULL OUTPUT ( FLAG) FLAG Voltage LOW VFLAG#_OL Unipolar and bipolar fields – 0.9 × VDD – V Bipolar field – 0.1 × VDD – V FLAG Voltage HIGH VFLAG#_OH Unipolar and bipolar fields – 0.86 × VDD – V Bipolar field – 0.14 × VDD – V Current for FLAG IFLAG# – ±2 – mA TIMINGS Power-On Time tON VDD ≥ 2.7 V – 50 75 µs Active Mode Time tACTIVE – 2.5 – µs PROTECTION Undervoltage Lockout VUVLO Rising VDD – 2.3 2.5 V Falling VDD 2.0 2.2 – V UVLO Hysteresis VUV_HYS – 100 – mV [1] Guaranteed by design and characterization; not tested in production.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com TYPICAL TIMING AND ELECTRICAL CHARACTERISTICS VDD = 5.0 V, TA = 25°C, and CBYP = 1.0 µF (unless otherwise specified) Figure 5: Power-On Time for CT220 Figure 6: Rise Time for CT220 Figure 7: Propagation Delay Time for CT220 Figure 8: Response Time for CT220 Figure 9: CT220 Average Supply Current vs. Temperature vs. Supply Voltage

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com CT220BMx (±1.5 mT) ELECTRICAL CHARACTERISTICS: Valid for VDD = 2.7 to 5.5 V, CBYP = 1.0 µF, and TA = –40°C to 125°C, typical values are VDD = 5.0 V and TA = 25°C, unless otherwise specified Characteristics Symbol Test Conditions Min. Typ. Max. Unit ANALOG OUTPUT Gain G VDD = 5.0 V, TA = 25°C 1475 1500 1525 mV/mT VDD = 3.3 V, TA = 25°C 973.5 990 1006.5 mV/mT Operating Magnetic Field BANA –1.5 – +1.5 mT RESOLUTION Resolution RES IBUSBAR = ±3.5 A [1] – 5.0 – mA TOTAL OUTPUT ERROR PERFORMANCE Total Output Error for CT220BMC [2] ETOT_BMC Total Output Error for CT220BMV [2] ETOT_BMV TOTAL OUTPUT ERROR COMPONENTS Non-Linearity Error eLIN BANA = ±1.5 mT, TA = –40°C to +125°C – ±0.15 – % FS Temperature Coefficient of Sensitivity for CT220BMC [3] TCSBMC TA = 0°C to 125°C – –70 – ppm/°C TA = –40°C to 125°C – –150 –250 ppm/°C Temperature Coefficient of Sensitivity for CT220BMV [3] TCSBMV TA = 0°C to 125°C – –100 – ppm/°C TA = –40°C to 125°C – –200 –400 ppm/°C Temperature Coefficient of Offset Voltage [3] TCO TA = –40°C to 125°C, VDD = 5.0 V – 100 – ppm/°C NOISE Input Referred Noise [1] eN fBW = 1 Hz to 30 kHz, VDD = 5.0 V – 1.76 – µTRMS – 2.64 – mVRMS [1] Measurement result from EVB222 (top trace on PCB), CT220 evaluation board. [2] Reference section CT220 Calibration Guide. [3] Guaranteed by design and characterization; not tested in production.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com TYPICAL ELECTRICAL AND MAGNETIC CHARACTERISTICS FOR CT220BM x VDD = 5.0 V, TA = 25°C, and CBYP = 1.0 µF (unless otherwise specified) Figure 10: CT220BMx Output Voltage vs. Magnetic Field vs. Temperature

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com CT220FMx (±5.0 mT) ELECTRICAL CHARACTERISTICS: Valid for VDD = 2.7 to 5.5 V, CBYP = 1.0 µF, and TA = –40°C to 125°C, typical values are VDD = 5.0 V and TA = 25°C, unless otherwise specified Characteristics Symbol Test Conditions Min. Typ. Max. Unit ANALOG OUTPUT Gain G VDD = 5.0 V, TA = 25°C 435 450 465 mV/mT VDD = 3.3 V, TA = 25°C 287.1 297 306.9 mV/mT Operating Magnetic Field BANA –5 – +5 ADC RESOLUTION Resolution RES ITRACE = ±3.5A [1] – 5.0 – mA TOTAL OUTPUT ERROR PERFORMANCE Total Output Error for CT220FMC [2] ETOT_FMC Total Output Error for CT220FMV [2] ETOT_FMV TOTAL OUTPUT ERROR COMPONENTS Non-Linearity Error eLIN BANA = ±5.0 mT, TA = –40°C to +125°C – ±0.15 – % FS Temperature Coefficient of Sensitivity for CT220FMC [3] TCSFMC TA = 0°C to 125°C – –70 – ppm/°C TA = –40°C to 125°C – –150 –250 ppm/°C Temperature Coefficient of Sensitivity for CT220FMV [3] TCSFMV TA = 0°C to 125°C – –100 – ppm/°C TA = –40°C to 125°C – –200 –400 ppm/°C Temperature Coefficient of Offset Voltage [3] TCO TA = –40°C to 125°C, VDD = 5.0 V – 100 – ppm/°C NOISE Input Referred Noise [1] eN fBW = 1 Hz to 30 kHz, VDD = 5.0 V – 1.85 – µTRMS – 0.83 – mVRMS [1] Measurement result from EVB222 (top trace on PCB), CT220 evaluation board. [2] Reference section CT220 Calibration Guide. [3] Guaranteed by design and characterization; not tested in production.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com TYPICAL ELECTRICAL AND MAGNETIC CHARACTERISTICS FOR CT220FM x VDD = 5.0 V, TA = 25°C, and CBYP = 1.0 µF (unless otherwise specified) Figure 11: CT220FMx Output Voltage vs. Current vs. Temperature

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com CT220PMx (±10.0 mT) ELECTRICAL CHARACTERISTICS: Valid for VDD = 2.7 to 5.5 V, CBYP = 1.0 µF, and TA = –40°C to 125°C, typical values are VDD = 5.0 V and TA = 25°C, unless otherwise specified Characteristics Symbol Test Conditions Min. Typ. Max. Unit ANALOG OUTPUT Gain G VDD = 5.0 V, TA = 25°C 215 225 235 mV/mT VDD = 3.3 V, TA = 25°C 141.9 148.5 155.1 mV/mT Current Sensing Range BANA –10 – +10 ADC RESOLUTION Resolution RES ITRACE = ±3.5 APK [1] – 5 – mA TOTAL OUTPUT ERROR PERFORMANCE Total Output Error for CT220PMC [2] ETOT_PMC Total Output Error for CT220PMV [2] ETOT_PMV TOTAL OUTPUT ERROR COMPONENTS Non-Linearity eLIN BANA = ±10.0 mT, TA = –40°C to 125°C – ±0.20 – % FS Temperature Coefficient of Sensitivity for CT220PMC [3] TCSPMC TA = 0°C to 125°C – –70 – ppm/°C TA = –40°C to 125°C – –150 –250 ppm/°C Temperature Coefficient of Sensitivity for CT220PMV [3] TCSPMV TA = 0°C to 125°C – –100 – ppm/°C TA = –40°C to 125°C – –200 –400 ppm/°C Temperature Coefficient of Offset Voltage [3] TCO TA = –40°C to 125°C, VDD = 5.0 V – 100 – ppm/°C NOISE Input Referred Noise [3] eN fBW = 1 Hz to 30 kHz, VDD = 5.0 V – 2.37 – µTRMS – 0.53 – mVRMS [1] Measurement result from EVB222 (top trace on PCB), CT220 evaluation board. [2] Reference section CT220 Calibration Guide. [3] Guaranteed by design and characterization; not tested in production.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com TYPICAL ELECTRICAL CHARACTERISTICS FOR CT220PMx VDD = 5.0 V, TA = 25°C, and CBYP = 1.0 µF (unless otherwise specified) Figure 12: CT220PMx Output Voltage vs. Current vs. Temperature

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com CT220RMx (±15.0 mT) ELECTRICAL CHARACTERISTICS: Valid for VDD = 2.7 to 5.5 V, CBYP = 1.0 µF, and TA = –40°C to 125°C, typical values are VDD = 5.0 V and TA = 25°C, unless otherwise specified Characteristics Symbol Test Conditions Min. Typ. Max. Unit ANALOG OUTPUT Gain G VDD = 5.0 V, TA = 25°C 145 150 155 mV/mT VDD = 3.3 V, TA = 25°C 95.7 99 102.3 mV/mT Current Sensing Range BANA –15 – +15 ADC RESOLUTION Resolution RES ITRACE = 3.5 A [1] – 5.0 – mA TOTAL OUTPUT ERROR PERFORMANCE Total Output Error for CT220RMC [2] ETOT_PMC Total Output Error for CT220RMV [2] ETOT_PMV TOTAL OUTPUT ERROR COMPONENTS Non-Linearity eLIN BANA = ±15.0 mT, TA = –40°C to 125°C – ±0.30 – % FS Temperature Coefficient of Sensitivity for CT220RMC [3] TCSPMC TA = 0°C to 125°C – –70 – ppm/°C TA = –40°C to 125°C – –150 –250 ppm/°C Temperature Coefficient of Sensitivity for CT220RMV [3] TCSPMV TA = 0°C to 125°C – –100 – ppm/°C TA = –40°C to 125°C – –200 –400 ppm/°C Temperature Coefficient of Offset Voltage [3] TCO TA = –40°C to 125°C, VDD = 5.0 V – 100 – ppm/°C NOISE Input Referred Noise [3] eN fBW = 1 Hz to 30 kHz, VDD = 5.0 V – 2.38 – µTRMS – 0.36 – mVRMS [1] Measurement result from EVB222 (top trace on PCB), CT220 evaluation board. [2] Reference section CT220 Calibration Guide. [3] Guaranteed by design and characterization; not tested in production.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com TYPICAL ELECTRICAL CHARACTERISTICS FOR CT220RMx VDD = 5.0 V, TA = 25°C, and CBYP = 1.0 µF (unless otherwise specified) Figure 13: CT220RMx Output Voltage vs. Current vs. Temperature

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com FUNCTIONAL DESCRIPTION Overview The CT220 is a high-resolution and low-noise contact current sensor with isolation and a FLAG output that operates from 2.7 to 5.5 V assembled in an industry standard 5-lead SOT23 package. The chip measures the magnetic field of the current through the package and converts it to an analog signal that is equivalent to the current flowing through the printed circuit board (PCB) trace. The FLAG output indicates whether there is an overcurrent condition seen by CT220 during operation and will alert the host system. Analog Output Measurement The CT220 provides a continuous (sample and hold) linear ana- log output voltage which represents the measured magnetic field of the current. The output voltage range of ANA is 5.0% to 95.0% of VDD which represents the current from the typical low-end val- ues (–5.0 to –15.0 APK) to the maximum current values (+5.0 to +15.0 mT) respectively. The output sample frequency is 200 kHz. A resistor-capacitor (R-C) filter may be implemented on the ANA pin to further lower the noise. Figure 14 illustrates the output voltage range of the ANA pin as a function of the measured cur- rent for ±5.0 A (–1.5 to –15.0 mT) to the maximum field values (+1.5 to +15.0 mT) respectively. The output sampling frequency is 200 kHz. A resistor-capacitor (R-C) filter may be implemented on the ANA pin to further lower the noise. Figure 14 illustrates the output voltage range of the ANA pin as a function of the measured field of ±1.5 mT while Figure 15 shows the VANA vs. measured field of ±15.0 mT. VANA 95.0% VDD 50.0% VDD 5.0% VDD -1.5 mT 0 mT +1.5 mT BANA Figure 14: Linear Output Voltage Range vs. Measured Cur- rent for G = 300 mV/V/mT and current range of +1.5 mT. VANA 95.0% VDD 50.0% VDD 5.0% VDD -15.0 mT 0 mT +15.0 mT BANA Figure 15: Linear Output Voltage Range vs. Measured Cur- rent for G = 30 mV/V/mT and current range of +15.0 mT. Current Detection Flag The Current Detection circuitry detects when the current mea- sured through the current-carrying conductor is above 90% or below 10% of the full current range. As a result, it translates to greater than 90% of VDD and 10% of VDD on the ANA pin. This will generate a flag signal via the FLAG pin to the host system microcontroller as an active LOW signal. Once VANA falls below 86% or rises above 14% of VDD, then the FLAG signal will go high. Rise Time (tRISE) The CT220 rise time, tRISE, is the time interval of when it reaches 10% and 90% of the full-scale output voltage. The tRISE of the CT220 is 15.5 µs. Propagation Delay (tDELAY) The propagation delay, tDELAY, is the time measured between ICCC reaching 20% of its final value and the CT220 attaining 20% of its full-scale output voltage. Its propagation delay is 4.6 µs.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com 90% BANA VANA 20% 10% tDELAY t tRISE Figure 16:CT220 Propagation Delay and Rise Time Curve Response Time (tRESP) The response time, tRESP, is the difference in time from when ICCC reaches 90% of its final value and VANA attains 90% of its final value. The CT220 response time is typically 20.0 µs. t VANA 90% ICCC tRESP Figure 17: CT220 Response Time Curve Power-On Time (tON) The Power-On Time (tON) of 50 µs is the amount of time required by the CT220 to start up, power-on, and acquire the first sample. The chip is fully powered up and operational from the moment the supply voltage passes the rising UVLO point (2.3 V). This time includes ramp-up time and settling time (within 10% of steady-state voltage when current is flowing through the package) after the power supply has reached the minimum VDD. Start-up Phase Steady-state Operation VDD ANA IDD 50 µs T < 1 ms* 100 nA (AVG) 1.6 mA (MAX) VUVLO Timing, voltage and current levels are not to scale. *The maximum average supply current of 1.6 mA is time averaged over a 1 ms period. Figure 18: CT220 Power-On Timing Diagram Undervoltage Lockout (UVLO) The Undervoltage Lockout protection circuitry of the CT220 is activated when the supply voltage (VDD) falls below 2.1 V . The CT220 remains in a low quiescent state and the ANA output is not valid until VDD rises above the UVLO threshold (2.3 V). Low Resolution and Low Noise For the unipolar field, the resolution is TBD µT (5 mA) while the input referred noise in TBD µTRMS (7 mARMS) however there is no contradiction in the CT220’s capability to sense this level of current because the 5 mA was measured with a digital multi- meter (DMM) with limited bandwidth whereas the noise is over a wider bandwidth (up to 30 kHz).

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Introduction All current sensors, no matter how expensive they are, or what materials they use, or even if they were factory-calibrated, are susceptible to deviations from their Ideal Transfer Line. To extract the absolute best performance from any current sens- ing system, calibration is required. Ideal Transfer Line Ideally, the sensor output follows a straight line, has a fixed slope, and crosses a fix offset point. This allows the user to apply a straightforward linear equation to extract the physical value being measured. In the case of a current sensor: = − where a is the slope and b is the offset of the ideal curve. In a perfect sensor, both a and b coefficients can be simply looked up on the datasheet. Figure 19: Ideal Transfer Line Any deviations from this Ideal Line are considered sensor errors—more specifically, Accuracy Errors as they related in the case of Allegro sensors to Gain and Offset errors. Offset Error Based on the Ideal Transfer Line, when no current is applied, the voltage output of the sensor should be equal to 50% of VDD. Figure 20: Exaggerated Offset Error Gain Error The Ideal Transfer Line shows a line that reaches 95% of VDD at the maximum operating current and 5% of VDD at the minimum. Figure 21: Exaggerated Gain Error Calibration Different methods can be applied for offset and/or gain correc- tion. The complexity of these methods lead to different calibration results. The higher the complexity the better the error correction. CALIBRATION GUIDE

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Simple Offset Correction Offset calibration is achieved simply by storing the voltage out- put of the sensor at zero flowing current. Figure 22: Simple Offset Calibration This stored value VOFFSET becomes the coefficient b in the linear transfer function: = − Simple Gain Correction Basic Gain calibration can be achieved by applying a known current value (A1) and measuring the sensor output voltage value (V1). Figure 23: Simple Gain Calibration The following equation is used to calculate the slope coefficient a: = 1 − Recommended Offset and Gain Correction For bidirectional current applications, the steps below are recom- mended for users trying to perform the best error correction of gain and offset. 1. Apply a known current value (A1) and measure voltage output (V1) 2. Apply a second current value (A2) and measure the voltage output (V2) 3. Calculate the slope using the following equation It is recommended that the applied currents A1 and A2 are the absolute maximum and minimum operating current the sensor will see during its normal operations. Also, A1 = –A2 for bidirectional current sensing. = 1 − 2 1 − 2 = 1 + 2 Figure 24: Gain Calibration Both calculated coefficients a and b are then used to calculate the current: = −

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com APPLICATIONS INFORMATION The CT220 is an ideal solution to measure current non-intrusively as it provides highly accurate current values by measuring the magnetic field that is generated by the flow of current through a PCB trace or busbar. Because this implementation is contactless, the isolation is infinite so there is no need to use isolation amplifiers. The CT220 only needs a 1.0 µF bypass capacitor connected to the VDD pin. A resistor-capacitor filter on the ANA pin is recommended to minimize the output noise as shown in Figure 24. Please refer to Table 2 for recommended cut-off frequencies. Figure 25: CT220 with Analog and FLAG Outputs Application Block Diagram Table 1: Recommended External Components for CT220 Component Description Vendor and Part Number Parameter Min. Typ. Max. Unit CBYP 1.0 µF, X5R or Better Murata GRM155C81A105KA12 C – 1.0 – µF RFILTER 50 kΩ, ±5% Various R – 50 – kΩ CFILTER 100 pF, X5R or Better Various C – 10 – pF Table 2: Recommended Cut-off Frequencies for CT220 and its Resistor-Capacitor Values Cut-off Frequency (kHz) Resistor Value (kΩ) Capacitor Value (pF) 1 105 1,500 10 105 150 30 50 100 XtremeSense TMR State Machine Analog Front-End Digital (Push-pull) Analog 1.0 μF 50 kΘ 100 pF Overview

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com The CT220 must be placed in the correct orientation on the PCB to measure unipolar current in either a PCB trace or a busbar above or beneath the device. The axis of sensitivity of the CT220 for unipolar magnetic fields, i.e. unipolar current is along the vertical direc- tion of the surface of the package pointing towards pin 1; see Figure 4 for reference. For unipolar measurements of either a top or bottom PCB trace and a busbar below the CT220, the flow of unipolar current is from left to right as shown in Figure 25. This direction is derived using Ampere’s right-hand rule where the thumb represents the direction of the current and the curl of the fingers is the direction of the magnetic field. In the case of an application using a busbar that is placed above the CT220 the current flows right to left, see Figure 26. Unipolar Current Measurement (A) (B) (A) (B) Figure 26: CT220 measuring unipolar current in a bus- bar below it where (A) indicates the unipolar current and magnetic field directions, and (B) is the direction of unipolar current flow that the CT220 must be ori- ented. Figure 27: Measuring unipolar current of a busbar placed above the CT220 where (A) shows the direction of the unipolar current and magnetic field, and (B) is the direction of unipolar current flow with respect to the CT220 package.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com TMR Sensor Location The x, y dimensions of CT220’s XtremeSense TMR sensor location in a 5-lead SOT23 are shown in Figure 27 while Figure 28 illus- trates the z dimension. All dimensions in the figures below are nominal and in millimeters (mm). Figure 28: XtremeSense TMR Sensor Location in X and Y Dimensions for CT220 in SOT23-5 Package Figure 29: XtremeSense TMR Sensor Location in Z Dimension for CT220 in SOT23-5 Package

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com PACKAGE OUTLINE DRAWING Figure 30: SOT23-5 Package Drawing and Dimensions NOTES: 1. Dimension e represents the basic terminal pitch. It specifies the geometric position of the terminal axis. 2. Dimension b applies to the metalized terminal pads. 3. Dimension A includes package warpage. 4. Exposed metalized pads are Cu (Copper) pads with OSP surface. 5. All dimensions are in millimeters (mm). Table 3: CT220 SOT23-5 Package Dimensions Symbol Dimensions in Millimeters (mm) Min. Typ. Max. A 1.05 1.20 1.35 A1 0.00 0.10 0.15 A2 1.00 – 1.20 b 0.40 – 0.50 b1 0.40 0.40 0.45 c 0.08 – 0.22 c1 0.08 0.13 0.20 D 2.80 2.90 3.00 E 2.60 2.80 3.00 E1 1.50 1.60 1.70 Symbol Dimensions in Millimeters (mm) Min. Typ. Max. e 0.95 BSC e1 1.90 BSC L 0.35 0.43 0.60 L1 0.60 REF L2 0.25 BSC R 0.10 – – R1 0.10 – 0.25 0 0° 4° 8° 01 5° 6° 15° 02 5° 8° 15°

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com NOTES: 1. Material: Conductive Polystyrene 2. Dimensions in mm. 3. 10 sprocket hole pitch cumulative tolerance ±0.20 mm. 4. Camber bot to exceed 1 mm in 100 mm. 5. Pocket position relative to sprocket hole measured as true position of pocket and not pocket hole. 6. (S.R. 0/sq) means surface electric resistivity of the carrier tape. Figure 31: Tape and Pocket Drawing for SOT23 Package TAPE AND REEL POCKET DRAWING AND DIMENSIONS

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com

PACKAGE INFORMATION

Table 4: CT220 Package Information Part Number Package Type # of Leads Package Quantity Lead Finish Eco Plan [1] MSL Rating [2] Operating Temperature [3] Device Marking [4] CT220BMC-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C ABY WWS CT220BMC-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C ABY WWS CT220BMV-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C ACY WWS CT220BMV-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C ACY WWS CT220FMC-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C AFY WWS CT220FMC-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C AFY WWS CT220FMV-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C AGY WWS CT220FMV-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C AGY WWS CT220PMC-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C APY WWS CT220PMC-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C APY WWS CT220PMV-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C AQY WWS CT220PMV-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C AQY WWS CT220RMC-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C ARY WWS CT220RMC-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C ARY WWS CT220RMV-IS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 85°C ASY WWS CT220RMV-HS5 SOT23 5 3000 Sn Green & RoHS 1 –40°C to 125°C ASY WWS [1] RoHS is defined as semiconductor products that are compliant to the current EU RoHS requirements. It also will meet the requirement that RoHS substances do not exceed 0.1% by weight in homogeneous materials. Green is defined as the content of chlorine (Cl), bromine (Br), and antimony trioxide based flame retardants satisfy JS709B low halogen requirements of ≤ 1,000 ppm. [2] MSL Rating = Moisture Sensitivity Level Rating as defined by JEDEC standard classifications. [3] Package will withstand ambient temperature range of –40°C to 150°C and storage temperature range of –65°C to 160°C. [4] Device Marking for SOT23 is defined as XZ YWWS where XZ = part number and Y = Year, WW = work week, and S = sequential number.

XtremeSense™ High-Linearity, High-Resolution TMR Current Sensor with FLAG Output in Miniature Form FactorCT220 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com For the latest version of this document, visit our website: www.allegromicro.com

Revision History

1 December 15, 2023 Document rebranded and minor editorial updates

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