Current transducer FHS 40-P/SP600 I = 0 - 100 A PM Minisens Introduction The Minisens transducer is an ultra flat SMD open loop integrated circuit current transducer based on the Hall effect principle. It is suitable for the electronic measurement of currents: DC, AC, pulsed, mixed. It has no insertion loss and provides galvanic isolation between the primary circuit (high power) and the secondary circuit (sensor). It measures the magnetic field generated by the current flowing in a conductor such as a PCB track. The output voltage is proportional to that magnetic field. The IC is calibrated to minimize offset and temperature drifts. An integrated magnetic circuit gives an optimum transducer sensitivity. High isolation between the primary circuit and transducer electronics can be obtained with a double sided PCB. This datasheet is for a device programmed for maximum sensitivity: other options will be available. For example, the sensitivity range will be adjustable, and a choice of fixed or ratiometric (proportional to power supply voltage) sensitivity and reference voltage will be offered. Features Applications Programmable Hall effect transducer for current measurement applications up to 100 A 5 V power supply Standard S0IC 8 pin package Magnetic field measurement range 3.3 mT Sensitivity range up over to 200 mV/A Isolated current measurement. Advantages Low cost Battery supplied applications Motor control Power meter Uninterruptible Power Supplies (UPS) Switched Mode Power Supplies (SMPS) Overcurrent fault protection Threshold detection Garage door opener Window shutters Motors and fans Air conditioning White goods. Application domain Small size Excellent linearity No power loss in primary circuit Internal or external reference voltage may be used on the same pin Standby mode for reduced power consumption Industrial. Standard EN 50178. Additional output for fast detection with response time 3 s. Page 1/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Absolute maximum ratings (non operating) Parameter Symbol VC Supply voltage Electrostatic discharge Unit V kV Specifications Conditions 5.6 Exceeding this voltage may temporarily reconfigure the circuit until next power-on 8.25 Destructive 2 Latch-Up, Normal mode Human Body Model According to Jedec Standard JESD78A Latch-Up, Standby mode Latch-Up voltage in Standby mode According to Jedec Standard JESD78A @ 25C V 6.5 @ 125C Ambient operating temperature TA C - 40 .. + 125 Ambient storage temperature TS C - 55 .. + 150 Output short circuit duration Indefinite Block diagram This block diagram includes user programmable options: please contact LEM for details. VC Output stage VOUTFast VOUT Hall sensor array, concentrator and front end electronics Sensitivity sign change Output control Sensitivity, Drift, Offset 3.03 *Rref Programmer Standby Rref 200 Ohm Hall biasing and temperature comp. Bandgap Ref. 1.23V 0V 200 Ohm Ref calibration VRef Page 2/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Notes: All parameters are for the VC range from 4.5 V to 5.5 V, and TA = - 40C to + 125C. Typical values are for VC = 5 V; TA = 25C. Values are for the application schematic shown in figure 6. Electrical data Parameter Symbol VC Supply voltage IC Current consumption Output voltage in a flux density B Magnetic flux density measuring range Unit V Min Typ 4.75 mA Max Conditions 4.5 V possible but limits 5 5.5 15 19 Operating mode 20 Standby mode A VOUT V VREF + VOE + (G x B) BM mT 3.3 measurement range Simplified model VC = 5 V GB = 600 mV/mT, Linearity error L % -1.5 0.4 1.5 Sensitivity, referred to magnetic field GB mV/mT 582 600 618 % of VC = 5 V value -1 1 350 Refered to 25C; 3 sigma limits 2.52 @ 25C, VC = 5 V Sensitivity - VC influence Temperature coefficient of GB TCG ppm/C -350 Reference voltage (Internal reference used as output) VREF V 2.480 mV/V -5 150 Regulation VC Output impedance VREF 2.5 5 200 B = 3.3, VC = 5 V @ 25C, VC = 5 V @ 25C, @ VC = 5 V 10% @ 25C, VC = 5 V 10% 250 Temperature coefficient of VREF TCVREF ppm/C -80 80 25C - 125C; 3 sigma limits Temperature coefficient of VREF TCVREF ppm/C -100 100 -40C - 25C; 3 sigma limits VREF V 1.5 2.8 Reference voltage (External reference used as input) Additional sensitivity error %/V -1 1 Relative to 2.5 V mV/V -40 20 Relative to 2.5 V VOE mV -10 10 @ 25C, B = 0; VC = 5 V Electrical offset voltage VOUTFast - VREF VOEFast mV Temperature coefficient of VOE and VOEFast TCVOE mV/C -0.15 0.15 mV -10 10 @ 25C, VC = 5 V 10% 5 DC 10 DC Additional electrical offset voltage Electrical offset voltage VOUT - VREF Offset - VC influence (VOE and VOEFast) Output resistance VOUT ROUT Output resistance VOUTFast ROUTFast Output current magnitude VOUT IOUT Output current magnitude VOUTFast Maximum output capacitive loading mA IOUTFast mA CL nF Standby pin "0" level @ 25C, B = 0; VC = 5 V 50 Refered to 25C and VREF; 3 sigma limits 30 As source 50 As sink 5 As source 10 As sink 18 4.7 nF recommended V -0.3 Standby pin "1" level V VC-0.5 Time to switch from standby to normal mode s 60 90 % of correct output Vrms/Hz 15 f = 1500 Hz - 100 Hz (f = 500 kHz typ) Output voltage noise VOUT and VOUTFast Vno +0.5 VC+0.3 Internal Clock feed through VOUT Vrms 400 Internal Clock feed through VOUTFast Vrms 1600 For standby mode (f = 500 kHz typ) Reaction time VOUT tra s 3 Input signal rise time 1 s Response time VOUT tr s 5 Input signal rise time 1 s Reaction time VOUTFast traFast s 3 Input signal rise time 1 s Response time VOUTFast trFast s 3 Input signal rise time 1 s Frequency bandwidth VOUT Frequency bandwidth VOUTFast BW BWFast kHz kHz 105 @ -3 dB (Kit 9) 45 @ -1 dB (Kit 9) 120 @ -3 dB (Kit 9) 55 @ -1 dB (Kit 9) Page 3/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Typical performance charateristics Figure 1: Output voltage noise Typical Linearity error at +125C Typical Linearity error at +25C 0.6% 0.5% 0.4% 0.4% 0.3% 0.2% -3.5 0.0% -3 -2.5 -2 -1.5 -1 -0.5 0 -0.1% 0.5 1 1.5 2 2.5 3 3.5 Typical Linearity Error (% of full scale) Typical Linearity Error (% of full scale) 0.2% 0.1% -3.5 0.0% -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 -0.2% -0.2% -0.3% -0.4% -0.4% -0.5% B (mT) Figure 2: Typical linearity error at +25C -0.6% B (mT) Figure 3: Typical linearity error at +125C Page 4/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Typical performance charateristics 1 180 -1 Gain -2 Phase 90 -3 0 -4 -5 Phase () Gain (dB) 0 -90 Kit 9, V OUT -6 -7 -180 100 1000 10000 100000 1000000 Frequency (Hz) 1 180 0 90 -2 Gain -3 Phase 0 -4 -5 Phase () Gain (dB) -1 -90 Kit 9, V OUT Fast -6 -7 -180 100 1000 10000 100000 1000000 Frequency (Hz) Figure 4: Typical frequency and phase response; VOUT and VOUTFast Page 5/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Typical performance charateristics Figure 5: Best and worst case di/dt response - VOUT and VOUTFast Conditions: IP = 50 A - primary track on opposite side of PCB Page 6/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Typical connection diagram and ground plane Values of the electrical data given page 3 are according to the following connection diagram. isolation barrier +5V * 5, 6 0V IP C3 4 VC VOUT Primary conductor VOUTFast VREF STANDBY 7 2 * 8 1 * C2 VSFast VS C1 0V 3 VSTANDBY Figure 6: Typical connection diagram (C1 = C3 = 47 nF, C2 = 4.7 nF) Careful design of the PCB is needed to ensure minimum disturbance by surrounding currents and external fields. C1 to C3 should be mounted as close as possible to the pins. The maximum capacitor value allowed on VOUT is 18 nF. It is recommended to use 4.7 nF. The maximum capacitor value allowed on VOUTFast is 330 pF. A positive output voltage VS is obtained with a current (IP) flowing under Minisens from the pin 4/5 end of the package to the pin 1/8 end. VSFast is negative when VS is positive. If the pin VOUTFast is not used, it should be connected only to a small solder pad. Coupling to other tracks should be minimized. An internally generated reference voltage of 2.5 V with a source resistance of 200 W is available on the pin VREF. The voltage on this pin may be forced externally with a voltage in the range 1.5 - 2.8 V. The output voltage VS is limited to approximately the value of VREF in both positive and negative polarities. VSTANDBY should be connected to a low impedance so that capacitive coupling from adjacent tracks does not disturb it (there is an internal pull-down whose resistance is 500 kW). It should be connected to 0 V if not used. Connect VSTANDBY to the same voltage as VC to activate the Standby mode. VREF should not be forced in Standby mode. Minisens can be directly mounted above the PCB track in which the current to be measured flows (see kit 4, for example). Page 7/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Typical connection diagram and ground plane Good EMC practice requires the use of ground planes on PCBs. In drives where high dV/dt transients are present, a ground plane between the primary conductor and Minisens will reduce or avoid output perturbations due to capacitive currents. However, the ground plane has to be designed to limit eddy currents that would otherwise slow down the response time. The effect of eddy currents is made negligible by cutting the copper plane under the package as shown in figure 7: cut in the plane under the circuit Figure 7: Top side copper plane has a cut under the IC to optimize response time Page 8/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information Basic operation: example with a long thin conductor Minisens is a galvanically isolated current transducer. It senses the magnetic field generated by the measured current and transforms it into an output voltage. If the current is bidirectional, Minisens will sense the polarity of the magnetic field and generate a positive or negative output voltage relative to the reference voltage. A simple case is presented which illustrates the current to magnetic field and then to output voltage conversion. A current flowing in a long thin conductor generates a flux density around it: with IP r 0 B= 0 IP (T ) 2 r the current to be measured (A) the distance from the center of the wire (m) the permeability of vacuum (physical constant, 0 = 4.. 10-7 H/m) Figure 8: Minisens orientation to measure the magnetic field generated by a current along a conductor If Minisens is now placed in the vicinity of the conductor (with its sensitivity direction colinear to the flux density B), it will sense the flux density and the output voltage will be: V S = GB B = GB 0 IP IP = 1.2 10 - 4 ( V ) 2 r r where GB is the Minisens magnetic sensitivity (600 V/T) The sensitivity is therefore: G= VS 1.2 10 = IP r -4 (V / A) The next graph shows how the ouput voltage decreases when r increases. Note that the sensitivity also depends on the primary conductor shape. Page 9/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information Sensitivity function of distance (thin and long conductor) Sensitivity (mV/A) 250 200 150 100 50 0 0 1 2 3 4 Conductor to sensor distance (mm) Figure 9: Sensitivity versus the distance between the conductor and the Minisens sensing elements The example above is of limited practical use as most conductors are not round and thin but explains the principles of Minisens operation. The measuring range limit (IPM) is reached when the output voltage (V - V ) reaches 2 V. OUT REF This limit is due to electrical saturation of the output amplifier. The input current or field may be increased above this limit without risk for the circuit. Recovery will occur without additional delay (same response time as usual). The maximum current that can be continuously applied to the transducer (IPM) is only limited by the primary conductor carrying capacity. Page 10/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information Single track on PCB The main pratical configurations will now be reviewed and their main features highlighted. The use of Minisens to measure a current flowing in a track provides the following advanges: Isolation is guaranteed by PCB design. If the primary track is placed on the opposite (bottom) side of the PCB, the isolation can be very high stable and reproducible sensitivity inexpensive large input currents (up to about 100 A). 1 B PCB Ip B B PCB PCB Primary Conductor (Track) Primary Conductor (Track) Figure 10: Principle of Minisens used to measure current in a PCB track Sensitivity function of track to magnetic sensor distance (track 70 microns thick) 1 mm wide track 120 2 mm wide track 3 mm wide track Sensitivity (mV/A) 100 80 60 nominal distance for a top side track 40 nominal distance for a bottom side track with 1.6 mm PCB 20 0 1 1.235 1.5 2 2.5 2.905 3 3.5 track axis to sensor distance (mm) Figure 11: Sensitivity versus track width and versus distance between the track and the Minisens sensing elements Page 11/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information The sensitivity depends on the track width and distance, as shown in figure 11. The maximum current that can be safely applied continuously is determined by the temperature rise of the track. The use of a track with varying width gives the best combination of sensitivity and track temperature rise. The following paragraphs show optimized track shapes for bottom and top side tracks. they are only examples and there could be many others depending on the application requirements. Track bottom side High isolation configuration Track top side Low isolation configuration Track on bottom side 1 B 1 PCB Ip B PCB Ip B B PCB PCB Primary Conductor (Track) Primary Conductor (Track) KIT 5 KIT 9 Creeapage, clearance 8 mm 8 mm Nominal primary current IPN 16 A 30 A (85C ambient, natural convection, Creeapage, clearance 0.4 mm Nominal primary current IPN 16 A (85C ambient, natural convection, 30C track temperature rise) Measuring range IPM 55 A 76 A Sensitivity G 36 mV/A 26 mV/A Track width under IC 3 mm 8 mm Track width elsewhere 10 mm 16 mm A demo board of this G2.00.23.104.0 design is available KIT 4 GE.00.23.108.0 30C track temperature rise) Measuring range IPM 29 A Sensitivity G 68.7 mV/A Track width under IC 3 mm Track width elsewhere 10 mm A demo board of this G2.00.23.103.0 design is available PCB characteristics 1.6 mm / 70 m Cu PCB characteristics 70 m Cu Page 12/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information Multi-turns For low currents (under 10 A), it is advisable to make several turns with the primary track to increase the magnetic field generated by the primary current. As with a single track, it is better to have wider tracks around the Minisens than under it (to reduce temperature rise) Figure 12: Example of multi-turns PCB design Two optimized design examples are presented below. 4 turns bottom side High isolation configuration 3 turns bottom side Low isolation configuration KIT 7 KIT 8 Creeapage, clearance 8 mm Creeapage, clearance 0.4 mm Nominal primary current IPN 5 A Nominal primary current IPN 5 A (85C ambient, natural convection, (85C ambient, natural convection, 30C track temperature rise) 30C track temperature rise) Measuring range IPM 15 A Measuring range IPM 10 A Sensitivity G 126 mV/A Sensitivity G 186 mV/A Track width under IC 0.78 mm Track width under IC 0.78 mm Track width elsewhere 3 mm Track width elsewhere 3 mm A demo board of this A demo board of this GE.00.23.107.0 design is available design is available PCB characteristics 1.6 mm / 70 m Cu PCB characteristics 1.6 mm / 70 m Cu GE.00.23.106.0 Page 13/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information Jumper The use of a jumper and PCB tracks to realize a complete loop around Minisens allows it to have a very high sensitivity for a nominal current of about 10 Amps. B 1 Ip PCB KIT 6 Creepage, clearance Nominal primary current IPN (85C ambient, natural convection, 30C track temperature rise) Measuring range IPM Sensitivity G Track width under IC Track width elsewhere A demo board of this design is available PCB characteristics 1.6 mm / 70 m Cu. 0.4 mm 9A 9A 206 mV/A 3 mm 10 mm GE.00.23.105.0 Jumper Ip PCB Cable or busbar For very large currents (>50A), Minisens can be used to measure the current flowing in a cable or busbar. The position of Minisens relatively to the conductor has to be stable to avoid sensitivity variations. B B Cable or Busbar Ip PCB Ip Busbar PCB Page 14/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Application information Accuracy considerations Several factors influence the output accuracy of Minisens as a current transducer: 1. The sensitivity of the Minisens 2. The distance and shape of the primary conductor 3. The circuit output offset 4. The circuit non-linearity 5. Stray fields The sensitivity of the Minisens is calibrated during production at 600 V/T 3%. As already mentioned, the distance and shape of the primary conductor also influence the sensitivity. No relative movement of the primary conductor to Minisens should be possible. To avoid differences in a production, the position and shape of the primary conductor and circuit should always be identical. The magnetic fields generated by neighbouring conductors, the earth's magnetic field, magnets, etc. are also measured if they have a component in the direction to which Minisens is sensitive (see figure 8). As a general rule, the stronger the field generated by the primary current, the smaller the influence of stray fields and offset. The primary conductor should therefore be designed to maximize the output voltage. For more details on the accuracy calculation, please consult the "Minisens design guide". Page 15/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Performance parameters definition Sensitivity & Linearity Sensitivity: the Sensitivity GB is defined as the slope of the linear regression line for a magnetic field cycle between B mT, where B is the magnetic field for full scale output. Linearity error: for a field strength b in a cycle whose maximum field strength is B, the linearity error is: Error (b) = ((VS (b) - (bGB)) / BGB) x 100 % where VS (b) is the output voltage, relative to the reference voltage, for the field b. The maximum value of Error (b) is given in the electrical data. Temperature coefficient of G: TCG This is refered to 25 degrees. Response and reaction times: The response time tr, and the reaction time tra are shown in figure 13. The primary current rise time is 1 s. V,I 100 % 90 % Ip Minisens outputs Primary current tr 10 % tra t Figure 13: response time tr and reaction time tra Page 16/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Dimensions FHS 40-P/SP600 (in mm) Side view Cross-section Top view XY positioning 150 m Pin connections Pin 1 : Pin 2 : Pin 3 : Pin 4 : Pin 5 : Pin 6 : Pin 7 : Pin 8 : VREF VOUT 0V 5V 0V 0V Standby VOUTFast Mechanical characteristics Notes: Recommended reflow soldering profile All dimensions are in millimeters (angles in degrees) as standard: IPC/JEDEC J-STD-020 revision C Mass Tape and reel quantity * Dimensions do not include mold flash, protrusions or gate burrs (shall 0.08 g 3000 parts not exceed 0.15 per side). ** dimension does not include interleads flash or protrusion (shall not exceed 0.25 per side). *** Dimension does not include dambar protrusion. Allowable dambar protrusion shall be 0.08 mm total in excess of the dimension at maximum material condition. Dambar cannot be located on the lower radius of the foot. Page 17/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com FHS 40-P/SP600 0 - 100A Tape and Reel dimensions REVISIONS LOCK FEATURE 6 PLACES NO. MATTE FINISH THESE AREAS DESCRIPTION DATE LOKREEL MINNEAPOLIS, USA U.S. PAT. 4726534 102.0 REF 330.0 REF SEE DETAIL "A" NOMINAL HUB WIDTH O20.2 MIN O13.0+0.5 -0.2 2.00.5 DETAIL "A" W1 +.6 -.4 W 2 MAX W1 (MEASURED AT HUB) W2 (MEASURED AT HUB) 8mm 8.8 14.2 12mm 12.8 18.2 16mm 16.8 22.2 24mm 24.8 30.2 32mm 32.8 38.2 44mm 44.8 50.2 56mm 56.8 62.2 U.S. PATENT 4726534 - All Dimensions in Millimeters TOLERANCES ASSEMBLED 330mm LOKREEL, 4" HUB (EXCEPT AS NOTED) DECIMAL SCALE FRACTIONAL DRAWN BY CHK'D DATE TRACED APP'D T.S. ANGULAR Notes: 1) 2) 3) MATERIAL NONE 9/11/96 A0911-96-1 10 Sprocket hole pitch cumulative tolerance 0.2 mm Camber in compliance with EIA 481 Pocket position relative to sprocket hole measured as true position of pocket, not pocket hole. All dimensions are in mm. Page 18/18 100727/10 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. N/A DRAWING NO. www.lem.com BY