CAS 25-NP

**Current Transducer CAS series** 

## **I = 6, 15, 25, 50 A** PN 

## **Ref: CAS 6-NP, CAS 15-NP, CAS 25-NP, CAS 50-NP** 

**For the electronic measurement of current: DC, AC, pulsed..., with galvanic isolation between the primary and the secondary circuit.** 

## **Features** 

## **Applications** 

- ●Closed loop (compensated) multi-range current transducer 

- ●Voltage output 

- ●Single supply 

- ●Isolated plastic case material recognized according to UL 94-V0 

- ●Compact design for PCB mounting. 

## **Advantages** 

- ●Very low temperature coefficient of offset 

- ●Very good dv/dt immunity 

- ●LTS compatible footprint 

- ●Reduced height. 

- ●AC variable speed and servo motor drives 

- ●Static converters for DC motor drives 

- ●Battery supplied applications 

- ●Uninterruptible Power Supplies (UPS) 

- ●Switched Mode Power Supplies (SMPS) 

- ●Power supplies for welding applications. 

## **Standards** 

- ●EN 50178 

- ●UL 508 

- ●IEC 61010-1 (safety). 

## **Application Domain** 

- ●Industrial. 

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**CAS series** 

## **Absolute maximum ratings** 

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Parameter Symbol Unit Value<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Value**|
|---|---|---|---|
|||||
|Supply voltage|**V**C|V|7|
|Primary conductor temperature||°C|110|
|Maximum primary current|**I**P max|A|20 x**I**PN|
|ESD rating, Human Body Model (HBM)||kV|4|



Stresses above these ratings may cause permanent damage. Exposure to absolute maximum ratings for extended periods may degrade reliability. 

## **Isolation characteristics** 

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Parameter Symbol Unit Value Comment<br>RMS voltage for AC isolation test 50/60Hz/1 min  V d kV 4.2<br>Impulse withstand voltage 1.2/50 µs V w kV 7.6<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Value**|**Comment**|
|---|---|---|---|---|
|RMS voltage for AC isolation test 50/60Hz/1 min|**V**d|kV|4.2||
|Impulse withstand voltage 1.2/50 µs|**V**w|kV|7.6||
||||||
|Partial discharge extinction voltage @ 10 pC (rms)|**V**e|V|1000||
|Clearance distance (pri. - sec.)|**dCI**|mm|7.7|Shortest distance through<br>air|
|Creepage distance (pri. - sec.)|**dCp**|mm|7.7|Shortest path along device<br>body|
|Creepage distance (pri. .- sec.)|-|mm|6.3|When mounted on PCB<br>with recommended layout|
|Case material|-|-|V0 according<br>to UL 94||
|Comparative tracking index|**CTI**|V|600||
|Application example|-|-|300 V CAT III<br>PD2|Reinforced isolation, non<br>uniform feld according to<br>EN 50178, EN 61010|
|Application example|-|-|600 V CAT III<br>PD2|Simple isolation, non<br>uniform feld according to<br>EN 50178, EN 61010|
|According to UL 508:<br>primary potential involved in Volts RMS AC or DC|-|V|600|For use in a pollution<br>degree 2 environment|



## **Environmental and mechanical characteristics** 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Max**|**Comment**|
|---|---|---|---|---|---|---|
||||||||
|Ambient operating temperature|**T**A|°C|-40||85||
|Ambient storage temperature|**T**S|°C|-55||105||
|Mass|**_m_**|g||9|||
|Standards|EN 50178, IEC 60950-1, IEC 61010-1, IEC 61326-1, UL 508||||||



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8March2012/version 7 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice 

**CAS series** 

## **Electrical data CAS 6-NP** 

At **T** A = 25°C, **V** C = + 5 V, **N** P = 1 turn, **R** L = 10 kΩ, unless otherwise noted. 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal current rms|**I**PN|A||6|||||
|Primary current, measuring range|**I**PM|A|-20|||20|||
|Number of primary turns|**N**P|-||1,2,3|||||
|Supply voltage|**V**C|V|4.75||5|5.25|||
|Current consumption|**I**C|mA||15 +|<br>**I**P(mA)<br> **N**S|20 +|**I**P(mA)<br> **N**S|**N**S= 1731 turns|
|Output voltage|**V**OUT|V|0.375|||4.625|||
|Output voltage @**I**P= 0 A|**V**OUT|V|||2.5||||
|Electrical offset voltage|**V**OE|mV|-10.4|||10.4||100% tested<br>**V**OUT- 2.5 V|
|Electrical offset current<br>referred to primary|**I**OE|A|-0.1|||0.1||100% tested|
|Temperature coeffcient of**V**OUT<br>@**I**P= 0 A|**TCV**OUT|ppm/K||±10||±80||ppm/K of 2.5 V<br>- 40°C .. 85°C|
|Theoretical sensitivity|**Gth**|mV/A||104.2||||625 mV/**I**PN|
|Sensitivity error|εG|%|-0.7|||0.7||100% tested|
|Temperature coeffcient of**G**|**TCG**|ppm/K||||±40||- 40°C .. 85°C|
|Linearity error|εL|% of**I**PN|-0.1|||0.1|||
|Magnetic offset current (10 x**I**PN)<br>referred to primary|**I**OM|A|-0.1|||0.1|||
|Output current noise (spectral<br>density) rms 100 .. 100 kHz<br>referred to primary|ino|µA/Hz½||36||||**R**L= 1 kΩ|
|Peak-peak output ripple at<br>oscillator frequency<br>**f**= 450 kHz (typ.)|**-**|mV||40||160||**R**L= 1 kΩ|
|Reaction time @ 10 % of**I**PN|**t**ra|µs||||0.3||**R**L= 1 kΩ<br>di/dt = 18 A/µs|
|Response time @ 90 % of**I**PN|**t**r|µs||||0.3||**R**L= 1 kΩ<br>di/dt = 18 A/µs|
|Frequency bandwidth (± 1 dB)|**BW**|kHz|200|||||**R**L= 1 kΩ|
|Frequency bandwidth (± 3 dB)|**BW**|kHz|300|||||**R**L= 1 kΩ|
|Overall accuracy|**X**G|% of**I**PN||||2.5|||
|Overall accuracy @**T**A= 85°C|**X**G|% of**I**PN||||4.6|||
|Accuracy|**X**|% of**I**PN||||0.8|||
|Accuracy @**T**A= 85°C|**X**|% of**I**PN||||3.0|||



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## **CAS series** 

## **Electrical data CAS 15-NP** 

At **T** A = 25°C, **V** C = + 5 V, **N** P = 1 turn, **R** L = 10 kΩ, unless otherwise noted. 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal current rms|**I**PN|A||15|||||
|Primary current, measuring range|**I**PM|A|-51|||51|||
|Number of primary turns|**N**P|-||1,2,3|||||
|Supply voltage|**V**C|V|4.75||5|5.25|||
|Current consumption|**I**C|mA||15 +|<br>**I**P(mA)<br> **N**S|20 +|**I**P(mA)<br> **N**S|**N**S= 1731 turns|
|Output voltage|**V**OUT|V|0.375|||4.625|||
|Output voltage @**I**P= 0 A|**V**OUT|V|||2.5||||
|Electrical offset voltage|**V**OE|mV|-7.1|||7.1||100% tested<br>**V**OUT- 2.5 V|
|Electrical offset current<br>referred to primary|**I**OE|A|-0.17|||0.17||100% tested|
|Temperature coeffcient of**V**OUT<br>@**I**P= 0 A|**TCV**OUT|ppm/K||±7.5||±70||ppm/K of 2.5 V<br>- 40°C .. 85°C|
|Theoretical sensitivity|**Gth**|mV/A||41.67||||625 mV/**I**PN|
|Sensitivity error|εG|%|-0.7|||0.7||100% tested|
|Temperature coeffcient of**G**|**TCG**|ppm/K||||±40||- 40°C .. 85°C|
|Linearity error|εL|% of**I**PN|-0.1|||0.1|||
|Magnetic offset current (10 x**I**PN)<br>referred to primary|**I**OM|A|-0.1|||0.1|||
|Output current noise (spectral<br>density) rms 100 Hz .. 100 kHz<br>referred to primary|ino|µA/Hz½||90||||**R**L= 1 kΩ|
|Peak-peak output ripple at<br>oscillator frequency<br>**f**= 450 kHz (typ.)|**-**|mV||15||60||**R**L= 1 kΩ|
|Reaction time @ 10 % of**I**PN|**t**ra|µs||||0.3||**R**L= 1 kΩ<br>di/dt = 44 A/µs|
|Response time @ 90 % of**I**PN|**t**r|µs||||0.3||**R**L= 1 kΩ<br>di/dt = 44 A/µs|
|Frequency bandwidth (± 1 dB)|**BW**|kHz|200|||||**R**L= 1 kΩ|
|Frequency bandwidth (± 3 dB)|**BW**|kHz|300|||||**R**L= 1 kΩ|
|Overall accuracy|**X**G|% of**I**PN||||1.9|||
|Overall accuracy @**T**A= 85°C|**X**G|% of**I**PN||||3.9|||
|Accuracy|**X**|% of**I**PN||||0.8|||
|Accuracy @**T**A= 85°C|**X**|% of**I**PN||||2.7|||



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## **CAS series** 

## **Electrical data CAS 25-NP** 

At **T** A = 25°C, **V** C = + 5 V, **N** P = 1 turn, **R** L = 10 kΩ, unless otherwise noted. 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal current rms|**I**PN|A||25|||||
|Primary current, measuring range|**I**PM|A|-85|||85|||
|Number of primary turns|**N**P|-||1,2,3|||||
|Supply voltage|**V**C|V|4.75||5|5.25|||
|Current consumption|**I**C|mA||15 +|<br>**I**P(mA)<br> **N**S|20 +|**I**P(mA)<br> **N**S|**N**S= 1731 turns|
|Output voltage|**V**OUT|V|0.375|||4.625|||
|Output voltage @**I**P= 0 A|**V**OUT|V||2.5|||||
|Electrical offset voltage|**V**OE|mV|-6.25|||6.25||100% tested<br>**V**OUT- 2.5 V|
|Electrical offset current<br>referred to primary|**I**OE|A|-0.25|||0.25||100% tested|
|Temperature coeffcient of**V**OUT<br>@**I**P= 0 A|**TCV**OUT|ppm/K||±6.5||±60||ppm/K of 2.5 V<br>- 40°C .. 85°C|
|Theoretical sensitivity|**Gth**|mV/A||25||||625 mV/**I**PN|
|Sensitivity error|εG|%|-0.7|||0.7||100% tested|
|Temperature coeffcient of**G**|**TCG**|ppm/K||||±40||- 40°C .. 85°C|
|Linearity error|εL|% of**I**PN|-0.1|||0.1|||
|Magnetic offset current (10 x**I**PN)<br>referred to primary|**I**OM|A|-0.1|||0.1|||
|Output current noise (spectral<br>density) rms 100 Hz .. 100 kHz<br>referred to primary|ino|µA/Hz½||150||||**R**L= 1 kΩ|
|Peak-peak output ripple at<br>oscillator frequency<br>**f**= 450 kHz (typ.)|**-**|mV||10||40||**R**L= 1 kΩ|
|Reaction time @ 10 % of**I**PN|**t**ra|µs||||0.3||**R**L= 1 kΩ<br>di/dt = 68 A/µs|
|Response time @ 90 % of**I**PN|**t**r|µs||||0.3||**R**L= 1 kΩ<br>di/dt = 68 A/µs|
|Frequency bandwidth (± 1 dB)|**BW**|kHz|200|||||**R**L= 1 kΩ|
|Frequency bandwidth (± 3 dB)|**BW**|kHz|300|||||**R**L= 1 kΩ|
|Overall accuracy|**X**G|% of**I**PN||||1.8|||
|Overall accuracy @**T**A= 85°C|**X**G|% of**I**PN||||3.5|||
|Accuracy|**X**|% of**I**PN||||0.8|||
|Accuracy @**T**A= 85°C|**X**|% of**I**PN||||2.5|||



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## **CAS series** 

## **Electrical data CAS 50-NP** 

At **T** A = 25°C, **V** C = + 5 V, **N** P = 1 turn, **R** L = 10 kΩ, unless otherwise noted. 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|
|||||||||
|Primary nominal current rms|**I**PN|A||50||||
|Primary current, measuring range|**I**PM|A|-150|||150||
|Number of primary turns|**N**P|-||1,2,3||||
|Supply voltage|**V**C|V|4.75||5|5.25||
|Current consumption|**I**C|mA||15 +|<br>**I**P(mA)<br> **N**S|20 +<br>**I**P(mA)<br> **N**S|**N**S= 966 turns|
|Output voltage|**V**OUT|V|0.375|||4.625||
|Output voltage @**I**P= 0 A|**V**OUT|V|||2.5|||
|Electrical offset voltage|**V**OE|mV|-5.8|||5.8|100% tested<br>**V**OUT- 2.5 V|
|Electrical offset current<br>referred to primary|**I**OE|A|-0.46|||0.46|100% tested|
|Temperature coeffcient of**V**OUT<br>@**I**P= 0 A|**TCV**OUT|ppm/K|||±6|±60|ppm/K of 2.5 V<br>- 40°C .. 85°C|
|Theoretical sensitivity|**Gth**|mV/A||12.5|||625 mV/**I**PN|
|Sensitivity error|εG|%|-0.7|||0.7|100% tested|
|Temperature coeffcient of**G**|**TCG**|ppm/K||||±40|- 40°C .. 85°C|
|Linearity error|εL|% of**I**PN|-0.1|||0.1||
|Magnetic offset current (10 x**I**PN)<br>referred to primary|**I**OM|A|-0.1|||0.1||
|Output current noise (spectral<br>density) rms 100 Hz .. 100 kHz<br>referred to primary|ino|µA/Hz½||300|||**R**L= 1 kΩ|
|Peak-peak output ripple at<br>oscillator frequency<br>**f**= 450 kHz (typ.)|**-**|mV||5||20|**R**L= 1 kΩ|
|Reaction time @ 10 % of**I**PN|**t**ra|µs||||0.3|**R**L= 1 kΩ<br>di/dt = 100 A/µs|
|Response time @ 90 % of**I**PN|**t**r|µs||||0.3|**R**L= 1 kΩ<br>di/dt = 100 A/µs|
|Frequency bandwidth (± 1 dB)|**BW**|kHz|200||||**R**L= 1 kΩ|
|Frequency bandwidth (± 3 dB)|**BW**|kHz|300||||**R**L= 1 kΩ|
|Overall accuracy|**X**G|% of**I**PN||||1.7||
|Overall accuracy @**T**A= 85°C|**X**G|% of**I**PN||||3.4||
|Accuracy|**X**|% of**I**PN||||0.8||
|Accuracy @**T**A= 85°C|**X**|% of**I**PN||||2.5||



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8March2012/version 7 

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**CAS series** 

## **Typical performance characteristics CAS 6-NP** 

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0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-6 0 6<br>IP (A)<br>)<br>PN<br>Linearity error  (% of I<br>**----- End of picture text -----**<br>


_Figure 1: Linearity error_ 

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7 3.2<br>6 3.1<br>5 3.0<br>4 2.9<br>IP = 6 A<br>3 2.8<br>2 IP 2.7<br>1 VOUT 2.6<br>0 2.5<br>-1 2.4<br>-0.5 0 0.5 1 1.5 2<br>t (µs)<br> (A)   (V)<br>IP OUT<br>V<br>**----- End of picture text -----**<br>


_Figure 3: Step response_ 

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10000<br>1000<br>100<br>10<br>1<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>Frequency (Hz)<br>)<br>½<br> (μA/Hz<br>ino<br>**----- End of picture text -----**<br>


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1 1<br>0.8 IP = 6 A 0<br>0.6 -1<br>0.4 -2<br>0.2 -3<br>0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-1 -9<br>100 1000 10000 100000 1000000<br>Frequency (Hz)<br>Figure 2: Frequency response<br>7 3.2<br>6 3.1<br>5 3.0<br>4 2.9<br>IP = 6 A<br>3 2.8<br>2 IP 2.7<br>1 VOUT 2.6<br>0 2.5<br>-1 2.4<br>-2 0 2 4 6 8 10<br>t (µs)<br>Figure 4: Step response<br>800 3.6<br>600<br>3.4<br>400<br>3.2<br>200<br>0 20 kV/μs 3.0<br>-200<br>VP 2.8<br>-400 VOUT<br>2.6<br>-600<br>-800 2.4<br>-1 0 1 2 3 4 5<br>t (µs)<br>Phase (°)<br>Relative Sensitivity (dB)<br> (A)   (V)<br>IP OUT<br>V<br> (V)<br>P<br> (V)<br>OUT<br>V<br>Primary Voltage V<br>**----- End of picture text -----**<br>


_Figure 5: Input referred noise_ 

_Figure 6: dv/dt_ 

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LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice 

8March2012/version 7 

**CAS series** 

## **Typical performance characteristics CAS 15-NP** 

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**----- Start of picture text -----**<br>
0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-15 0 15<br>IP (A)<br>)<br>PN<br>Linearity error  (% of I<br>**----- End of picture text -----**<br>


_Figure 7: Linearity error_ 

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**----- Start of picture text -----**<br>
1 1<br>0.8 IP = 15 A 0<br>0.6 -1<br>0.4 -2<br>0.2 -3<br>0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-1 -9<br>100 1000 10000 100000 1000000<br>Frequency (Hz)<br>Phase (°)<br>Relative Sensitivity (dB)<br>**----- End of picture text -----**<br>


_Figure 8: Frequency response_ 

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17.5 3.2<br>15 3.1<br>12.5 3.0<br>10 2.9<br>IP = 15  A<br>7.5 2.8<br>5 IP 2.7<br>2.5 VOUT 2.6<br>0 2.5<br>-2.5 2.4<br>-0.5 0 0.5 1 1.5 2<br>t (µs)<br>Figure 9: Step response<br>10000<br>1000<br>100<br>10<br>1<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>Frequency (Hz)<br> (A)   (V)<br>IP OUT<br>V<br>)<br>½<br> (μA/Hz<br>ino<br>**----- End of picture text -----**<br>


_Figure 9: Step response_ 

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17.5 3.2<br>15 3.1<br>12.5 3.0<br>10 2.9<br>IP = 15  A<br>7.5 2.8<br>5 IP 2.7<br>2.5 VOUT 2.6<br>0 2.5<br>-2.5 2.4<br>-2 0 2 4 6 8 10<br>t (µs)<br>Figure 10: Step response<br>800 3.6<br>600<br>3.4<br>400<br>3.2<br>200<br>0 20 kV/μs 3.0<br>-200<br>VP 2.8<br>-400 VOUT<br>2.6<br>-600<br>-800 2.4<br>-1 0 1 2 3 4 5<br>t (µs)<br> (A)   (V)<br>IP OUT<br>V<br> (V)<br>P<br> (V)<br>OUT<br>V<br>Primary Voltage V<br>**----- End of picture text -----**<br>


_Figure 11: Input referred noise_ 

_Figure 12: dv/dt_ 

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LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice 

8March2012/version 7 

**CAS series** 

## **Typical performance characteristics CAS 25-NP** 

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**----- Start of picture text -----**<br>
0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-25 0 25<br>IP (A)<br>)<br>PN<br>Linearity error  (% of I<br>**----- End of picture text -----**<br>


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**----- Start of picture text -----**<br>
1 1<br>0.8 IP = 25 A 0<br>0.6 -1<br>0.4 -2<br>0.2 -3<br>0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-1 -9<br>100 1000 10000 100000 1000000<br>Frequency (Hz)<br>Phase (°)<br>Relative Sensitivity (dB)<br>**----- End of picture text -----**<br>


_Figure 13: Linearity error_ 

_Figure 14: Frequency response_ 

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**----- Start of picture text -----**<br>
29.2 3.2<br>25.0 3.1<br>20.8 3.0<br>16.7 2.9<br>IP = 25 A<br>12.5 2.8<br>8.3 IP 2.7<br>4.2 VOUT 2.6<br>0.0 2.5<br>-4.2 2.4<br>-0.5 0 0.5 1 1.5 2<br>t (µs)<br>Figure 15: Step response<br>10000<br>1000<br>100<br>10<br>1<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>Frequency (Hz)<br> (A)   (V)<br>IP OUT<br>V<br>)<br>½<br> (μA/Hz<br>ino<br>**----- End of picture text -----**<br>


_Figure 15: Step response_ 

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**----- Start of picture text -----**<br>
29.2 3.2<br>25.0 3.1<br>20.8 3.0<br>16.7 2.9<br>IP = 25 A<br>12.5 2.8<br>8.3 IP 2.7<br>4.2 VOUT 2.6<br>0.0 2.5<br>-4.2 2.4<br>-2 0 2 4 6 8 10<br>t (µs)<br>Figure 16: Step response<br>800 3.6<br>600<br>3.4<br>400<br>3.2<br>200<br>0 20 kV/μs 3.0<br>-200<br>VP 2.8<br>-400 VOUT<br>2.6<br>-600<br>-800 2.4<br>-1 0 1 2 3 4 5<br>t (µs)<br> (A)   (V)<br>IP OUT<br>V<br> (V)<br>P<br> (V)<br>OUT<br>V<br>Primary Voltage V<br>**----- End of picture text -----**<br>


_Figure 17: Input referred noise_ 

_Figure 18: dv/dt_ 

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8March2012/version 7 

**CAS series** 

## **Typical performance characteristics CAS 50-NP** 

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**----- Start of picture text -----**<br>
0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-50 0 50<br>IP (A)<br>)<br>PN<br>Linearity error  (% of I<br>**----- End of picture text -----**<br>


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**----- Start of picture text -----**<br>
1 1<br>0.8 IP = 50 A 0<br>0.6 -1<br>0.4 -2<br>0.2 -3<br>0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-1 -9<br>100 1000 10000 100000 1000000<br>Frequency (Hz)<br>Phase (°)<br>Relative Sensitivity (dB)<br>**----- End of picture text -----**<br>


_Figure 19: Linearity error_ 

_Figure 20: Frequency response_ 

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**----- Start of picture text -----**<br>
58.3 3.2<br>50.0 3.1<br>41.7 3.0<br>33.3 2.9<br>IP = 50 A<br>25.0 2.8<br>16.7 IP 2.7<br>8.3 VOUT 2.6<br>0.0 2.5<br>-8.3 2.4<br>-0.5 0 0.5 1 1.5 2<br>t (µs)<br> (A)   (V)<br>IP OUT<br>V<br>**----- End of picture text -----**<br>


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**----- Start of picture text -----**<br>
58.3 3.2<br>50.0 3.1<br>41.7 3.0<br>33.3 2.9<br>IP = 50 A<br>25.0 2.8<br>16.7 IP 2.7<br>8.3 VOUT 2.6<br>0.0 2.5<br>-8.3 2.4<br>-2 0 2 4 6 8 10<br>t (µs)<br> (A)   (V)<br>IP OUT<br>V<br>**----- End of picture text -----**<br>


_Figure 21: Step response_ 

_Figure 22: Step response_ 

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**----- Start of picture text -----**<br>
10000<br>1000<br>100<br>10<br>1<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>Frequency (Hz)<br>)<br>½<br> (μA/Hz<br>ino<br>**----- End of picture text -----**<br>


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**----- Start of picture text -----**<br>
800 3.6<br>600<br>3.4<br>400<br>3.2<br>200<br>0 20 kV/μs 3.0<br>-200<br>VP 2.8<br>-400 VOUT<br>2.6<br>-600<br>-800 2.4<br>-1 0 1 2 3 4 5<br>t (µs)<br> (V)<br>P<br> (V)<br>OUT<br>V<br>Primary Voltage V<br>**----- End of picture text -----**<br>


_Figure 23: Input referred noise_ 

_Figure 24: dv/dt_ 

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8March2012/version 7 

**CAS series** 

## **Maximum continuous DC primary current** 

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**----- Start of picture text -----**<br>
40<br>35<br>CAS 6-NP<br>30<br>25<br>20<br>15<br>10<br>5<br>0<br>0 20 40 60 80 100 120<br>TA (°C)<br>Figure 25:  I P vs  vs  T A for CAS 6-NP  for CAS 6-NP<br>90<br>80<br>70<br>60 CAS 25-NP<br>50<br>40<br>30<br>20<br>10<br>0<br>0 20 40 60 80 100 120<br>TA (°C)<br>  (A)<br>P<br> I<br>  (A)<br>P<br> I<br>**----- End of picture text -----**<br>


_Figure 25:_ _**I** P vs  vs_ _**T** A for CAS 6-NP  for CAS 6-NP_ 

_Figure 27:_ _**I** P vs_ _**T** A for CAS 25-NP_ 

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**----- Start of picture text -----**<br>
90<br>80<br>CAS 15-NP<br>70<br>60<br>50<br>40<br>30<br>20<br>10<br>0<br>0 20 40 60 80 100 120<br>TA (°C)<br>Figure 26:  I P vs  T A for CAS 15-NP<br>160<br>140 CAS 50-NP<br>120<br>100<br>80<br>60<br>40<br>20<br>0<br>0 20 40 60 80 100 120<br>TA (°C)<br>  (A)<br>P<br> I<br>  (A)<br>P<br> I<br>**----- End of picture text -----**<br>


_Figure 28:_ _**I** P vs_ _**T** A for CAS 50-NP_ 

The maximum continuous DC primary current plot shows the boundary of the area for which all the following conditions are true: 

- **I** < **I** P PM 

- Junction temperature Tj < 125 °C 

- Primary conductor temperature < 110 °C 

- Resistor power dissipation < 0.5 x rated power 

## **Frequency derating** 

## **AC Derating** 

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1.25<br>1<br>0.75<br>0.5<br>0.25<br>0<br>10 100 1k 10k 100k 1M<br>f (Hz)<br>max  DC current<br>max RMS AC current /<br>**----- End of picture text -----**<br>


_Figure 29: Maximum RMS AC primary current / maximum DC primary current vs frequency_ 

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**CAS series** 

## **Performance parameters definition** 

## **Ampere-turns and amperes** 

The transducer is sensitive to the primary current linkage QP (also called ampere-turns). 

QP= **N** P **I** P(At) 

Where **N** P **I** P the number of primary turn (1, 2 or 3 depending on the connection of the primary jumpers) 

Caution: As most applications will use the transducer with only one single primary turn ( **N** P = 1), much of this datasheet is written in terms of primary current instead of current linkages. However, the ampere-turns (A-t) unit is used to emphasis that current linkages are intended and applicable. 

## **Transducer simplified model** 

The static model of the transducer at temperature **T** A is: **V** = G Q + error OUT P 

In which error = 

**V** OE + **V** OT ( **T** A) + εG ·QP·G + εL(QPmax)·QPmax·G + **TCG** ·( **T** A-25)·QP· **G** 

With: QP = **N** P **I** P :the input ampere-turns (At) Please read above warning. QPmax :the maxi input ampere-turns that have been applied to the transducer (At) **V** OUT :the secondary voltage (V) **T** A :the ambient temperature (°C) **V** OE :the electrical offset voltage (V) **V** OT( **T** A) :the temperature variation of **V** O at temperature **T** A (V) **G** :the sensitivity of the transducer (V/At) εG :the sensitivity error εL (QPmax) :the linearity error for QPmax 

## **Sensitivity and linearity** 

To measure sensitivity and linearity, the primary current (DC) is cycled from 0 to **I** P, then to - **I** P and back to 0 (equally spaced **I** The sensitivity G is defined as the slope of the linear  P/10 steps). regression line for a cycle between ± **I** PN. 

The linearity error εL is the maximum positive or negative difference between the measured points and the linear regression line, expressed in % of **I** PN. 

## **Magnetic offset** 

The magnetic offset current **I** OM is the consequence of a current on the primary side (“memory effect” of the transducer’s ferro-magnetic parts). It is included in the linearity figure but can be measured individually. It is measured using the following primary current cycle. **I** OM depends on the current value **I** P1. 

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**----- Start of picture text -----**<br>
I OM = VOUT ( t 1) − 2 VOUT ( t 2 ) ⋅ Gth 1<br>IP (DC)<br>IP1<br>t2<br>0 A<br>                    t1                         t<br>-IP1<br>**----- End of picture text -----**<br>


_Figure 30: Current cycle used to measure magnetic and electrical offset (transducer supplied)_ 

This model is valid for primary ampere-turns QP between 

-QPmax and +QPmax only. 

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**CAS series** 

## **Performance parameters definition (continued)** 

## **Electrical offset** 

The electrical offset voltage **V** OE can either be measured when the ferro-magnetic parts of the transducer are: 

- ●completely demagnetized, which is difficult to realize, 

- ●or in a known magnetization state, like in the current cycle shown in figure 30. 

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The temperature variation _**V**_ OT of the electrical offset voltage **V** is the variation of the electrical offset from 25°C to the OE considered temperature: 

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Note: the transducer has to be demagnetized prior to the application of the current cycle (for example with a demagnetization tunnel). 

## **Response and reaction times** 

The response time tr and the reaction time tra are shown in figure 31. 

Both depend on the primary current di/dt. They are measured at nominal ampere-turns. 

**==> picture [170 x 119] intentionally omitted <==**

**----- Start of picture text -----**<br>
I<br>100 %<br>90 %<br>VOUT<br>Ip<br>tr<br>10 %<br>t r a t<br>**----- End of picture text -----**<br>


_Figure 31: Response time tr and reaction time  tra_ 

## **Overall accuracy** 

The overall accuracy at 25°C **X** G is the error in the - **I** PN .. + **I** PN range, relative to the rated value **I** PN. It includes: 

- ●the electrical offset **V** OE 

- ●the sensitivity error εG 

- ●the linearity error εL (to **I** PN) 

The magnetic offset is part of the overall accuracy. It is taken into account in the linearity error figure provided the transducer has not been magnetized by a current higher than **I** PN. 

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_Figure 32: Test connection_ 

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8March2012/version 7 

**CAS series** 

## **Application information** 

## **Filtering and decoupling** 

## **Supply voltage V** C 

## **Output V** OUT 

The fluxgate oscillator draws current pulses of up to 30 mA at a rate of ca. 900 kHz. Significant 900 kHz voltage ripple on **V** C can indicate a power supply with high impedance. At these frequencies the power supply rejection ratio is low, and the ripple may appear on the transducer output **V** OUT and reference **V** REF. The transducer has internal decoupling capacitors, but in the case of a power supply with high impedance, it is advised to provide local decoupling (100 nF or more, located close to the transducer). 

## **Total Primary Resistance** 

The primary resistance is 0.72 mΩ per conductor 

In the following table, examples of primary resistance according to the number of primary turns. 

The output **V** OUT has a very low output impedance of typically 2 Ohms; it can drive 100 pF directly.  Adding series Rf = 100 Ohms allows much larger capacitive loads. Empirical evaluation may be necessary to obtain optimum results. The minimum load resistance on **V** is 1 kOhm. OUT 

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|Number of<br>primary turns|Primary<br>resistance<br>**R**P[ mW]|R|ecommended<br>connections|
|---|---|---|---|
|1|0.24|1<br>IN        1|0        9        8       OUT<br>23|
|2|1.08|1<br>IN        1|0        9        8        OUT<br>2        3|
|3|2.16|1<br>IN        1|0        9         8        OUT<br>2        3|



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8March2012/version 7 

**CAS series** 

## **CAS Series, PCB footprint** 

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## **Assembly on PCB** 

- ●Recommended PCB hole diameter 1.3 mm for primary pin 

0.8 mm for secondary pin 

- ●Maximum PCB thickness 

- ●Wave soldering profile No clean process only. 

2.4 mm maximum 260°C for 10 s 

## **Safety** 

This transducer must be used in limited-energy secondary circuits according to IEC 61010-1. 

This transducer must be used in electric/electronic equipment with respect to applicable standards and safety requirements in accordance with the manufacturer’s operating instructions. 

Caution, risk of electrical shock 

When operating the transducer, certain parts of the module can carry hazardous voltage (eg. primary busbar, power supply). Ignoring this warning can lead to injury and/or cause serious damage. This transducer is a build-in device, whose conducting parts must be inaccessible after installation. A protective housing or additional shield could be used. Main supply must be able to be disconnected. 

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8March2012/version 7 

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**CAS series** 

**Dimensions CAS Series** (in mm. General linear tolerance ± 0.25 mm) 

## **Connection** 

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8March2012/version 7