Current Transducer CDSR 0.07-TP

IP R N = 70 mA

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

● Open loop current transducer

Complies with applications using thesestandards● Voltage and SPI digital output● IEC 61851-1: 2017

● Single supply voltage 3.3 V● IEC 62752: 2016

● PCB mounting● IEC 62955: 2018

● Embedded primary jumpers.

● UL 2231-1: 2012

Advantages● UL 2231-2: 2012

Features● UL 2594: 2016.

● Very low error at small currents● High overload capability

Application Domain● High insulation capability● Residential.

● Test winding.

Applications● Leakage current measurement in an IC-CPD in-cable(mode 2) and for wall boxes (mode 3) contact andprotection device● Single phase nominal current up to ±32 A RMS.

N° 97.V4.Q5.000.0
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CDSR 0.07-TP
Safety⚠

CautionIf the device is used in a way that is not specified by the manufacturer, the protection provided by the device may be compromised.
Always inspect the electronics unit and connecting cable before using this product and do not use it if damaged.
Mounting assembly shall guarantee the maximum primary busbar temperature, fulfill clearance and creepage distance, minimize
electric and magnetic coupling, and unless otherwise specified can be mounted in any orientation
The plastic housing is conform to IK06 level (1 Joule). The device was certified for indoor use only and at an altitude below 2000 m.

Caution, risk of electrical shock
This transducer must be used in limited-energy secondary circuits SELV according to IEC 61010-1, in electric/electronic equipmentwith respect to applicable standards and safety requirements in accordance with the manufacturer’s operating specifications.
When operating the transducer, certain parts of the module can carry hazardous voltage (e.g. primary busbar, power supply).
De-energize all circuits and hazardous live parts before installing the product.
All installations, maintenance, servicing operations and use must be carried out by trained and qualified personnel practicing
applicable safety precautions.
If the transducer is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired.
Ignoring this warning can lead to injury and/or cause serious damage.
This transducer is a build-in device, whose hazardous live parts must be inaccessible after installation.
This transducer must be mounted in a suitable end-enclosure and its measuring jumpers must be at some point in the final
installation protected behind a properly dimensioned circuit breaker that can be easily accessed by the end user of the application.
Use caution during installation and use of this product; high voltages and currents may be present in circuit under test.
Main supply must be able to be disconnected.
Never connect the output to any equipment with a common mode voltage to earth greater than 30 volts.
Always wear protective clothing and gloves if hazardous live parts are present in the installation where the measurement is carriedout.
This transducer is a built-in device, not intended to be cleaned with any product. Nevertheless if the user must implement cleaning
or washing process, validation of the cleaning program has to be done by himself.

		

ESD susceptibility

The product is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.
Do not dispose of this product as unsorted municipal waste. Contact a qualified recycler for disposal.
Although LEM applies utmost care to facilitate compliance of end products with applicable regulations during LEM productdesign, use of this part may need additional measures on the application side for compliance with regulations regarding EMC andprotection against electric shock. Therefore LEM cannot be held liable for any potential hazards, damages, injuries or loss of life
resulting from the use of this product.

Underwriters Laboratory Inc. recognized component"This Arrow indicates the positive residual current measurement"
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CDSR 0.07-TP
Absolute maximum ratings
Parameter

Symbol

Unit

Value

Maximum supply voltage±UC max

V

3.6

Maximum primary conductor temperature

TB max°C

100

Maximum withstand primary peak current

ÎP max

A

3300

Electrostatic discharge voltage (HBM - Human Body Model)

UESD HBMkV

6

Absolute maximum ratings apply at 25 °C unless otherwise noted.
Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum ratings for extended periods may degrade reliability.

UL 508: Ratings and assumptions of certification
File # E189713 - Vol. 2.

Standards● CSA C22.2 NO. 14-10 INDUSTRIAL CONTROL EQUIPMENT - Date 2011/08/01● UL 508 STANDARD FOR INDUSTRIAL CONTROL EQUIPMENT - Date 2013
● UL 61010

Ratings
Parameter

SymbolPrimary involved potential

Unit

Value

V RMS

300

Maximum surrounding air temperature

TA

°C

85

Primary current

IP

A

32

Secondary supply voltage

UC

V DC

3.3

Output voltage

Uout

V

0 to 3.3

Conditions of acceptability
When installed in the end-use equipment, consideration shall be given to the following:
1 - These devices must be mounted in a suitable end-use enclosure.
2 - The terminals have not been evaluated for field wiring.
3 - The CDSR xx-TP Series shall be used in a pollution degree 2 environment or better.
4 - Low voltage circuits are intended to be powered by a circuit derived from an isolating source (such as a transformer, opticalisolator, limiting impedance or electro-mechanical relay) and having no direct connection back to the primary circuit (otherthan through the grounding means).The maximum current supplied to the device must be protected/limited to a maximum of
5 Amperes.
5 - These devices are intended to be mounted on the printed wiring board of the end-use equipment (with a minimum CTI of 100).
6 - CDSR xx-TP Series: based on results of temperature tests, in the end-use application, a maximum of 110°C cannot be
exceeded on the primary jumper.
7 - Primary feeder of the devices shall be connected after an overvoltage device or system which has been evaluated by theStandard for Transient Voltage Surge Suppressors, UL 1449 with a maximum clamping voltage of 6 kV.

Marking
Only those products bearing the UL or UR Mark should be considered to be Listed or Recognized and covered under UL’s FollowUp Service. Always look for the Mark on the product.

Performances
All described performances are valid for the whole temperature range at UC = 3.3 V, unless otherwise noted.

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CDSR 0.07-TP
Insulation coordination
Parameter

SymbolUnit≤ Value

RMS voltage for AC insulation test, 50 Hz, 1 min

Ud

kV

3.3

According to IEC 60664

Impulse withstand voltage 1.2/50 μs

UNi

kV

6

According to IEC 60664

Partial discharge RMS test voltage (qm < 10 pC)

Ut

V

825

According to IEC 60664

Clearance (pri. - sec.)

dCI

mm

13.2

Shortest distance through air

Creepage distance (pri. - sec.)

dCp

mm

13.2

Shortest path along device body

Clearance (pri. - pri.)

dCI

mm

8.9

Shortest distance through air

Creepage distance (pri. - pri.)

dCp

mm

8.9

Shortest path along device body

Case material

-

-

V0

According to UL 94

Comparative tracking index

CTI

Application example
RMS voltage line-to-neutral

Comment

600
V

300

Reinforced insulation according toIEC 60664-1 or IEC 61010-1
CAT III, PD2

Environmental and mechanical characteristics
Parameter

SymbolUnit

Min

Ambient operating temperature

TA

°C

−40

85

Ambient storage temperature

TA st

°C

−50

85

Relative humidity

RH

%

85

Mass

m

g

19

Typ

Max

Comment

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CDSR 0.07-TP
General electrical data (see Min, Max, typ, definition paragraph in page 6)
Parameter

SymbolUnit

Primary nominal residual RMS current

IP R NmA

Primary residual current, measuring range

IP R M

mA−150

Supply voltage ⎓

UC

V

3.26

Current consumption ⎓IC

mA

Electrical offset current referred to primary

IO E

mA

Temperature coefficient of IO E referred to primary

TCIO EµA/K

Magnetic offset current (@ IP R = 250 A)

IO M

mA

Primary current common mode rejection ratio

dB

Min

Typ

Max

Comment

70
150
3.3

3.33

Note 1)

50
2
−5.5

5.5

For digital output−8

8

For analog output (taking into
account laboratory equipment
dispersion)

0.6
Common mode current 32 A
RMS. Residual current 0 mA

79

Analog output performances (common mode current = 0 A, −40 ... +85 °C, UC = 3.3 V)
Parameter

SymbolUnit

Min

Nominal sensitivity

SN

V/A

8.79

RMS noise current 1 Hz ... 2 kHz
referred to primary

Ino

mA

0.11

Delay time to 90 % of the final output value for IP N step

tD 90

ms

Frequency bandwidth (−3 dB)

BW

kHz

Sum of sensitivity and linearity error 0 < IP < 6 mA

εS L

mA

−0.5

0.5

Sum of sensitivity and linearity error 6 ≤ IP ≤ 10 mA

εS L

mA

−1

1

Sum of sensitivity and linearity error 10 mA < IP

εS L

% IP

−10

10

Typ

Max

Comment@ 25 °C12
Measurement integration time
10 NPLC (50 Hz)

Digital high accuracy output performances (Common mode current = 0 A, −40 ... +85 °C, UC = 3.3 V)
Parameter

SymbolUnit

Nominal sensitivity

SN

LSB/mASum of sensitivity and linearity error 0 < IP < 6 mA

εS L

mA

−0.5

0.5

Sum of sensitivity and linearity error 6 ≤ IP ≤ 10 mA

εS L

mA

−1

1

−10

10

Sum of sensitivity and linearity error 10 mA < IP

εS L

% IP

Delay time to 90 % of the final output value for IP N step

tD 90

ms

Frequency bandwidth (−3 dB)

BW

Hz

Min

Typ

Max

Comment

87.99

40

Measurement integration time
10 NPLC (50 Hz)
Not including SPI time frame

10

Digital high bandwidth output performances (Common mode current = 0 A, −40 ... +85 °C, UC = 3.3 V)
Parameter

SymbolUnit

Min

Nominal sensitivity

SN

LSB/mASum of sensitivity and linearity error 0 < IP < 6 mA

εS L

mA

−1

1

Sum of sensitivity and linearity error 6 ≤ IP ≤ 10 mA

εS L

mA

−1

1

Sum of sensitivity and linearity error 10 mA < IP

εS L

% IP

−10

10

Delay time to 90 % of the final output value for IP N step

tD 90

ms

Frequency bandwidth (−3 dB)

BW

kHz

Typ

Max

Comment

87.99

1

Measurement integration time
2 NPLC (50 Hz)
Not including SPI time frame

2

Note: 1) The sensitivity of the transducer depends on the power supply (UC) accuracy. A variation of 1 % of UC may lead to a sensitivity drift of 1 %.
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CDSR 0.07-TP
Definition of typical, minimum and maximum values
Minimum and maximum values for specified limiting and safety conditions have to be understood as such as well as values shownin “typical” graphs.
On the other hand, measured values are part of a statistical distribution that can be specified by an interval with upper and lower
limits and a probability for measured values to lie within this interval.
Unless otherwise stated (e.g. “100 % tested”), the LEM definition for such intervals designated with “min” and “max” is that theprobability for values of samples to lie in this interval is 99.73 %.
For a normal (Gaussian) distribution, this corresponds to an interval between −3 sigma and +3 sigma. If “typical” values are notobviously mean or average values, those values are defined to delimit intervals with a probability of 68.27 %, corresponding to aninterval between −sigma and +sigma for a normal distribution.
Typical, maximal and minimal values are determined during the initial characterization of the product.

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CDSR 0.07-TP
Digital signals electrical parameters
Parameter

Symbol

Unit

Min

Uin L

V

−0.3

0.8

2

UC +

Input logic low

Typ

Max

Input logic high

Uin H

V

Output logic low

Uout LV

Output logic highUout HV

UC − 0.4

Sink / drive output maximum current

Iout max

mA−4

SymbolUnit

Min

Start-up time

tstartms

Minimum reset timetres minµs

5Frequency of fault output

fout fault

kHz

11

21

Fault signal threshold

ITh

mA

152

175

Fault signal reaction time

tFaultµs

Comment

0.2

0.4

4

General switching parameters
Parameter

Typ

Max

Comment100

Also valid after a reset pulse

200

Serial interface switching parameters and format
Parameter

Symbol

Unit

Min

Delay to valid SCLKtSS SCLK

ns

100

Delay time, final SCLK falling edge to
SS rising edgetSCLK SS

ns

100

Pulse duration, SS high

tSS H

ns

200

SCLK period

tper SCLK

ns

250

Pulse duration, SCLK hightPW SCLK H

ns

100

Pulse duration, SCLK lowtPW SCLK L

ns

100

Hold time, SCLK rising edge to
MISO invalid

thold MISO

ns

0

Typ

Max

CommenttSS H

SStSS SCLK

tper SCLKtPW SCLK H

tSCLK SSSCLKtPW SCLK L

MISO

Hi-Z

tSCLK MISOtSS MISO D

thold MISOtSCLK SCLKtSS MISO Z
Hi-Z

Figure 1

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CDSR 0.07-TP

SPI Communication

Normal operation
SPI word N°1

SPI word N°2

SPI CRC BYTE

16 bits word N°1 high bandwidth

16 bits word N°2
high accuracy

Error control

SPI word N°2

SPI CRC BYTE

Don't care

Error control

Overcurrent situation/HW fault situation
SPI word N°1

All '1'

Bit Nb 15

6

All '1'alert for current
measure error

5

4

3

2

= '0'
= '0'
RFU1* RFU0*

= '1'
HW
Fault

= '0'

* RFU = Reserved for Future Use** see "Fault signal threshold" min/max values.

1

0

= '1'
= '1'
out of criticalrange overload
residual residual
current** current

SPI management
The transducer's SPI is defined as mode 1 (CPOL = 0 , CPHA = 1, CKE/NCPHA = 0).
The transducer will be always in slave configuration and half-duplex communication.
The Chip Select and Serial Clock must be generated by the master (User).
The dynamic time parameter for the SPI communication are indicated in a parameter table (see above page for more details).
The transducer complete SPI command is composed of 5 bytes, defined as follows:-2 bytes Word No1: digital high-Bandwidth output.
-2 bytes Word No2: digital high-Accuracy output.
-1-byte Checksum CRC error detection:
The 1-byte CRC-8 Error detection is computed using the CRC-8-CCITT polynomial :x8 + x 2 + x + 1
Each of the 5 bytes from the SPI data frame will have to be fed (Most Significant Byte first) to a “crc8” function as in the hereunder pseudo-code.
Note that the initial CHECKSUM value is set to 0xFF:
		CHECKSUM = 0xFF;
		CHECKSUM = crc8(CHECKSUM, SPI_BYTE_1);
		
CHECKSUM = crc8(CHECKSUM, SPI_BYTE_2);
		
CHECKSUM = crc8(CHECKSUM, SPI_BYTE_3);
		
CHECKSUM = crc8(CHECKSUM, SPI_BYTE_4);
		
CHECKSUM = crc8(CHECKSUM, SPI_BYTE_5);
The expected CHECKSUM value at the end shall be 0x00 if no transmission error occurred.
The crc8 function must be coded in the following way (example given C language):unsigned char crc8( unsigned char crc_in, unsigned char data_in){
unsigned char i;
unsigned char data;
data = crc_in ^ data_in;}for ( i = 0; i < 8; i++ ) {if (( data & 0x80 ) != 0 ) {data <<= 1;
data ^= 0x07;} else {data <<= 1;}}
return data;

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CDSR 0.07-TP
For reference, here is the CRC-8 calculation results for an example SPI data frame:-- SPI data frame content:
SPI_BYTE_1 = 0x83
SPI_BYTE_2 = 0x20
SPI_BYTE_3 = 0xE3
SPI_BYTE_4 = 0x96
SPI_BYTE_5 = 0x0E-- checksum calculation:
CHECKSUM = 0xFF;
crc8(0xFF, 0x83) => CHECKSUM = 0x73
crc8(0x73, 0x20) => CHECKSUM = 0xBE
crc8(0xBE, 0xE3) => CHECKSUM = 0x94
crc8(0x94, 0x96) => CHECKSUM = 0x0E
crc8(0x0E, 0x0E) => CHECKSUM = 0x00
The final CHECKSUM value = 0x00: There were no communication error.

Error definition
Digital output
The Transducer detects 3 potential hazardous situations:1)
“out-of-range residual current” (measured residual current higher than specified Fault Signal threshold. Internally thetransducer is still capable of calculating residual current as in normal operation, but without guaranteeing error min/max
tolerance)2)
“critical residual current overload” (in this case, the residual current is high enough for preventing the transducer to function
correctly and calculate any residual current).
3)
“HW fault” (when the internal HW self check has raised an error flag).
This flag will be kept raised until the next device power cycle.
When any of above error are detected, the SPI command changes based on following definition:*16-bits word N°1:
-vector slice bit 15 -MSB- down to bit 6: are set to logic '1' value.
-bit 5: don’t care, reserved for future use.
-bit 4: don’t care, reserved for future use.
-bit 3: set to logic ‘1’ when “HW fault” is detected.
-bit 2: set to logic ‘0’ value.
-bit 1 : set to logic ‘1’ value when “out-of-range residual current” is measured.
-bit 0: set to logic ‘1’ value when “critical residual current overload” is detected.
* 16-bits word N°2: High accuracy stream. This data should not be considered in the event of an error detection.
* 8-bits CRC byte: Error control byte.
Here below an example of error communication where only the first 16 bits have been represented (in this example, a residual
current out of range has been detected):
BIT NUMBER

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

BIT VALUE

1

1

1

1

1

1

1

1

1

1

0

0

0

0

1

0

Analog output
The same 16-bit word N°1 is the input value of the First-Order Sigma-Delta modulator used for the analog output (see pin 3 and6 definition).
Therefore, error can also be detected by the analog output.

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Performance parameters definition
Delay times

Magnetic offset referred to primary
The magnetic offset current IO M is the consequence of a current
on the primary side (“memory effect” of the transducer’s ferromagnetic parts). It is measured using the following primary
current cycle. IO M depends on the current value IP R ≥ IP R N.

The delay time tD 10 to 10 % and the delay time tD 90 @ 90 % withrespect to the primary are shown in the next figure.
Both slightly depend on the primary current di/dt.
They are measured at nominal current.
I

Primary current cyclewith KOL = 1 .. 10

IP R /(K OL· IP N)

1

100 %
90 %

Uout

IP
0

-1

tD 90
10 %

1

2

3

4

tD 10

5

t

Step

KOL: Overload factor
Figure 2 Current cycle used to measure magnetic and electrical offset (transducer supplied)

IO M =

Figure 3: tD 10 (delay time to 10 %) and tD 90 (delay time @ 90 %).

IP R ( 3) − IP R (5)2Electrical offset referred to primary
Using the current cycle shown in figure 2, the electrical offset
current IO E is the residual output referred to primary when the
input current is zero.

IO E =IP R (3) + IP R (5)2

The temperature variation IO T of the electrical offset current
IO E is the variation of the electrical offset from 25 °C to theconsidered temperature.

IO=
T (T ) I O E (T ) − I O E (25 °C)

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A

CDSR 0.07-TP
CDSR typical mounting and interfacing
primary jumpers
14

470R

P_In

P_Out

N_In

N_Out

11

Positive Residual Current

1

Test voltage source

13

12

2

PTVS4V5D1BL
or equivalent **GND
Analog_pos

Analog measurements

4k7*

4k7*

33R

Analog_neg
4k7*

4k7*

1nF*

1nF*

33R
33R
33R
33R

1nF*

1nF*

GND

1
2
3
4
5
6
7
8
9
10

Digital measurements* To be placed as close as possible to the transducer** Equivalence with PTVS4V5D1BL must respect following criteria:-Robustness against IEC 61000-4-5 8/20 µs current waveform.
-Maximum clamping voltage < 20V under 8/20us waveform test.
-Breakdown voltage / Reverse standoff voltage > 4V.
-Bidirectionnal protection.

Test_in
GND
Analog_pos
Uc
RESET
Analog_neg
Fault
SS
SCLK
MISO

B

CDSR-TPUc

100nF*

47uF*

10nF*

GND

Pin N°

Function1

Test_in

2

GND

3

Analog_pos

4

UC

5

Reset

6

Analog_neg

7

Fault

8

SS

9

SCLK

10

MISO

C

D

2 2
3

4

5

6

7

8

* Pin description:
Pin No 1 'Test_in':

This pin is connected to a 10-turns coil. It permits the user to check periodically the transducer
performance by injecting a precise current through the pin.The other coil end terminal is connected to thetransducer ground.
Pin No 2 'GND':
Ground.
Pin No 3 'Analog_pos': 48 MHz Sigma-Delta bitstream to be filtered.
Pin No 4 'UC':
Power supply.
Pin No 5 'Reset':
Active low-level reset signal. Please refer to Start-up time (tstart) for nominal operation.
Pin No 6 'Analog_neg': Inverted signal of pin No 3 'Analog_pos'.
Pin No 7 'Fault':
See "Fault pin Signal" paragraph page 14.
Pin No 8 'SS':
SPI active low-level Chip Select signal.
Pin No 9 'SCLK':SPI Serial Clock signal.
Pin No 10 'MISO':
SPI MISO signal.
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CDSR 0.07-TP

Example of CDSR output readings
Analog output
The analog current measurement is provided on pin 3 and 6 by a differential 48 Mhz Sigma-Delta bitstream to be filtered.
User must apply identical low-pass filtering to both outputs. The first stage (R = 4.7k/C = 1 nF) of a 3rd order hardware low passfilter is already embedded into the transducer. 2 last stages are added for analog output measurements. Refer to “CDSR typicalmounting and interfacing” for typical HW design.
The cutoff frequency of the described filter is 6.4 kHz, compatible with a 2 kHz output bandwidth.
Primary residual current conversion from analog samples is described in below equation:
Primary residual current [ mA ] =(analog positive [ mV ] − analog negative [ mV ] − initial offset compensation [ mV ]Nominal sensitivity [ mV / mA]

Initial analog offset compensation:
The first current measurement done after the transducer start-up should be used for an initial offset compensation.
Consecutive transducer residual current reading must be compensated by the initial offset.
Here below an example of reading operation:
After start-up, residual current I primary = 0 mA (user must be certain there is no residual current when initial offset compensation
is applied).
Analog voltage reading (measurement should ideally be integrated over 10 NPLC):
U (analog_pos) − U (analog_neg) = U0 = 2.2 mV.
Injected residual current I primary = 10 mA.
New analog voltage reading: U (analog_pos) − U (analog_neg) = U1 = 90 mV.
After applying initial offset compensation
U compensated = U1 − U0 = 87.8 mV.
Conversion to primary current:
I = U compensated / 8.79 [mV/mA] = 9.984 mA.

Digital output
The SPI’s digital data-frame provides the user with 2 measurements 16 bits words: “High bandwidth” and “High accuracy”.
The high accuracy word (limited to 10 Hz bandwidth) can be used for DC measurement.
The high bandwidth can be used for AC measurement.
While both words have the exact same source of data, the fundamental difference between the 2 words is their respective
bandwidth. The "high accuracy" word, with a 10 Hz bandwidth is the digitally filtered image of the "high bandwidth" word of 2 kHz
bandwidth. The "High accuracy" word can be used to subtract the DC component from the residual current measurement of the"high bandwidth" word. Therefore, the "high accuracy" word should be used to detect smooth DC residual currents while the "highbandwidth" should rather be used to measure and compute AC RMS residual currents.
The SPI’s digital samples are coded on a 16 bits full-scale (i.e from 0LSB to 65535LSB). Because both positive and negative
residual currents can be measured by the transducer, the 0 mA residual current value is centered @ 50 % of the full scale216= 32768).
(
2
Therefore the SPI’s digital samples must always be subtracted with 32768LSB before converting the value into primary residual
current as described in below equation:
Here below an example of reading operation for the digital high-bandwidth value:

Primary residual current [ mA ] =(Digital sample [ LSB ] − 32768) − initial offset compensation [ LSB ]Nominal sensitivity [ LSB / mA]

After start-up,
I primary = 0 mA
‘Digital sample’ D0 = 32814 LSB (the 16-bits word converted to decimal)216= 32768)
Subtracting center value 50 % of 16 bits full-scale (2
D = D − 32768 = 46 LSB.
10

Conversion to primary current (ignoring initial offset compensation value for the sake of this example):I = 46 LSB / 87.99 LSB/mA = 0.522 mA
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CDSR 0.07-TP
Initial digital offset compensation:
Likewise the analog output reading, an initial offset compensation must be applied onto the digital stream after each transducer
start-up. It is strongly recommended to perform initial offset compensation based on the “high accuracy” stream.
Here below an example of reading operation:
After start-up, residual current I primary = 0 mA (user must be certain there is no residual current when initial offset compensation
is applied).
Digital "High accuracy" stream sampling(sampling should ideally be performed over 10 NPLC and then averaged):
Digital sample −32768 = D0 = 45 LSB = initial offset compensation value.
Injected residual current I primary = 10 mA.
New digital “High bandwidth” and “High accuracy” readings:
High bandwidth sample −32768 = D1 −32768 = 920 LSBHigh accuracy sample −32768 = D2 −32768 = 923 LSB.
After applying initial offset compensation :High bandwidth sample offset compensated = 920 − 45 = 875 LSBHigh accuracy sample offset compensated = 923 − 45 = 878 LSB.
Conversion to primary current:High bandwidth primary current sample =High accuracy primary current sample =875 LSB= 9.94 mA
87.99 LSB / mA

878 LSB= 9.98 mA
87.99 LSB / mA

General recommendations for analog and digital sampling rates:
Both analog stream and “High bandwidth” digital stream have a 2 kHz bandwidth.
It is recommended to acquire samples at a minimum rate of 8 kSa/s or even further for proper RMS calculations.
This can be achieved using DMA-driven SPI/analog acquisition HW so such feature should be strongly considered on a systemlevel.

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LEM International SA
Route du Nant-d’Avril, 152
1217 Meyrinwww.lem.com

CDSR 0.07-TP
Fault-pin Signal
Dynamic diagnostic signal: when a fault is detected the signal remains in any steady state (can be a logic low (0) or high (1)).
Detected faults:● Over-current● Critical over-current● Internal hardware self-test

Figure 4: Fault-pin signal illustration“Test-in” pin
The “Test in” pin is connected to a 10 turns coil inside the transducer: 1 mA injected to this pin will result in 10 mA measurement.
This enables users to test the transducer.
Due to transformer effect a high impedance source is required to generate the test current.
Below an example of a 3.3 mA current generation in the test coil.

Figure 5: "Test-in" pin illustration
It is also required to connect a bidirectional protection device in order to protect the user PCBA against hazardous transient highpulse current through the primary jumper.
Standard Transient Voltage suppressor could accomplish this function (voltage rating to be defined based on specific user
application but has to be > 4 V not to perturbate the transducer proper functioning).
See CDSR typical mounting and interfacing on page 11.

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LEM International SA
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1217 Meyrinwww.lem.com

CDSR 0.07-TP
PCB footprint

Note:

The dimension of customer PCB tracks (width & thickness) and the LEM transducer’s primary jumpers are linked and can
influence on each other regarding thermal exchanges and self heating.

Assembly on PCB● Recommended PCB hole diameter			● Recommended primary via ring diameter:● Wave soldering profile
No clean process only

⌀ 3.0 mm +0.15 mm/−0mm for primary pin⌀ 1.4 mm +0.15 mm/−0 mm for secondary pin
min 3.6 mm

maximum 260 °C, 10 s

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LEM International SA
Route du Nant-d’Avril, 152
1217 Meyrinwww.lem.com

CDSR 0.07-TP
Dimensions (in mm)

dCl

dCp

Connection

UC

Fault

MISO

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LEM International SA
Route du Nant-d’Avril, 152
1217 Meyrinwww.lem.com

CDSR 0.07-TP
Creepage and Clearance

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LEM International SA
Route du Nant-d’Avril, 152
1217 Meyrinwww.lem.com

CDSR 0.07-TP
Packaging information
Standard delivery in cardboard: L × W × H: 300 × 200 × 200 mm
Each cardboard contains 60 parts, placed into 5 Polystyrene-made trays of 12 parts each one.
Both trays and cardboard are ESD-compliant.
The typical weight of the cardboard is 2.5 Kg.

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LEM reserves the right to carry out modifications on its transducers,in order to improve them.

LEM International SA
Route du Nant-d’Avril, 152
1217 Meyrinwww.lem.com