# Current Sensing Transformer, 1:125, 1.28 mH, 5 A, 36 Vµs, 50kHz to 1MHz, 13 ohm
**URL**: https://novapart.co/products/B82801A0135A125/current-sensing-transformer-1125-128-mh-5-a-36-vs
**SKU**: B82801A0135A125
**Manufacturer**: TDK
**Category**: Transformers || Current Sensing Transformers
**Price**: €1.4600
**Stock**: 10+
## Description
Turns Ratio:1:125; DC Resistance:13ohm; Inductance:1.28mH; ET Constant:-; Primary Current:5A; Transformer Mounting:Surface Mount; Product Range:-; SVHC:No SVHC (07-Jul-2017); Depth Max
## Specifications
| Parameter | Value |
|---|---|
| Svhc | No SVHC (15-Jan-2018) |
| Inductance | 1.28mH |
| Et Constant | 36Vµs |
| Turns Ratio | 1:125 |
| Dc Resistance | 13ohm |
| Product Range | B82801A |
| Frequency Range | 50kHz to 1MHz |
| Primary Current | 5A |
| Transformer Mounting | Surface Mount |
| Dc Resistance Primary | 2500µohm |
| Transformer Terminals | J-Bend |
| Dc Resistance Secondary | 13ohm |
## Datasheet
📄 [Download PDF](https://novapart.co/datasheet/farnell:1579325/)
## **SMT current sense transformers**
## EE 4.2 core
**Series/Type: B82801A** Date: **a~í~=pÜÉÉí** December 2012
��EPCOS AG 2012. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS’ prior express consent is prohibited.
## ~~LT~~ **SMT current sense transformers B82801A EE 4.2**
## **Applications**
- Switching power supplies
- Feedback control
- Overload sensing
- Load drop/shut down detection
## **Features**
- Very low DC resistance
- Different turns ratios
- Very small package
- RoHS compatible
## **Marking**
No marking on component
## **Delivery mode and packing units**
- 12 mm blister tape, 178 mm reel
- Carton packaging
- Packing units: 600 pcs./reel;
- 3000 pcs./carton
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
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**SMT current sense transformers**
**B82801A EE 4.2**
## **Dimensional drawing**
**==> picture [71 x 8] intentionally omitted <==**
**----- Start of picture text -----**
Dimensions in mm
**----- End of picture text -----**
## **Application circuit and pinning**
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
**3** 12/12
**SMT current sense transformers**
**B82801A EE 4.2**
## **Technical data and measuring conditions**
|Frequencyrange|50 kHz ... 1 MHz|||
|---|---|---|---|
|Hi-pot|500 V AC, 2 s (windingto winding)|||
|Inductance L (1-2)|100 kHz, 100 mV, @ +25 °C|||
|DC resistance Rmax|Measured at +25 °C|||
|Sensed current|The max. primary current of 7 A causes approx. +40 °C|||
||temperature rise|||
|Solderability|99.9 Sn, lead-free. Or
:|||
||Sn96.5Ag3.0Cu0.5: +(245 5|Sn96.5Ag3.0Cu0.5: +(245 5 °C, (3 0 3) s
+)|°C, (3 0 3) s
+.|
||Wetting of soldering area 95%|Wetting of soldering area 95%||
||(to IEC 60068-2-58)|||
|Resistance to solderingheat|+(260 5) °C, (10|1) s to IEC 60068-2-58||
|Storage conditions|–20 °C … +40 °C,|75% RH||
|Test voltage Vtest|50 Hz, 1 s|||
|Operatingtemperature range|40 °C … +125 °C|||
|Weight|Approx. 0.15g|||
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
**4** 12/12 -
**SMT current sense transformers B82801A** ~~LT~~ **EE 4.2**
> V 8 sense max max = -------------- -----------------------B max n A f s e osc
## **With:**
Bmax Maximum magnetic flux density in the ferrite core of the current sense transformer Vsense,max Maximum output voltage of the measurement signal max Maximum duty cycle ns Number of turns of the secondary winding of the current sense transformer Ae Effective magnetic area of the ferrite core fosc Operating frequency of the switching operator IC Typical value for Ae: 1.44 x 10[-6] m[2] Typical Bmax: 200 mT
V n sense max s = -------------- ---------------- **-** R T I prim max
## **With:**
RT Resistance of burden resistor Vsense,max Maximum output voltage of the measurement signal ns Number of turns on the secondary side of the CT Iprim,max Maximum primary current (peak current)
## **Characteristics and ordering codes**
|Lmin
H|Turns ratio
Np: Ns|DC resistance
Rmax(m )
primary
secondary|DC resistance
Rmax(m )
primary
secondary|Voltage-
time product
V
μs|Recomm.
RT|Ordering code|
|---|---|---|---|---|---|---|
|33|1 : 20
~~a~~
~~ee~~|2.5|320|5.76|20|B82801A0333A020|
|74|1 : 30
~~ee~~|2.5|800|8.6|30|B82801A0743A030|
|132|1 : 40
~~ee~~
~~a~~|2.5
~~ee~~|1300
~~ee~~|11.5
~~ee~~|40
~~ee~~|B82801A0134A040|
|205|1 : 50
~~a~~|2.5
|2200
|14.4
|50
|B82801A0214A050|
|295|1 : 60
~~ee~~|2.5
~~ee~~|3600
~~ee~~|17.3
~~ee~~|60
~~ee~~|B82801A0304A060|
|400|1 : 70
~~a ee~~|2.5
~~ee~~|4600
~~ee~~|20.0
~~ee~~|70
~~ee~~|B82801A0404A070|
|820|1 : 100
~~a~~|2.5
|8700
|28.8
|100
|B82801A0824A100|
|1280|1 : 125
~~ee~~|2.5
~~ee~~|13000
~~ee~~|36.0
~~ee~~|125
~~ee~~|B82801A0135A125|
|1840|1 : 150
~~a~~|2.5|21000|43.2|150|B82801A0185A150|
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
**5** 12/12
## **Recommended reflow soldering curve**
Pb-free solder material (based on JEDEC J-STD 020D)
**==> picture [249 x 135] intentionally omitted <==**
**----- Start of picture text -----**
[t] 3
T4
T3
t 2
T2
T1
[t] 1
**----- End of picture text -----**
IND0814-F
**T1 T2 T3 T4 T1 T2 T3** °C °C °C °C sec sec sec 150 200 217 245 <110 <90 20 ... 40 ~~—————~~ Max. time from +25 °C to T: 300 seconds Max. 3 reflow cycles
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
**6** -
**6** 12/12
## **Taping and packing**
Blister tape
**==> picture [71 x 7] intentionally omitted <==**
**----- Start of picture text -----**
Dimensions in mm
**----- End of picture text -----**
## Reel
**==> picture [71 x 7] intentionally omitted <==**
**----- Start of picture text -----**
Dimensions in mm
**----- End of picture text -----**
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
**7** 12/12
## ~~LT~~ **Cautions and warnings**
- Please note the recommendations in our Inductors data book (latest edition) and in the data sheets.
- Particular attention should be paid to the derating curves given there. Derating must be applied in case the ambient temperature in the application exceeds the rated temperature of the component.
- Ensure the operation temperature (which is the sum of the ambient temperature and the temperature rise caused by losses / self-heating) of the component in the application does not exceed the maximum value specified in the climatic category.
- The soldering conditions should also be observed. Temperatures quoted in relation to wave soldering refer to the pin, not the housing.
- If the components are to be washed varnished it is necessary to check whether the washing varnish agent that is used has a negative effect on the wire insulation, any plastics that are used, or on glued joints. In particular, it is possible for washing varnish agent residues to have a negative effect in the long-term on wire insulation.
- Washing processes may damage the product due to the possible static or cyclic mechanical loads (e.g. ultrasonic cleaning). They may cause cracks to develop on the product and its parts, which might lead to reduced reliability or lifetime.
- The following points must be observed if the components are potted in customer applications: – Many potting materials shrink as they harden. They therefore exert a pressure on the plastic housing or core. This pressure can have a deleterious effect on electrical properties, and in extreme cases can damage the core or plastic housing mechanically.
- It is necessary to check whether the potting material used attacks or destroys the wire insulation, plastics or glue.
- The effect of the potting material can change the high-frequency behaviour of the components.
- Ferrites are sensitive to direct impact. This can cause the core material to flake, or lead to breakage of the core.
- Even for customer-specific products, conclusive validation of the component in the circuit can only be carried out by the customer.
Please read _Cautions and warnings_ and _Important notes_ at the end of this document.
**8** 12/12 -
~~LT~~ **Important notes**
The following applies to all products named in this publication:
1. Some parts of this publication contain **statements about the suitability of our products for certain areas of application** . These statements are based on our knowledge of typical requirements that are often placed on our products in the areas of application concerned. We nevertheless expressly point out **that such statements cannot be regarded as binding statements about the suitability of our products for a particular customer application.** As a rule, EPCOS is either unfamiliar with individual customer applications or less familiar with them than the customers themselves. For these reasons, it is always ultimately incumbent on the customer to check and decide whether an EPCOS product with the properties described in the product specification is suitable for use in a particular customer application.
2. We also point out that **in individual cases, a malfunction of electronic components or failure before the end of their usual service life cannot be completely ruled out in the current state of the art, even if they are operated as specified.** In customer applications requiring a very high level of operational safety and especially in customer applications in which the malfunction or failure of an electronic component could endanger human life or health (e.g. in accident prevention or life-saving systems), it must therefore be ensured by means of suitable design of the customer application or other action taken by the customer (e.g. installation of protective circuitry or redundancy) that no injury or damage is sustained by third parties in the event of malfunction or failure of an electronic component.
3. **The warnings, cautions and product-specific notes must be observed** .
4. In order to satisfy certain technical requirements, **some of the products described in this publication may contain substances subject to restrictions in certain jurisdictions (e.g. because they are classed as hazardous)** . Useful information on this will be found in our Material Data Sheets on the Internet (www.epcos.com/material). Should you have any more detailed questions, please contact our sales offices.
5. We constantly strive to improve our products. Consequently, **the products described in this publication may change from time to time** . The same is true of the corresponding product specifications. Please check therefore to what extent product descriptions and specifications contained in this publication are still applicable before or when you place an order.
We also **reserve the right to discontinue production and delivery of products** . Consequently, we cannot guarantee that all products named in this publication will always be available. The aforementioned does not apply in the case of individual agreements deviating from the foregoing for customer-specific products.
6. Unless otherwise agreed in individual contracts, **all orders are subject to the current version of the “General Terms of Delivery for Products and Services in the Electrical Industry” published by the German Electrical and Electronics Industry Association (ZVEI)** .
7. The trade names EPCOS, BAOKE, Alu-X, CeraDiode, CeraLink, CSMP, CSSP, CTVS, DeltaCap, DigiSiMic, DSSP, FilterCap, FormFit, MiniBlue, MiniCell, MKD, MKK, MLSC, MotorCap, PCC, PhaseCap, PhaseCube, PhaseMod, PhiCap, SIFERRIT, SIFI, SIKOREL, SilverCap, SIMDAD, SiMic, SIMID, SineFormer, SIOV, SIP5D, SIP5K, ThermoFuse, WindCap are **trademarks registered or pending** in Europe and in other countries. Further information will be found on the Internet at www.epcos.com/trademarks.
**9** -
**9** 12/12
## Links
- [View this product on Novapart](https://novapart.co/products/B82801A0135A125/current-sensing-transformer-1125-128-mh-5-a-36-vs)
- [Request a quote for this part](https://novapart.co/quote/)
- [Supplier page](https://es.farnell.com/epcos/b82801a0135a125/transformer-current-e4-2-1280uh/dp/1579325)
---
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