78253/55MVC-R - Murata Power Solutions

KMP_78253C_D06 Page 1 of 5

78253 Series

MAX253 Compatible Converter Transformers

www.murata-ps.com

www.murata-ps.com/support

For full details go to

www.murata-ps.com/rohs

FEATURES

 RoHS compliant

Maxim MAX253 compatible

3.3V and 5V versions

Isolation to 4kVDC

Frequency range to 500kHZ

Toroidal construction

Industry-standard pinout

UL 94 V-0 package materials

Fully encapsulated

Low proﬁle

Surface mount option

Industrial temperature range

DESCRIPTION

The 78253 series of converter transformers are

speciﬁcally designed for use with the MAX253

chip set to provide isolated power supplies. The

5V version can supply 1W and the 3.3V version

can supply 500mW. A centre tapped secondary

winding allows for full bridge, half bridge or

voltage doubling.

Surface-mount parts

The surface-mount (M sufﬁx) products are not

recommended for new designs. For existing designs,

however, Murata Power Solutions will continue to

manufacture and fully support these parts.

For recommended alternatives please refer to the

78253J Series datasheet.

SELECTION GUIDE

Order Code Input Voltage Output

Voltage

Max. Output

Current

Isolation

Voltage Turns

Ratio

Package

Style

V V mA VDC

78253/35C 3.3 5.0 100 1500 1:2.27 DIL

78253/35MC SM

78253/55C 5.0 5.0 200 1500 1:1.31 DIL

78253/55MC SM

78253/35VC 3.3 5.0 100 4000 1:2.14 DIL

78253/35MVC SM

78253/55VC 5.0 5.0 200 4000 1:1.33 DIL

78253/55MVC SM

ORDER CODE DETAILS

Order Code Package Type Packaging Type Quantity

78253/XX(V)C 6 Pin DIL Tube 50

78253/XXM(V)C 6 Pin SM Tube 50

78253/XXM(V)C-R 6 Pin SM Tape & Reel 500

78253/35(M)C CHARACTERISTICS

Parameter Conditions Min. Typ. Max. Units

Primary Inductance, LP100kHz, 250mV 0.30 0.38 0.46 mH

Secondary Inductance, LS100kHz, 250mV 1.60 2.00 2.40 mH

Leakage Inductance, LL100kHz, 250mV 0.30 1.00 μH

Interwinding Capacitance, CWW 100kHz, 250mV 30 50 pF

Primary D.C. Resistance, RDC >0.1VDC 0.40 1.00 Ω

Volt-time Product, Et Pins 1/2 or 2/3 30 35 Vμs

78253/55(M)C CHARACTERISTICS

Parameter Conditions Min. Typ. Max. Units

Primary Inductance, LP100kHz, 250mV 0.60 0.83 1.10 mH

Secondary Inductance, LS100kHz, 250mV 1.10 1.40 1.70 mH

Leakage Inductance, LL100kHz, 250mV 0.35 1.00 μH

Interwinding Capacitance, CWW 100kHz, 250mV 30 50 pF

Primary D.C. Resistance, RDC >0.1VDC 0.70 1.50 Ω

Volt-time Product, Et Pins 1/2 or 2/3 40 50 Vμs

78253/35(M)VC CHARACTERISTICS

Parameter Conditions Min. Typ. Max. Units

Primary Inductance, LP100kHz, 20mV 110 142 185 μH

Secondary Inductance, LS100kHz, 20mV 550 710 850 μH

Leakage Inductance, LL100kHz, 250mV 3.00 5.00 μH

Interwinding Capacitance, CWW 100kHz, 250mV 4.20 8.00 pF

Primary D.C. Resistance, RDC >0.1VDC 0.30 0.50 Ω

Volt-time Product, Et Pins 1/2 or 2/3 18 22 Vμs

78253/55(M)VC CHARACTERISTICS

Parameter Conditions Min. Typ. Max. Units

Primary Inductance, LP100kHz, 20mV 190 240 310 μH

Secondary Inductance, LS100kHz, 20mV 350 444 540 μH

Leakage Inductance, LL100kHz, 250mV 5.20 8.00 μH

Interwinding Capacitance, CWW 100kHz, 250mV 4.20 8.00 pF

Primary D.C. Resistance, RDC >0.1VDC 0.40 0.60 Ω

Volt-time Product, Et Pins 1/2 or 2/3 25 28 Vμs

All speciﬁcations typical at TA=25°C

KMP_78253C_D06 Page 2 of 5

78253 Series

MAX253 Compatible Converter Transformers

www.murata-ps.com/support

PACKAGE SPECIFICATIONS

MECHANICAL DIMENSIONS

RECOMMENDED FOOTPRINT DETAILS

6 Pin DIL 6 Pin SM

ABSOLUTE MAXIMUM RATINGS

Operating free air temperature range -40°C to 85°C

Storage temperature range -50°C to 125°C

Lead Temperature 1.5mm from case for 10 seconds 300°C

Peak current IPK 400mA

Isolation voltage 78253/XX(M)C (ﬂash tested for 1 second) 1500VDC

Isolation voltage 78253/XX(M)VC (ﬂash tested for 1 second) 4000VDC

0.135±0.02

(3.44±0.50)

0.25

(6.35)

0.354

(9.0) MAX

0.375

(9.52) MAX

0.012(0.30)

0.008(0.20) 0.40

(10.16) 0.1 (2.54)

0.025 (0.63)

0.021 (0.53)

0.354

(9.0) MAX

0.375

(9.52) MAX

0.5

(12.70)

0.025 (0.63)

0.021 (0.53)

0.1

(2.54)

0.035

(0.90)

0.012 0.30

(0.008 0.20)

0.25

(6.35)

78253/55MC

XYYWW

78253/35C

XYYWW

Primary Secondary

0.10 (2.54)

Ø0.05 (1.20)+0.006 (0.15)

-0.000 (0.00)

6 Pin DIL 6 Pin SM

Unless otherwise stated all dimensions in inches (mm) ±0.01 (0.25).

All pins on a 0.1 (2.54) pitch and within ±0.01 (0.25) of true position.

Package weight 1.0g Typ.

0.45

(11.50)

0.10 (2.54)

0.04

(1.00)

0.06 (1.60)

Unless otherwise stated all dimensions in inches (mm) ±0.01 (0.25).

All pins on a 0.1 (2.54) pitch and within ±0.01 (0.25) of true position.

Top ViewTop View

KMP_78253C_D06 Page 3 of 5

78253 Series

MAX253 Compatible Converter Transformers

www.murata-ps.com/support

TYPICAL CHARACTERISTICS (VOLTAGE CURVES)

VOLTAGE CURVES

Output Voltage (V)

Output Current (mA) Output Current (mA)

Output Voltage (V)

Output Current (mA) Output Current (mA)

EFFICIENCY CURVES

Efﬁciency (%)

Output Current (mA) Output Current (mA)

Efﬁciency (%)

Output Current (mA) Output Current (mA)

All curves are derived from testing with the Maxim MAX235 IC using the circuit shown in application note MPAN-03 ( download at http://www.murata-ps.com/data/apnotes/mpan-03.pdf).

020 40 60 80 100 120

78253/35(M)C

400

78253/55(M)C

0100 200 300

78253/35(M)VC

020 40 60 100

78253/55(M)VC

0100 200 300 400

78253/35(M)C

100

020 40 60 120

80 100

78253/55(M)C

100

00200 400

300

100

78253/35(M)VC

020 40 60 100

100

78253/55(M)VC

100

00200 400

300

100

KMP_78253C_D06 Page 4 of 5

78253 Series

MAX253 Compatible Converter Transformers

www.murata-ps.com/support

TYPICAL CHARACTERISTICS (VOLTAGE CURVES) continued

VOLTAGE DEVIATION

Voltage Deviation from Nominal

25°C Output (%)

Voltage Deviation from Nominal

25°C Output (%)

Temperature (°C) Temperature (°C)

Voltage Deviation from Nominal

25°C Output (%)

Voltage Deviation from Nominal

25°C Output (%)

Temperature (°C) Temperature (°C)

78253/35(M)C

110

105

100

-50 050

-25 75 100

78253/55(M)C

110

105

100

-50 050

-25 75 100

78253/35(M)VC

110

105

100

-50 050

-25 75 100

78253/55(M)VC

110

105

100

-50 050

-25 75 100

SOLDERING INFORMATION1

Pin ﬁnish Matte tin

Peak wave solder temperature 300˚C for 10 seconds

Peak reﬂow temperature 220˚C2

TUBE OUTLINE DIMENSIONS

All speciﬁcations typical at TA=25°C

1 For further information, please visit www.murata-ps.com/rohs

2 For high temperature reﬂow parts see 78253J series.

0.023±0.005

(0.60±0.15)

0.16 (4.00)

0.22 (5.50)

0.43

(10.95)

0.51

(12.95)

0.15

(3.80)

0.62 (15.70)

Tube length: 18.3±0.08 (465±2). Tube quantity: 50.

Tube material: Antistatic coated clear pvc.

Unless otherwise stated all dimensions in inches(mm) ±0.01 (0.25).

TECHNICAL NOTES

ISOLATION VOLTAGE

‘Hi Pot Test’, ‘Flash Tested’, ‘Withstand Volt-

age’, ‘Proof Voltage’, ‘Dielectric Withstand

Voltage’ & ‘Isolation Test Voltage’ are all terms

that relate to the same thing, a test voltage,

applied for a speciﬁed time, across a compo-

nent designed to provide electrical isolation, to

verify the integrity of that isolation.

All products in this series are 100% production

tested at their stated isolation voltage.

A question commonly asked is, “What is the

continuous voltage that can be applied across

the part in normal operation?”

For a part holding no speciﬁc agency approv-

als both input and output should normally be

maintained within SELV limits i.e. less than

42.4V peak, or 60VDC. The isolation test

voltage represents a measure of immunity to

transient voltages and the part should never

be used as an element of a safety isolation

system. The part could be expected to function

correctly with several hundred volts offset

applied continuously across the isolation bar-

rier; but then the circuitry on both sides of the

barrier must be regarded as operating at an

unsafe voltage and further isolation/insulation

systems must form a barrier between these

circuits and any user-accessible circuitry ac-

cording to safety standard requirements.

REPEATED HIGH-VOLTAGE

ISOLATION TESTING

It is well known that repeated high-voltage

isolation testing of a barrier component can

actually degrade isolation capability, to a

lesser or greater degree depending on ma-

terials, construction and environment. This

series has toroidal isolation transformers,

with no additional insulation between pri-

mary and secondary windings of enameled

wire. While parts can be expected to with-

stand several times the stated test voltage,

the isolation capability does depend on the

wire insulation. Any material, including this

enamel (typically polyurethane) is suscep-

tible to eventual chemical degradation when

subject to very high applied voltages thus

implying that the number of tests should be

strictly limited. We therefore strongly advise

against repeated high voltage isolation test-

ing, but if it is absolutely required, that the

voltage be reduced by 20% from speciﬁed

test voltage.

This consideration equally applies to agency

recognised parts rated for better than

functional isolation where the wire enamel

insulation is always supplemented by a

further insulation system of physical spacing

or barriers.

KMP_78253C_D06 Page 5 of 5

78253 Series

MAX253 Compatible Converter Transformers

www.murata-ps.com/support

Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other

technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply

the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Speciﬁcations are subject to change without

This product is subject to the following operating requirements

and the Life and Safety Critical Application Sales Policy:

Refer to: http://www.murata-ps.com/requirements/

TAPE & REEL SPECIFICATIONS

REEL OUTLINE DIMENSIONS

TAPE OUTLINE DIMENSIONS

1.20

(30.4) Max.

0.94-1.08 (23.9-27.4)

0.53 (13.50)

0.50 (12.80)

0.059 (1.50)

Min.

2.36 (60) Min.

0.80 (20.20) Min.

3.9 (100)

Min.

Leader section

15.7 (400) Min.

Goods

enclosure

section

Trailer section

6.3 (160) Min.

Ø15.039 (382) Max.

0.96 (24.4)

1.04 (26.4)

Reel quantity: 500

Unless otherwise stated all

dimensions in inches (mm) ±0.01(0.25).

* Includes ﬂange distortion at outer edge.

g Measured at hub.

0.024 (0.60) Max.

0.283 (7.20)

0.369 (9.37)

Direction of unreeling

0.069 (1.75)

0.453 (11.50)

0.157 (4.00) 0.079 (2.00)

0.472 (12.00)

Cover tape

0.059 (1.50 )

+0.004

-0.000 +0.10

-0.00

0.945 (24.00 )

+0.012

-0.004

+0.30

-0.10

78253

35MC

XYYWW

Unless otherwise stated all

dimensions in inches (mm) ±0.01(0.25).

Mouser Electronics

Authorized Distributor

Click to View Pricing, Inventory, Delivery & Lifecycle Information:

Murata:

78253/55 78253/35MV 78253/35M 78253/35V 78253/55M 78253/35 78253/55MV 78253/55V 78253/55MVC

78253/35VC 78253/35MC 78253/35MVC 78253/55VC 78253/55MC 78253/35C 78253/55C 78253/35MC-R

78253/35MVC-R 78253/55MC-R 78253/55MVC-R