782100 Series

PE22100 Compatible Converter Transformers

KMP_782100_C01 Page 2 of 5

www.murata.com

ABSOLUTE MAXIMUM RATINGS

Operating free air temperature range

-40°C to 85°C

Storage temperature range

-50°C to 125°C

TECHNICAL NOTES

ISOLATION

VOLTAGE

‘Hi Pot Test’, ‘Flash Tested’, ‘Withstand Voltage’, ‘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 component 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 approvals 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 barrier; 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 according 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

materials, construction and environment. This series has toroidal isolation transformers,

with no additional insulation between primary and secondary windings of enamelled

wire. While parts can be expected to withstand several times the stated test voltage,

the isolation capability does depend on the wire insulation. Any material, including this

enamel (typically polyurethane) is susceptible 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

testing, but if it is absolutely required, that the voltage be reduced by 20% from speci-

fied 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.

3. Representative samples of the product were subjected to the conditioning described in IPC/JEDEC J-STD-020D and passed electrical testing, package coplanarity and visual inspection which revealed no

external cracks or changes in package body flatness.

JVC VARIANTS SOLDERING INFORMATION

Pin finish

Matte tin

Max. peak reflow temperature

245°C

Moisture sensitivity level3

1

Max. time above liquidous (217

°C)

100s

VC VARIANTS SOLDERING INFORMATION

Pin finish

Matte tin

Peak wave solder temperature

260°C for 10 seconds