MGJ6 Low Profile Series
5.7kVDC Isolated 6W Gate Drive SM DC/DC Converters
KDC_MGJ6C-LP.B01 Page 6 of 11
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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.
Murata Power Solutions MGJ6 series of DC/DC converters are all 100% production tested at 5.7kVDC for 1 second and have been qualification tested at 5.7kVDC for 1 minute.
A question commonly asked is, “What is the continuous voltage that can be applied across the part in normal operation?”
When the insulation in the MGJ6 series is not used as a safety barrier , i.e. provides functional isolation only, continuous or switched voltages across the barrier up to
3kV are sustainable. Long term reliability testing at these voltages continues. Peak Inception voltages measured were in excess of 3.5kV when testing for partial dis-
charge in accordance with IEC 60270. Please contact Murata for further information.
The MGJ6 series has been recognised by Underwiters Laboratory to 250 Vrms Reinforced Insulation, please see safety approval section below.
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. We therefore strongly advise against repeated high voltage isolation testing, but if it is absolutely required, that the voltage be
reduced by 20% from specified test voltage.
SAFETY APPROVAL
ANSI/AAMI ES60601-1
The MGJ6 series is pending recognition ANSI/AAMI ES60601-1 and provides 2 MOPP (Means Of Patient Protection) based upon a working voltage of 250 Vrms max., between
Primary and Secondary.
UL 60950
The MGJ6 series has been recognised by Underwriters Laboratory (UL) to UL 60950 for reinforced insulation to a working voltage of 250Vrms with a maximum measured product
operating temperature of 130°C.
Creepage and clearance 8mm.
FUSING
The MGJ6 series of converters are not internally fused so to meet the requirements of UL an anti-surge input line fuse should always be used with ratings as defined below.
Input Voltage, 5V 4A
Input Voltage, 12V 2A
Input Voltage, 24V 1A
All fuses should be UL recognized, 125V rated.
CHARACTERISATION TEST METHODS
Ripple & Noise Characterisation Method
Ripple and noise measurements are performed with the following test configuration.
C1 1µF X7R m ultilayer ceramic capacitor, voltage rating to be a minimum of 3 times the output voltage of the DC/DC converter
C2
10µF tantalum capacitor, voltage rating to be a minimum of 1.5 times the output voltage of the DC/DC converter with an ESR of less
than 100m at 100 kHz
C3 100nF multilayer ceramic capacitor, general purpose
R1 450 resistor, carbon film, ±1% tolerance
R2 50 BNC termination
T1 3T of the coax cable through a ferrite toroid
RLOAD Resistive load to the maximum power rating of the DC/DC converter. Connections should be made via twisted wires
Measured values are multiplied by 10 to obtain the specified values.
Differential Mode Noise Test Schematic
OSCILLOSCOPE
Y INPUT
SUPPLY
C1 C2 C3 R1 T1
R2
Input Output
DC/DC Converter
R LOAD
+
+
-
-
