H-XS-1W&G-XS-1W Series
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.
Professional Power Module H_S-1W&G_S-1W series of DC/DC converters are all 100% production tested at their stated isolation voltage. This is 6KVDC for 1 second.
A question commonly asked is,"What is the continuous voltage that can be applied across the part in normal operation?"
The H_S-1W&G_S-1W series has been recognized by Underwriters Laboratory to 300Vrms for Supplementary Insulation and 150Vrms for Reinforced Insulation.
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.
OUTPUT RIPPLE REDUCTION
By using the values of inductance and capacitance stated, the output ripple at the rated load is lowered to 5mV p-p max.
Component selection
Capacitor: Ceramic chip capacitors are recommended. It is required that the ESR(Equivalent Series Resistance)should be as low as possible.X7R types are recommended.
The voltage rating should be at least twice(except for 15V output),the rated output voltage of the DC/DC converter.
Inductor: The rated current of the inductor should not be less than of the output of the DC/DC converter. At the rated current, the DC resistance of the inductor should be
such that the voltage drop across the inductor is <2% of the rated voltage of the DC/DC converter. The SRF(Self Resonant Frequency) should be >20MHz.
Single output types
Dual output types
OUTPUT RIPPLE REDUCTION
Ripple & Noise Characterisation Method
Ripple and noise measurements are performed with the following test configuration.
C1
C2
C3
R1
1uF X7R multilayer ceramic capacitor, voltage rating to be a minimum of 3 times the output voltage of the DC/DC converter
10uF tantalum capacitor, voltage rating to be a minimum of 1.5 times the output voltage of the DC/DC converter
100nF multilayer ceramic capacitor, general purpose
450Ω resistor, carbon film,±1% tolerance
R2
T1
50Ω BNC termination
3T of the caox 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
R3
50Ω resistor, carbon film,±1%
Measured values are multiplied by 10 to obtain the specified values.
Differential Mode Noise Test Schematic
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