Murata Launches a Series of Compact 2 Watt DC/DC Converters

Working off 12 and 15-volt rails, the members of Murata’s MGJ2 series offer +15V/−5V, +15V/−9V, and +20V/−5V bipolar outputs.

Murata’s MGJ2 series. Image courtesy of Murata

The MGJ2 series of DC-DC converters is aimed at powering “high side” and “low side” gate drive circuits for IGBTs/SiC and MOSFETs in bridge circuits. The units feature the high isolation specifications required in bridge circuits used in inverters and motor drives.

 

The Members of the Series

Murata cautions that the units working from a nominal input voltage of 5V are still under development, as are the MGJ2D122005MPC and the MGJ2D152005MPC

 

The members of this new series of converters exhibit a typical isolation capacitance of 3pF, which serves to reduce the transmission of transients across the isolation barrier. This stops EMI from developing due to the circulating currents that might otherwise be generated by high-frequency signals. 

• Ripple and noise across the series range from 45 to 65 microvolts, peak-to-peak (max)
• Efficiencies range from 68 to 73% (minimum)

 

Input Considerations

Input Ranges

• 5 Volt devices: 4.5 to 5.5V, 6V maximum
• 12 Volt devices: 10.8 to 13.2V, 15V maximum
• 15 Volt devices: 13.5 to 16.5V, 18V maximum

All members of the series provide protection for an input short circuit situation

 

Isolation 

As noted by Murata in the series datasheet:

“‘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.”

The members of the MGJ2 series have undergone qualification testing at 5.7kVDC for 1
minute.

Additionally, common-mode transient immunity (CMTI), exceeds 200kV/µs. This enables the converters to deal with high switching frequencies, which range from 80 to 110 kHz across the series.

 

Applications

• Fast EV charging stations
• Solar and wind turbine inverters
• Industrial motor drives
• Uninterruptible power supplies (UPS)

 

Physical Considerations

• The units measure 19.49 × 14.99 × 4.39 mm
• They operate over a 40 to +100°C temperature range, with maximum output power available at temperatures up to 85°C
• Creepage and clearance is 9mm

 

Regulatory and Safety

• UL62368 compliance (for 250VAC reinforced insulation) 
• ANSI/AAMI ES60601-1 certification is pending
• When testing for partial discharge in accordance with IEC 60270, the measured peak inception voltages were better than 2500 volts