Isolated DC-DC Power Converter

Full Regulation and Isolation

Isolated DC-DC converters provide no electrical contact between input and output circuits. Isolated DC-DC converters are integrated into a broad range of applications, including power metering, industrial programmable logic controllers (PLCs), insulated-gate bipolar transistor (IGBT) driver power supplies, and industrial automation. These converters often are used to provide galvanic isolation and enhance noise immunity. Moreover, they can be used to generate multiple output voltage rails, including dual-polarity rails. In terms of output voltage regulation accuracy, the isolated DC-DC converters provide a regulated DC output.

Dimensions and Pinout

Input and Output Capacitor Selection

In circuits that are sensitive to noise and ripple, a filtering capacitor may be added to the input and output to reduce the noise and ripple. The capacitance of the output filter capacitor must be properly matched based on input and output voltages. If the capacitance is too big, a startup problem might arise. Based on your input and output voltages, choose an appropriate filter capacitor from the reference list.

Input Voltage:

• 3.3v DC use a 4.7uF Capacitor at Cin
• 5v DC use a 4.7uF Capacitor at Cin
• 12v DC use a 2.2uF Capacitor at Cin

Output Voltage:

• 3.3v DC use a 10uF Capacitor at Cout
• 5v DC use a 10uF Capacitor at Cout
• 9v DC use a 4.7uF Capacitor at Cout
• 12v DC use a 2.2uF Capacitor at Cout
• 15v DC use a 1uF Capacitor at Cout

Minimum and Maximum Current Limits

The Isolated Power Module has both maximum and minimum current specifications. The minimum current requirement ensures the module can operate efficiently and reliably.

The minimum load specification across the output must not be less than 10% of the maximum full load specification. It is imperative not to allow the module to operate with no load. If the actual current requirements are very low, connect a resistor with proper resistance across the output to increase the load.

Overload Protection

Under normal operating conditions, the output side of the module has no protection against over-current or short-circuits. The simplest method to protect from over-current is with a self-recovery fuse in series at the input.