I'm designing my first circuit and I have to use the TEC3-2419 DC-DC converter ([datasheet](https://assets.tracopower.com/20180604154128/TEC3/documents/tec3-datasheet.pdf)) to convert 28V to 9V.

Until not long ago I used to work as a hardware tester where I tested and troubleshooted circuits that use completely different buck converters, such as **[this](http://www.ti.com/lit/ds/symlink/tps54218.pdf)** one.

When I looked at the datasheet for these buck converters, I saw there are one-by-one steps on how to properly design the part of the circuit with the buck. For example, how to choose the right inductor value, choose input/output capacitor, etc...

The datasheet of the TEC3-2419 does not provide those kind of instructions and this leads me to confusion about how to properly design this, which is why I have these questions:

1. Why do I have Vout(+) and Vout(-)? From what I know about buck converters there are multiple switching pins, okay, but why both positive and negative Vout pins?
2. Do I need an inductor at the output? If so, how do I calculate the value?
3. I suppose it would be a good idea to connect bypass capacitors at the input and at the output. How many do I need and what should be their values?
4. Pin #3 is On/off. Does that mean EN pin? If so, should I put a resistor between this pin and the VCC pin (again, something I saw in previous buck converters). What value should the resistor be?
5. What is the difference between single and dual as noted on page 4 of the datasheet? Or, is there a website you can direct me to? I have Googled it but couldn't find any information about this.

Thank you!