What's the difference between current DACs (IDACs) and voltage DACs (VDACs)?

If you are trying to to select a Digital-to-Analog-converter(DAC) you have the choice between a voltage DAC (VDAC) and a current DAC (IDACs).

• Voltage DACs output a voltage that varies with the DAC setting. For example, a voltage DAC might output between 0 and 3.3 Volts.
• Current DACs output a current that varies with the DAC setting. For example, a current DAC might output between 0 and 2 mA

How to select the right type of DAC?

If you have to ask what type of DAC you need, you probably need a voltage DAC. Most DACs nowadays are voltage DACs.

Current DACs are usually used for some types of sensor excitation (see e.g. the ADS1147) where constant current is required, or in more complex analog devices.