The AD5429/AD5439/AD54491 are CMOS， 8-， 10-， and 12-bit， dual-channel， current output digital-to-analog converters （DAC）， respectively. These devices operate from a 2.5 V to 5.5 V power supply， making them suited to battery-powered and other applications. As a result of being manufactured on a CMOS submicron process， these parts offer excellent 4-quadrant multiplication characteristics， with large signal multiplying bandwidths of 10 MHz. The applied external reference input voltage （VREF） determines the full-scale output current. An integrated feedback resistor （RFB） provides temperature tracking and full-scale voltage output when combined with an external current-to-voltage precision amplifier. These DACs use a double-buffered， 3-wire serial interface that is compatible with SPI， QSPI?， MICROWIRE?， and most DSP interface standards. In addition， a serial data out （SDO） pin allows daisy-chaining when multiple packages are used. Data readback allows the user to read the contents of the DAC register via the SDO pin. On power-up， the internal shift register and latches are filled with 0s， and the DAC outputs are at zero scale. The AD5429/AD5439/AD5449 DACs are available in 16-lead TSSOP packages. The EV-AD5415/49SDZ evaluation board is available for evaluating DAC performance. For more information， see the UG-297 evaluation board user guide.