10.1.1 Mixing Supplies

The CDCM6208 incorporates a very flexible power supply architecture. Each building block has its own power supply domain, and can be driven independently with 1.8 V, 2.5 V, or 3.3 V. This is especially of advantage to minimize total system cost by deploying multiple low-cost LDOs instead of one, more-expensive LDO. This also allows mixed IO supply voltages (for example, one CMOS output with 1.8 V, another with 3.3 V) or interfacing to a SPI/I2C controller with 3.3-V supply while other blocks are driven from a lower supply voltage to minimize power consumption. The CDCM6208 current consumption is practically independent of the supply voltage, and therefore a lower supply voltage consumes lower device power. Also note that outputs Y3:0 if used for PECL swing will provide higher output swing if the according output domains are connected to 2.5 V or 3.3 V.