Si533xx Current Consumption vs Frequency

by <a href="http://community.silabs.com/t5/Welcome-and-Announcements/Community-Ranking-System-and-Recognition-Program/m-p/140490#U140490"><font color="#000000"><font size="2">Hero Employee</font></font> </a> FranBoudreau on ‎11-06-2014 02:53 PM

Question

The Si533xx data sheet shows current consumption at a given frequency, what is it at other frequencies?

Answer

Answer

The IDDOA and IDDOB current consumption is consistent over the operating range of output frequencies for the differential outputs; LVPECL, LPPECL, LVDS, HCSL and CML. The current listed in the data sheet should be used for any valid frequency.

 

IDDOA/B current consumption does depend on frequency for CMOS output operation, below shows how IDDOx current changes with frequency.

IDDOvsFreq_CMOS.PNG

The legends show the Output logic, drive strength and supply voltage. As an example CMOS-24-3.3V is a CMOS output, 24mA drive and 3.3V operation. The drive current is per output.

 

The IDD current has minimal change vs frequency as follows