Clock solution providing in phase and 90 / 180 degrees out of phase outputs?

LMK04906 (to be released in May 2012) is a lower-cost version of the LMK04806 (released) with fewer outputs and can provide 2 to 12 multi-phase CMOS/TTL outputs at 300 kHz for synchronizing multiple switchers.  Any unused outputs / features may be shut-down to reduce power.  Note that this device was not designed specifically for this application and may be overkill in terms of performance/power/size, but does provide a lot of flexibility/programmability if this is important for system performance optimization.

LMK04906 Example Use Case for Generating Multiphase SYNC Outputs at 300 kHz

• Use single-loop PLL2 mode with a low-cost 10 MHz crystal to lock the on-chip VCO to 2.4 GHz (yes, Giga).  The 2.4 GHz VCO can be divided to 300 MHz (distribution bus frequency) using VCO divider=8 and ultimately 300 kHz (output frequency) using output divider=1000. 
• Programmable output drivers allows you to independently configure each output as 3.3 V CMOS with normal or inverted phase (0 or 180 degrees).  To achieve phases between 0 degrees to +/-180 degrees (or slightly beyond), use the programmable digital delay (per channel) and sync features to adjust the delay range from 0 us to 1.723 us (i.e. >180 degrees offset at 300 kHz) with delay step size of 3.333 ns (1 period of 300 MHz bus frequency) or 0.36 degrees/step. 

LMK04906 operates over the industrial temp range and uses a Microwire programming interface (subset of SPI).  Note that minimum VCO tuning range of this device (2.37 GHz) limits the lowest output frequency to 284 kHz (= 2.37 GHz / VCO_DIV / CLKout_DIV, where VCO_DIV=8 (max) and CLKout_DIV=1045 (max) ).

Best regards,

Alan