Synchronizing the i6A DC-DC Converter Switching Frequencies

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When a number of DC to DC converters are used to power delicate circuitry, enter and output noise may cause system points, significantly when measuring very low sign voltages.  The issue is compounded if the converters’ switching frequencies range with enter voltage or output load. 
Even when the converter’s working frequency is mounted, there can be a tolerance on the switching frequency timing circuit between the converters and only a few Hertz variations between the converters may cause sub-harmonic beat frequencies.

Filtering the inputs and outputs is one resolution, however this may be complicated over a large frequency bandwidth.  If the DC-DC converters had a set switching frequency and may very well be synchronized to collectively or tied to a grasp clock, any board and/or system EMI filtering could be easier.

Though considerably unusual, there are some DC-DC converters which have synchronization functionality.  When the “full feature” option is specified on TDK-Lambda’s low price, mounted frequency, i6A collection of 250W non-isolated DC-DC converters, a number of items can have their working frequency synchronized.

There are 4 methods to attach the modules:

1.      Grasp / Slave, with no section shift.  One i6A module is the “grasp” and the different modules will function at the grasp’s switching frequency.  All the modules draw enter present at the identical time.

 
2.      Grasp / Slave, with 180 diploma section shift.  One i6A module is the “grasp” and different modules will function at the grasp’s switching frequency, however straight out of section.  This may scale back the peak enter ripple present from the provide, requiring much less enter capacitance.  Any module with a jumper between pins 4 and 33 could have the section shift perform activated.

3.      An external clock is used with no section shift.  All the i6A modules function at the identical frequency as the external clock (no grasp / slave). All the modules draw enter present at the identical time.

 
4.      An external clock is used with a 180 levels section shift.  All the i6A modules function at the identical frequency as the external clock (no grasp / slave), however any module with a jumper between pins 4 and 33 could have the section shift perform activated.  This once more reduces the peak enter ripple present from the provide, requiring much less enter capacitance.
 

The i6A non-isolated DC-DC converters are a collection of step down converters (the enter voltage needs to be greater than the output) in the trade customary 1/16th brick footprint.  All fashions feature wide selection enter voltages, as high as 9 to 53V and have wide selection output adjustment from 3.3 – 15V to 3.3 – 40V.  Working efficiencies will be as high as 98%.