+ Interleaving provides partial
ripple cancellation with exact cancellation (in theory at least) occurring at
N+1 points in duty cycle (from 0 to 100 percent) where N is the number of
evenly interleaved phases.
+ Interleaving provides N times frequency multiplication of composite ripple currents (this usually reduces the EMI suppression task).
- Interleaving requires N separate sets of drive and (some) control circuitry.
- Interleaving requires phase control. Although this can be as simple as phased digital clock pulses, more sophisticated control will be required to provide advanced features; for example, fast full current pulse capability via transient simultaneous synchronization, or to provide phase locking while allowing the operating frequency to vary in response to line and load variations, etc.
- Interleaving may require special protection circuitry to guard against excessive long term ripple current in the event that all or most of the phases inadvertently lock up (even though power stage operation remains otherwise completely normal). This is a potential fault that is unique to systems with interleaved phases.