DATASHEET
ISL78220 FN7688
Rev 4.00
September 2, 2014 6-Phase Interleaved Boost PWM Controller with Light Load Efficiency
Enhancement
The ISL78220 6-phase controller is targeted for applications
where high efficiency (>95%) and high power are required. The
multiphase boost converter architecture uses interleaved
timing to multiply channel ripple frequency and reduce input
and output ripple. Lower ripple results in fewer input/output
capacitors and therefore lower component cost and smaller
implementation area.
The ISL78220 has a dedicated pin to initiate the phase
dropping scheme for higher efficiency at light load by dropping
phases based on the load current, so the switching and core
losses in the converter are reduced significantly. As the load
increases, the dropped phase(s) are added back to
accommodate heavy load transients and improve efficiency.
Input current is sensed continuously by measuring the voltage
across a dedicated current sense resistor or by inductor DCR.
This current sensing provides precision channel-current
balancing, and per-phase overcurrent protection. A separate
totalizing current limit function provides overcurrent protection …