The TPS4009x family of multiphase synchronous buck controllers from Texas Instruments implements stepdown power converters that deliver 40 to 120 A. The controllers also use TI's technique for single-cycle current balancing, which is accurate to within 5%.
Housed in 24-pin TSSOPs, these programmable pulse-width-modulation controllers manage two, three, or four phases, with each phase switching at up to 1 MHz. They provide cycle-by-cycle current sharing in output phases over the load range. Other features include current-sense fault protection, programmable overcurrent protection, and individual phase-current detection. Gate drivers aren't included on-chip.
Pricing is $1.79 each per 1000.