ISL6620A

Description

The ISL6620, ISL6620A is a high frequency MOSFET driver designed to drive upper and lower power N-Channel MOSFETs in a synchronous rectified buck converter topology. The advanced PWM protocol of ISL6620, ISL6620A is specifically designed to work with Intersil VR11.1 controllers and combined with N-Channel MOSFETs, form a complete core-voltage regulator solution for advanced microprocessors. When ISL6620, ISL6620A detects a PSI protocol sent by an Intersil VR11.1 controller, it activates Diode Emulation (DE) operation; otherwise, it operates in normal Continuous Conduction Mode (CCM) PWM mode. The IC is biased by a single low voltage supply (5V), minimizing driving losses in high MOSFET gate capacitance and high switching frequency applications. Each driver is capable of driving a 3nF load with less than 10ns rise/fall time. Bootstrapping of the upper gate driver is implemented via an internal low forward drop diode, reducing implementation cost, complexity, and allowing the use of higher performance, cost effective N-Channel MOSFETs. To further enhance light load efficiency, ISL6620, ISL6620A enables diode emulation operation during PSI mode. This allows Discontinuous Conduction Mode (DCM) by detecting when the inductor current reaches zero and subsequently turning off the low side MOSFET to prevent it from sinking current. An advanced adaptive shoot-through protection is integrated to prevent both the upper and lower MOSFETs from conducting simultaneously and to minimize dead time. The ISL6620, ISL6620A has a 20k integrated high-side gate-to-source resistor to prevent self turn-on due to high input bus dV/dt.