ISL78225

• Product introduction

Key features

Adjustable slope compensation for peak current mode PWM control
Precision resistor/DCR current sensing
2, 3 or 4 phase operation
Adjustable phase drop/diode simulation/pulse skipping high efficiency at light loads
Adjustable switching frequency or external synchronization of 1MHz per phase to 75kHz
Over-temperature/Overvoltage protection
2V± 1.0% internal reference
Pb-free 44-pin 10X10 EP-TQFP (RoHS compliant)
-40°C to +125°C operating temperature range
AEC-Q100 certified
The provisions of TS16949
description

The ISL78225 4-phase controller is designed for applications that require high efficiency (> 95%) and high power. The multiphase boost converter architecture uses interleaved time multiplied by channel ripple frequency and reduced input and output ripple. Fewer input/output capacitors, thus reducing component cost and implementing the result of low ripple with a smaller implementation area. The ISL78225 has a dedicated pin to start the falling phase, higher efficiency at light loads, based on the load current drop phase planning, so that the switching and core losses in the converter are significantly reduced. As the load increases, the falling stage (S) is added back to accommodate heavy load transients and improve work efficiency. Input current sensing is carried out by measuring voltage continuously through a dedicated current sense resistor or inductor DCR. This current sensing provides accurate channel current balancing with per-phase overcurrent protection. A single accumulation current limit function provides overcurrent protection for all combined phases. These two stages of current protection provide the highest performance and circuit reliability. The ISL78225 can also provide input voltage tracking via the VREF2 pin. Compare the reference voltage to the VREF2 pin or the internal reference 2V low. Through a resistor network between VIN and VREF2 pins, the output voltage tracks the input voltage limiting the output power under automotive starting conditions. The ISL78225 can output clock signals for scaling operations in 8 stages, which provides high system flexibility. The threshold sensitive enable input can accurately coordinate the ISL78225 startup with any other voltage rail.