55V Synchronous Buck Controller with Integrated 3A Driver

Product Status: Mass Production


The ISL78268 is a grade 1, automotive, synchronous buck controller with integrated high/low side MOSFET drivers. It supports a wide operating input voltage range of 5V to 55V and up to 60V at VIN when not switching. The integrated driver offers adaptive dead-time control and is capable of supplying up to 2A sourcing and 3A sinking current, allowing the ISL78268 to support power stages designed for a wide range of loads, from under 1A to over 25A.

ISL78268’s fully synchronous architecture enables power conversion with very high efficiency and improved thermal performance over standard buck converters. The ISL78268 also offers diode emulation mode for improved light load efficiency.

While ISL78268 is a peak current mode PWM controller, it also includes a dedicated average output current modulation loop, which achieves constant output current limiting for applications such as battery charging, super-cap charging, and temperature control systems where a constant current must be provided.

The ISL78268 supports switching frequencies from 50kHz to 1.1MHz allowing the user the flexibility to trade-off switching frequency and efficiency against the size of external components.

The ISL78268 offers comprehensive protection features. It includes robust current protection with cycle-by-cycle peak current limiting, average current limiting, and a selectable hiccup or latch-off fault responses. In addition, it offers protection against over-temperature, as well as input and output overvoltages.


  • Wide input range 5V to 55V (switching); withstand 60V (non-switching)
  • Integrated 2A sourcing, 3A sinking MOSFET drivers
  • Constant current regulation/limiting - dedicated average current control loop
  • Adjustable switching frequency or external synchronization from 50kHz up to 1.1MHz
  • Low shutdown current, IQ <1µA
  • Peak current mode control with adjustable slope compensation
  • Selectable diode emulation mode for high efficiency at light load
  • Input and output OVP, cycle-by-cycle current limiting, average current OCP, OTP
  • Selectable hiccup or latch-off fault responses
  • Pb-free 24 Ld 4x4 QFN package (RoHS compliant)
  • AEC-Q100 qualified


 Block Diagram


Basic Information
Production Status
Mass Production
Input Voltage Min (V)
Input Voltage Max (V)
Output Voltage Min (V)
Recommended Output Current Range (A)
VBIAS (min)
4.75 V
VBIAS (max) (V)
IS (min)
.5 µA
IS (typ)
5 mA
Parametric Applications
Automotive Power
Qualification Level
Bias Voltage Range (V)
4.75 to 5.5
Temperature Range
-40 to +125

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