Renesas Electronics Corporation
Conv DC-DC Single-OUT Step Up/Step Down 3V to 36V 20-Pin QFN
2.5A Regulator with Integrated High-Side MOSFET for Synchronous Buck or Boost Buck Converter
The ISL85403 is a 40V, 2. 5A synchronous buck or boost-buck controller with an integrated high-side MOSFET and low-side driver. In Buck mode, the ISL85403 supports a wide input range of 3V to 40V. In Boost-Buck mode, the input range can be extended down to 2. 5V and output regulation can be maintained when VIN drops below VOUT, enabling sensitive electronics to remain on in low input voltage conditions. The ISL85403 has a flexible selection of Forced PWM mode and PFM mode. In PFM mode, the quiescent input current is as low as 180µA (AUXVCC connected to VOUT). The load boundary between PFM and PWM can be programmed to cover wide applications. The low-side driver can either be used to drive an external low-side MOSFET for a synchronous buck or left unused for a standard non-synchronous buck. The low-side driver can also be used to drive a boost converter as a preregulator followed by a buck controlled by the same IC, which greatly expands the operating input voltage range down to 2. 5V or lower. ISL85403 offers robust current protection. It uses peak current mode control with cycle-by-cycle current limiting. It is implemented with frequency foldback under current limit condition; also, the hiccup overcurrent mode ensures reliable operations under harsh short conditions. The ISL85403 has comprehensive protections against various faults including overvoltage and over-temperature protection.
Features:
Buck mode: input voltage range 3V to 40V
Boost mode expands operating input voltage lower than 2.5V
Selectable Forced PWM mode or PFM mode
300µA IC quiescent current (PFM, no load); 180µA input quiescent current (PFM, no load, VOUT tied to AUXVCC)
Less than 5µA (MAX) shutdown input current (IC disabled)
Operational topologies
Synchronous buck
Non-synchronous buck
Two-stage boost buck
Non-inverting single inductor buck boost
Programmable frequency from 200kHz to 2.2MHz and frequency synchronization capability
±1% tight voltage regulation accuracy
Reliable overcurrent protection
Temperature compensated current sense
Cycle-by-cycle current limiting with frequency foldback
Hiccup mode for worst case short condition
20 Ld 4x4 QFN package
Pb-free (RoHS compliant)
Applications:
General purpose
24V bus power
Battery power
Point of load
Embedded processor and I/O supplies
Robotic Vacuum
Smart Coffee Machine
Emergency Broadcast System (Watercraft)
Smart Grid Fault Indicator Unit
Electronic Drug Delivery System
Cloud Gateway Module
Drug Delivery with ISO 12207 Software
Power Solution for Smart Power Meter with 4G Module
Master Actuator for Automatic Home or Building HVAC System
Low Power Backup with Supercapacitor
Alexa Controlled Soundbar
Connected Oxygen Concentrator Controller
Embedded Programmable Logic Controller (PLC) for Industrial Use
Solar Panel Tracker and Cleaning System