Renesas ISL81601 - Buck-Boost Controller

It provides cycle-by-cycle current limit in both directions while in buck or boost mode, and generates point-of-load (POL) and voltage rail conversions with peak efficiency up to 99%. The controller uses a proprietary buck-boost algorithm that allows inherent peak current sensing for a robust design and produces the smoothest mode transitions between buck, boost and buck-boost. Its proprietary algorithm reduces low frequency ripple at Vout, ensuring minimal disturbances during line or load transients. The algorithm also ensures predictable ripple voltage under all conditions.

The ISL81601 features multilayer overcurrent protection (OCP) that helps designers to design a charging/discharging circuit that ensures constant current operation for safe and reliable battery power applications. It is available in 32LD 5mmx5mm QFN package and provides full protection features such OVP, UVP, OTP and OCP. ISL81601 is a 4.5Vin~ 60V_in device and the ISL81401 is a 4.5Vin~40V_in device.

The ISL81401A is a low cost unidirectional version of the ISL81401.
 

Key features

• Single inductor 4-switch buck-boost controller
• On-the-fly bidirectional operation with independent control of voltage and current on both ends
• Proprietary algorithm for smoothest mode transition MOSFET drivers with adaptive shoot-through protection
• Wide input voltage range: 4.5V to 60V
• Wide output voltage range: 0.8V to 60V
• Supports pre-biased output with SR soft-start
• Programmable frequency: 100kHz to 600kHz
• Supports parallel operation current sharing with cascade phase interleaving
• External sync with clock out or frequency dithering
• External bias for higher efficiency supports 8V - 36V input
• Output and input current monitor
• Selectable PWM mode operation between PWM/DE/Burst modes
• Accurate EN/UVLO and PGOOD indicator
• Low shutdown current: 2.7µA
• Complete protection: OCP, SCP, OVP, OTP, and UVP
  •     Dual-level OCP protection with average current and pulse-by-pulse peak current limit
  •     Selectable OCP response with either hiccup or constant current mode
  •     Negative pulse-by-pulse peak current limit

Target applications

• Medical equipment
• Industrial automation equipment
• Battery backup
• Aftermarket automotive (e.g., USB Type-C battery charging)
• Renewable energy systems
• Home automation
• Telecommunications
• Robotics
   

Evaluation board

The ISL81601EVAL1Z evaluation board features the ISL81601, a 60V high voltage synchronous buck-boost controller that offers external soft-start, independent enable functions and integrates UV/OV/OC/OT protection. A programmable switching frequency ranging from 100kHz to 600kHz helps to optimize inductor size while the strong gate driver delivers up to 20A for the buck-boost output.