DATASHEET ISL81601 FN9299 Rev.3.1 60V Bidirectional 4-Switch Synchronous Buck-Boost Controller May 27, 2021 The ISL81601 is a true bidirectional 4-switch Features synchronous buck-boost controller with peak and Single inductor 4-switch buck-boost controller average current sensing and monitoring at both ends. Its On-the-fly bidirectional operation with independent wide input and output voltage ranges make it suitable for control of voltage and current on both ends industrial, telecommunication, and after-market automotive applications. Proprietary algorithm for smoothest mode transition The ISL81601 uses the proprietary buck-boost control MOSFET drivers with adaptive shoot-through algorithm with valley current modulation for Boost mode protection and peak current modulation for Buck mode control. Wide input voltage range: 4.5V to 60V The ISL81601 has four independent control loops for input Wide output voltage range: 0.8V to 60V and output voltages and currents. Inherent peak current sensing at both ends and cycle-by-cycle current limit of Supports pre-biased output with SR soft-start this family of products ensures high operational reliability Programmable frequency: 100kHz to 600kHz by providing instant current limit in fast transient Supports parallel operation current sharing with conditions at either ends and in both directions. It also has cascade phase interleaving two current monitoring pins at both input and output to facilitate Constant Current (CC) limit and other system External sync with clock out or frequency dithering management functions. CC operation down to low External bias for higher efficiency supports 8V - 36V voltages avoids any runaway condition at over load or input short-circuit conditions. In addition to multilayer overcurrent protection, it also provides full protection Output and input current monitor features such as OVP, UVP, OTP, and average and peak Selectable PWM mode operation between current limit on both input and output to ensure high PWM/DE/Burst modes reliability in both unidirectional and bidirectional Accurate EN/UVLO and PGOOD indicator operation. The IC is packaged in a space conscious 32 Ld 5mm x5mm QFN package or easy to assemble Low shutdown current: 2.7A 4.4mmx9.7mm 38 Ld HTSSOP package. Both packages Complete protection: OCP, SCP, OVP, OTP, and UVP use an EPAD to improve thermal dissipation and noise immunity. Low pin count, fewer external components, and Dual-level OCP protection with average current default internal values make the ISL81601 an ideal and pulse-by-pulse peak current limit solution for quick to market simple power supply designs. Selectable OCP response with either hiccup or The unique DE/Burst mode at light-load dramatically constant current mode lowers standby power consumption with consistent output Negative pulse-by-pulse peak current limit ripple over different load levels. Applications R R s out s in VIN VOUT Battery backup UPS/storage systems Q1 Q4 UG2 UG1 L Battery powered industrial applications PH1 PH2 Renewable energy Q2 Q3 LG1 LG2 Aftermarket automotive Redundant power supplies Robot and drones Figure 1. Buck-Boost Power Train Topology Medical equipment Building and industrial automation Security surveillance FN9299 Rev.3.1 Page 1 of 53 May 27, 2021 2018 Renesas ElectronicsISL81601 VIN VOUT FB IN VDD BOOT1 VDD PGND UG1 VCC5V PHASE1 IMON IN ISL81601 QFN LG1/ IMON OUT PWM MODE SGND LG2/ PLL COMP OC MODE RT/SYNC PHASE2 SS/TRK UG2 COMP VDD FB OUT BOOT2 Figure 2. Typical Application Diagram 100 90 80 70 60 50 Vin = 9V Vin = 12V 40 Vin = 24V Vin = 36V Vin = 48V Vin = 60V 30 02468 10 Output Current (A) Figure 3. Efficiency (V = 12V, DE Mode) OUT FN9299 Rev.3.1 Page 2 of 53 May 27, 2021 CLKOUT/ DITHER BSTEN CLKEN OV EN/UVLO PGOOD Efficiency (%) EXTBIAS VIN ISEN- CS+ ISEN+ CS-