DATASHEET ISL91110 FN8434 Rev 4.00 High Efficiency Buck-Boost Regulator with 4.5A Switches February 5, 2016 The ISL91110 is a high-current buck-boost switching regulator Features for systems using new battery chemistries. It uses Intersils Accepts input voltages above or below regulated output proprietary buck-boost algorithm to maintain voltage voltage regulation while providing excellent efficiency and very low output voltage ripple when the input voltage is close to the Automatic and seamless transitions between buck and output voltage. boost modes The ISL91110 is capable of delivering at least 2A continuous Input voltage range: 1.8V to 5.5V output current (V = 3.3V) over a battery voltage range of OUT Output current: up to 2A (PVIN = 2.5V, V = 3.3V) OUT 2.5V to 4.35V. This maximizes the energy utilization of Burst current: up to 3A (PVIN = 3V, V = 3.3V, t < OUT ON advanced single-cell Li-ion battery chemistries that have 600s, t = 4.6ms) significant capacity left at voltages below the system voltage. Its fully synchronous low ON-resistance 4-switch architecture High efficiency: up to 96% and a low quiescent current of only 35A optimize efficiency 35A quiescent current maximizes light-load efficiency under all load conditions. 2.5MHz switching frequency minimizes external component The ISL91110 supports standalone applications with a fixed size 3.3V or 3.5V output voltage or adjustable output voltage with Fully protected for short-circuit, over-temperature, and an external resistor divider. Output voltages as low as 1.0V or undervoltage as high as 5.2V are supported. Small 2.33mmx2.07mm WLCSP The ISL91110 is available in a 25-bump, 0.4mm pitch WLCSP (2.33mmx2.07mm) and a 2.5MHz switching frequency, which Applications further reduces the size of external components. Brownout free system voltage for smartphones and tablet PCs Wireless communication devices 2G/3G/4G RF power amplifiers Related Literature AN1912 ISL91110IIN-EVZ, ISL91110II2A-EVZ, ISL91110IIA-EVZ Evaluation Boards 100 V = 4.0V IN ISL91110IINZ V 1.8V TO 5.5V IN = LX1 95 PVIN C L 1 1 1H 2x10F V = 3.3V 90 LX2 OUT VIN I = UP TO 3A OUT V = 3.6V IN VOUT V = 3.3V IN EN C 2 V = 3.0V IN 2x22F 85 FB MODE V = 2.5V IN 80 NOTE: Confirm with Intersil Applications Engineer for any deviation 75 1 10 100 1000 from above circuit LOAD CURRENT (mA) FIGURE 1. TYPICAL APPLICATION: V = 3.3V FIGURE 2. EFFICIENCY: V = 3.3V, T = +25C OUT OUT A FN8434 Rev 4.00 Page 1 of 12 February 5, 2016 SGND PGND EFFICIENCY (%)ISL91110 Block Diagram LX1 LX2 B4 B1 B2 B3 D1 D2 D3 D4 A4 A3 Q1 E1 PVIN A2 E2 Q4 VOUT A1 E3 GATE DRIVERS E4 & ANTI- EN B5 EN SHOOT THRU Q3 Q2 C1 VIN A5 V REF EN C2 PGND C3 VIN MONITOR VOUT CLAMP THERMAL C5 SHUTDOWN SGND CURRENT D5 DETECT EN CONTROL D3 MODE ADJ OSC OUTPUT EN ERROR FB E5 AMP FIXED REF OUTPUT COMP VOLTAGE PROG. FIGURE 3. BLOCK DIAGRAM FN8434 Rev 4.00 Page 2 of 12 February 5, 2016 REVERSE CURRENT