ISL9120IIAZ-T

The ISL9120IR is a highly integrated buck-boost switching regulator that accepts input voltages above or below the regulated output voltage. The regulator automatically transitions between buck and boost modes without significant disturbance to the output. When the input voltage is typically within 1% to 2% of the output voltage, the ISL9120IR also features an automatic bypass function, providing a direct bypass connection between the VIN and VOUT pins. In addition to automatic bypass, the ISL9120IR supports forced bypass via the BYPS pin. The device delivers up to 800mA of output current (VIN = 2.5V, VOUT = 3.3V), with its adaptive current-limit pulse frequency modulation (PFM) control architecture enabling excellent efficiency. The ISL9120IR is designed for standalone applications, supporting either a fixed 3.3V output or a variable output voltage set by an external resistor divider. If voltage regulation is not required, a forced bypass power-saving mode can be selected. In forced bypass mode, the device draws less than 3.5µA of current across the operating temperature range. The ISL9120IR requires only a single inductor and minimal external components. The 3mm×3mm 12-pin TQFN package minimizes the footprint of the power solution.

Applications

• Smartphones and tablets
• Portable consumer and wearable devices

Key features

• Accepts input voltage above or below the regulated output voltage
• Auto-bypass mode
• Automatic seamless transition between step-down and step-up modes
• Input voltage range: 1.8V to 5.5V
• Selectable forced bypass power-saving mode
• Adaptive multi-level current limiting scheme for optimized efficiency at high and low currents
• Output current: up to 800mA (VIN = 2.5V, VOUT = 3.3V)
• High efficiency: up to 98%
• 41µA quiescent current for maximum light-load efficiency
• Full over-temperature and undervoltage protection
• Compact 3mm×3mm 12-pin TQFN package