SC121ULTRT

The SC121ULTRT is a high efficiency, low noise, synchronous step-up DC-DC converter that provides boosted voltage levels in low-voltage handheld applications. The wide input voltage range allows use in systems with single NiMH or alkaline battery cells as well as in systems with higher voltage battery supplies. It features an internal 1.2A switch and synchronous rectifier to achieve up to 94% efficiency and to eliminate the need for an external Schottky diode. The output voltage can be set to 3.3V with internal feedback, or to any voltage within the specified range using a standard resistor divider.The SC121ULTRT operates exclusively in Pulse Width Modulation (PWM) mode for low ripple and fixed-frequency switching. Output disconnect capability is included to reduce leakage current, improve efficiency, and eliminate external components sometimes needed to disconnect the load from the supply during shutdown.Low quiescent current is maintained with a high 1.2MHz operating frequency. Small external components and the space saving MLPD-UT-6, 1.5×2.0×0.6 (mm) package make this device an excellent choice for small handheld applications that require the longest possible battery life.

• Input voltage - 0.7V to 4.5V
• Minimum start-up voltage - 0.85V
• Output voltage - fixed at 3.3V; adjustable from 1.8V to 5.0V
• Peak input current limit - 1.2A
• Output current at 3.3 Vout - 80mA with VIN = 1.0V
• 190mA with Vin = 1.5V
• Forced PWM operation at all loads
• Efficiency up to 94%
• Internal synchronous rectifier
• No forward conduction path during shutdown
• Switching frequency - 1.2MHz
• Soft-start startup current limiting
• Shutdown current - 0.1µA (typ)
• Ultra-thin 1.5 × 2.0 × 0.6 (mm) MLPD-UT-6 package
• Lead-free and halogen-free
• WEEE and RoHS compliant