HX3406

HX3406 is a CMOS step-down DC/DC regulator comprising a voltage reference, oscillator circuit, comparator, and PWM/PFM control circuit. By utilizing automatic PWM/PFM switching control to achieve adjustable duty cycle, it features low ripple, high efficiency, and high output current across the full input voltage range (1.8–5.5V). The HX3406 integrates a power MOSFET and incorporates multiple protection circuits including overvoltage, overcurrent, overtemperature, and short-circuit protection, which automatically disconnect the circuit when control thresholds are exceeded to protect the IC. Combining a compact package with low quiescent current consumption, this product is ideally suited for use in power supplies of mobile devices.

Applications

• Power supply for mobile devices such as digital cameras, electronic organizers, and PDAs
• Power supply for audio devices such as portable CD players and MDs
• Regulated power supply for cameras, video equipment, and communication equipment; microcomputer power supply

Key features

• High efficiency, up to 95% maximum efficiency
• High output current up to 800mA
• Ultra-low quiescent current, typical 40μA
• Very low output ripple <±0.4%
• Low voltage operation with up to 100% duty cycle; automatic PWM/PFM switching with auto-adjustable duty cycle for high efficiency and low ripple across a wide load range