Richtek RT6273B

Description

The RT6273A/B is a simple, easy-to-use, 3A synchronous step-down DC-DC converter with an input supply voltage range of 4.5V to 17V. The device possesses an accurate reference voltage and integrates low RDS(ON) power MOSFETs to achieve high efficiency. The RT6273A/B adopts Advanced Constant On-Time (ACOT® ) control architecture to provide an ultrafast transient response with few external components and to operate in nearly constant switching frequency over the line, load, and output voltage range. The RT6273A operates in automatic PSM that maintains high efficiency during light load operation. The RT6273B operates in Forced PWM that helps meet tight voltage regulation accuracy requirements. The RT6273A/B senses both FETs current for a robust over-current protection (OCP). The device features cycle-by-cycle current limit protection to prevent the device from the catastrophic damage in output short circuit, over-current or inductor saturation conditions. A built-in soft-start function prevents inrush current during start-up. The device also includes input under-voltage lockout, output under-voltage protection, and over-temperature protection (OTP) to provide safe and smooth operation in all operating conditions.

Features

• 3A Converter Integrated 95mΩ and 50mΩ FETs
• Input Supply Voltage Range : 4.5V to 17V
• Maximum Output Voltage Range : 7V
• Advanced Constant On-Time (ACOT®) Control
• Ultrafast Transient Response
• Optimized for Low-ESR Ceramic OutputCapacitors
• High Accuracy Feedback Reference Voltage : Typ.±1%
• Optional for Operation Modes :
• RT6273A : Power Saving Mode (PSM)
• RT6273B : Forced PWM Mode
• Fixed Switching Frequency : 1.4MHz
• Enable Control and Internally Fixed Soft-Start with typ. 1ms
• Input Under-Voltage Lockout (UVLO)
• Protection Function
• Output Under-Voltage Protection (UVP) withHiccup Mode
• High- / Low-side MOSFET OCP and OTP Function
• RoHS Compliant and Halogen Free

Typical applications

• Set-Top Boxes / Home Networking Devices
• LCD TVs

More information

• Datasheet
• IC product information