RT6321A数据手册Richtek中文资料规格书

描述 Description

The RT6321 is high efficiency synchronous step-down DC-DC converters with pseudo constant switching frequency 500kHz and deliver up to 12A output current. The RT6321 operates from 4.5V to 23V input voltage. The output voltage of RT6321 is programmed between 0.6V to 5.5V. The RT6321 supports low power mode (LPM) to dynamically change output voltage between target voltage and zero voltage.The RT6321 adopts Advanced Constant On-Time (ACOT®) control architecture that provides ultra-fast transient response and further reduces the external component count. In steady states, the ACOT® operates at nearly constant switching frequency over line, load and output voltage ranges and makes the EMI filter design easier.By setting the voltage of the EN/MODE pin, RT6321 operates either in diode emulation mode (DEM) or ultrasonic mode (USM) at light load. The USM maintains operation frequency above 25kHz, which eliminates the acoustic noise. In the DEM, RT6321 provides the best light-load efficiency and improves the acoustic noise with spread spectrum function.RT6321 provides PGOOD indicator for easy system sequence control. Full protection features are also integrated in the device, including the cycle-by-cycle current limit, OVP, UVP, input UVLO and OTP.All above functions are integrated in a UQFN-26L 4x3 (FC) package.

特性 Features

Input Voltage Range: 4.5V to 23V
Output Voltage: 0.6V to 5.5V
12A Continuous Output Current
Stable with POSCAP and MLCC Capacitor
Fast Transient Response
Diode Emulation Mode (DEM) for Power Saving
Ultrasonic Mode (USM) for Avoiding Acoustic Noise
Pseudo Constant Switching Frequency 500kHz in CCM
Low-Power Mode (LPM)
Internal Power MOSFET Switch 17mΩ (high-side) and 7.5mΩ (low-side)
Overcurrent Limit: Adjustable (14A, 16A or 18A)
Output Under-/Overvoltage Protection (UVP/OVP) ► RT6321A: Latched Mode UVP/OVP ► RT6321AH: Hiccup Mode UVP and Non-Latched Mode OVP
Input Undervoltage-Lockout (UVLO)
Over-Temperature Protection (OTP) ► RT6321A: Latched Mode OTP ► RT6321AH: Non-Latched Mode OTP
Junction Temperature Range: -40°C to 125°C

应用 Application

• Laptop Computers
• Tablet PCs
• Networking Systems
• Servers
• Personal Video Recorders
• Flat Panel Television and Monitors
• Distributed Power Systems