TPS5405DR

TPS5405是一款具有宽运行输入电压范围（6.5V至28V）的单片非同步降压稳压器。该器件采用内部斜率补偿的电流模式控制，以减少组件数量。 TPS5405还具有轻负载脉冲跳跃模式，该特性可在轻负载时降低输入电源的功率损耗。 可通过一个外部电阻器将转换器的开关频率设定在50kHz至1.1MHz之间。频率展频操作可有效减少EMI。 LX抗振铃设计用于解决高频EMI问题。 具有频率折返功能的逐周期电流限制在过载条件下保护IC。 The TPS5405 is a 28-V, 2-A, step-down (buck) converter with an integrated high-side N-channel MOSFET. To improve performance during line and load transients, the device implements a constant frequency, current mode control which reduces output capacitance and simplifies external frequency compensation design. The TPS5405's switching frequency is adjustable with an external resistor or fixed by connecting the frequency program pin to GND or leaving it unconnected. The TPS5405 starts switching at V_IN equal to 3.5 V. The operating current is 100 μA typically when not switching and under no load. When the device is disabled, the supply current is 1 μA typically. The integrated 120 mΩ high-side MOSFET allows for high efficiency power supply designs with continuous output currents up to 2 A. The TPS5405 reduces the external component count by integrating the boot recharge diode. The bias voltage for the integrated high-side MOSFET is supplied by an external capacitor on the BOOT to PH pins. The boot capacitor voltage is monitored by an UVLO circuit and will turn the high-side MOSFET off when the voltage falls below a preset threshold of 2.1 V typically.

Applications

• 9V, 12V, and 24V distributed power systems
• Consumer applications such as home appliances, set-top boxes, CPE equipment, LCD monitors, peripherals, and battery chargers
• Industrial and automotive entertainment system power supplies

Key features

• Fixed 5V output
• Wide input voltage range: 6.5V to 28V
• Maximum continuous output load current up to 2A
• Pulse skip mode for high efficiency at light load
• Efficiency exceeding 80% at 10mA load
• Adjustable switching frequency 50kHz to 1.1MHz set by a single external resistor (leave pin ROSC floating to set frequency to 120kHz)
• Peak current mode control
• Cycle-by-cycle overcurrent protection
• Anti-ringing switch node to mitigate EMI
• External soft-start
• SOIC-8 package