</a>DC/DC转换器" title="DC/DC转换器">DC/DC转换器" title="DC/DC转换器">DC/DC转换器,采用电流模式控制,简化外部补偿和灵活选择元件,工作静态电流90uA,关端电流1.4uA,开关频率50kHz到1100kHz可调,主要用在4-20mA电流回路传感器,工业过程控制,计量和安全系统,高效地替代高压线性稳压器.本文介绍了TPS54061主要特性,方框图,CCM和DCM应用电路图以及TPS54061EVM-142评估板电路图,材料清单和PCB元件布局图.

The TPS54061 device is a 60-V, 200-mA,synchronous step-down DC-DC converter with integrated high side and low side MOSFETs. Current  mode control provides simple external compensation and flexible component selection. The non-switching supply current is 90 μA. Using the enable pin, shutdown supply current is reduced to 1.4 μA.

To increase light load efficiency the low side  MOSFET emulates a diode when the inductor current reaches zero.
 
Under voltage lockout is internally set at 4.5 V, but can be increased using two resistors on the enable pin. The output voltage startup ramp is controlled by  the internal slow start time.

The adjustable switching frequency range allows  efficiency and external component size to be  optimized. Frequency foldback and thermal shutdown  protects the part during an overload condition.
 
The TPS54061 enables small designs by integrating  the MOSFETs, boot recharge diode, and minimizing  the IC footprint with a small 3mm x 3mm thermally enhanced VSON package

TPS54061主要特性:

• Integrated High Side and Low Side MOSFET

• Diode Emulation for Improved Light Load Efficiency

• Peak Current Mode Control

• 90 μA Operating Quiescent Current .

• 1.4 μA Shutdown Supply Current

• 50 kHz to 1100 kHz Adjustable Switching Frequency

• Synchronizes to External Clock

• Internal Slow Start

• 0.8 V ±1% Voltage Reference

• Stable with Ceramic Output Capacitors or Low Cost Aluminum Electrolytic

• Cycle-by-Cycle Current Limit, Thermal, OVP and Frequency Fold Back Protection

• VSON-8 Package, 3 mm X 3 mm With Thermal Pad

• –40℃ to 150℃ Operating Junction Temperature

TPS54061应用:

• 4-20 mA Current-Loop Powered Sensors

• Low Power Standby or Bias Voltage Supplies EFFICIENCY

• Industrial Process Control, Metering, and Security Systems

• High Efficiency Replacement for High Voltage Linear Regulators

图1.TPS54061方框图

图2.TPS54061 CCM应用电路图

图3.TPS54061 DCM应用电路图

图4.TPS54061EVM-142评估板电路图

TPS54061EVM-142评估板材料清单:



图5.TPS54061EVM-142评估板元件布局图
详情请见:
http://www.ti.com/lit/ds/slvsbb7a/slvsbb7a.pdf
和
http://www.ti.com/lit/ug/slvu721/slvu721.pdf