原标题：NS LMZ10505EXT 5A SIMPLE SWITCHER电源方案

　　NS 公司的LMZ10505EXT 是5A SIMPLE SWITCHER电源模块，最大输入电压5.5V，符合军用标准。LMZ10505EXT电源模块的最大输出功率为25W，输出电流高达5A，输入电压 2.95V- 5.5V，输出电压0.8V - 5V，效率高达96%，主要用在点负载转换，空间受限的应用，极端温度/无空气对流的环境以及对噪音敏感如传感器，医疗设备等。本文介绍了LMZ10505EXT主要特性和电指标，方框图和多种应用电路于相应的材料清单，以及LMZ1050xEXT 评估板主要特性，电路图和材料清单(BOM)。

　　LMZ10505EXT 5A SIMPLE SWITCHER Power Module with 5.5V Maximum Input Voltage for Military and Rugged Applications

　　The LMZ10505EXT SIMPLE SWITCHER power module is a complete, easy-to-use DC-DC solution capable of driving up to a 5A load with exceptional power conversion efficiency, output voltage accuracy, line and load regulation. The LMZ10505EXT is available in an innovative package that enhances thermal performance and allows for hand or machine soldering.

　　The LMZ10505EXT can accept an input voltage rail between 2.95V and 5.5V and deliver an adjustable and highly accurate output voltage as low as 0.8V. One megahertz fixed frequency PWM switching provides a predictable EMI characteristic. Two external compensation components can be adjusted to set the fastest response time, while allowing the option to use ceramic and/or electrolytic output capacitors. Externally programmable soft-start capacitor facilitates controlled startup.

　　The LMZ10505EXT is a reliable and robust solution with the following features: lossless cycle-by-cycle peak current limit to protect for over current or short-circuit fault, thermal shutdown, input under-voltage lock-out, and pre-biased startup.

　　LMZ10505EXT电指标：

　　■ 25W maximum total output power

　　■ Up to 5A output current

　　■ Input voltage range 2.95V to 5.5V

　　■ Output voltage range 0.8V to 5V

　　■ ±1.63% feedback voltage accuracy over temperature

　　■ Efficiency up to 96%

　　LMZ10505EXT主要特性：

　　■ Integrated shielded inductor

　　■ Flexible startup sequencing using external soft-start, tracking, and precision enable

　　■ Protection against in-rush currents and faults such as input UVLO and output short-circuit

　　■ -55℃ to +125℃ junction temperature operating range

　　■ Single exposed pad and standard pinout for easy mounting and manufacturing

　　■ Pin-to-pin compatible with

　　LMZ10503EXT (3A/15W max)

　　LMZ10504EXT (4A/20W max)

　　■ Fully enable for WEBENCH and Power Designer

　　■ Low output voltage ripple of 10 mV allows for powering noise-sensitive transceiver and signaling ICs

　　■ Fast transient response for powering FPGAs and ASICs

　　Performance Benefits

　　■ Operates at high ambient temperatures

　　■ Low radiated emissions (EMI) complies with EN55022 class B standard (Note 2)

　　■ Passes 10V/m radiated immunity EMI test standard EN61000 4-3

　　■ Passes vibration standard MIL-STD-883 Method 2007.2 Condition A

　　JESD22-B103B Condition 1

　　■ Passes drop standard

　　MIL-STD-883 Method 2002.3 Condition B

　　JESD22-B110 Condition B

　　LMZ10505EXT应用：

　　■ Point-of-load conversions from 3.3V and 5V rails

　　■ Space constrained applications

　　■ Extreme temperatures/no air flow environments

　　■ Noise sensitive applications (i.e. transceiver, medical)

　　图1。LMZ10505EXT方框图

　　图2。LMZ10505EXT应用电路图(1)：

　　VIN = 3.3V 到 5V, VOUT = 2.5V, IOUT (MAX) = 5A材料清单：

　　VIN = 3.3V, VOUT = 0.8V, IOUT (MAX) = 5A 材料清单：

　　图3。LMZ10505EXT应用电路图(2)：VIN = 3.3V - 5V, VOUT = 2.5V, IOUT (MAX) = 5A

　　VIN = 3.3V - 5V, VOUT = 2.5V, IOUT (MAX) = 5A材料清单：

　　图4。LMZ10505EXT应用电路图(3)：VIN = 3.3V -5V, VOUT = 2.5V, IOUT (MAX) = 5A

　　VIN = 3.3V -5V, VOUT = 2.5V, IOUT (MAX) = 5A材料清单：

　　图5。LMZ10505EXT应用电路图(4)：VIN = 5V, VOUT = 2.5V, IOUT (MAX) = 5A

　　VIN = 5V, VOUT = 2.5V, IOUT (MAX) = 5A,材料清单：

　　LMZ1050xEXT 评估板

　　The LMZ1050xEXT SIMPLE SWITCHER power module is a complete, easy-to-use DC-DC solution capable of driving up to 3A, 4A, or 5A load with exceptional power conversion efficiency, output voltage accuracy, line and load regulation. The LMZ1050xEXT is available in an innovative package that enhances thermal performance and allows for hand or machine soldering.

　　The LMZ1050xEXT can accept an input voltage rail between 2.95V and 5.5V and deliver an adjustable and highly accurate output voltage as low as 0.8V. One megahertz fixed frequency PWM switching provides a predictable EMI characteristic.

　　Two external compensation components can be adjusted to set the fastest response time, while allowing the option to use ceramic and/or electrolytic output capacitors. Externally programmable soft-start capacitor facilitates controlled startup.

　　The LMZ1050xEXT is a reliable and robust solution with the following features: lossless cycle-by-cycle peak current limit to protect for over current or short-circuit fault, thermal shutdown, input under-voltage lock-out, and pre-biased startup.

　　LMZ1050xEXT 评估板指标：

　　• VIN = 2.95V to 5.5V

　　• VOUT = 2.5V (default output voltage setting)

　　• ±2.5% feedback voltage accuracy at 2.5V output (Including line and load regulation from TJ = -55℃ to 125℃)

　　• ±1.63% feedback voltage accuracy over temperature

　　• IOUT = 0A to 3A, 4A, and 5A

　　• θJA = 20℃/W, θJC = 1.9℃/W

　　• Designed on four layers, the top and bottom layers are 1oz. copper and the two inner

　　layers are 1/2 oz. copper weight

　　• Measures 2.25 in. x 2.25 in. (5.8 cm x 5.8 cm) and is 62mil (.062”) thick on a FR4 laminate

　　Component Schematic for Evaluation Board

　　图6。LMZ1050xEXT 评估板电路图：VIN = 3.3V - 5V, VOUT = 2.5V

　　图6材料清单：

　　图7。LMZ1050xEXT 完整评估板电路图

　　图8。LMZ1050xEXT评估板效率测量框图

　　图9。LMZ10505EXT应用电路图(5)：VIN = 5V, VOUT = 2.5V，符合EN55022 Class B辐射发射标准

　　图9材料清单：