TI公司的LMZ21701是容易使用的SIMPLE SWITCHER? Nano模塊，小型3.5 mm × 3.5mm× 1.75 mm封裝，驅(qū)動電流高達1A，輸入電壓3V-17V，輸出電壓0.9V-6V，效率高達95%，主要用在照相機監(jiān)測IP網(wǎng)絡，工業(yè)監(jiān)視器，軟件定義無線電電（SDR），DLP光譜，示波器和TV等。本文介紹了LMZ21701主要特性和功能框圖， 評估模塊LMZ21701 EVM主要特性，電路 材料清單和PCB設計文件。

The LMZ21701 SIMPLE SWITCHER? Nano Module is an easy-to-use step-down DC-DC solution capable of driving up to 1000 mA load in space-constrained applications. Only an input capacitor， an output capacitor， a softstart capacitor， and two resistors are required for basic operation. The Nano Module comes in 8-pin DFN footprint package with an integrated inductor. The LMZ21701 architecture is based on DCS-Control? （Direct Control with Seamless Transition into Power Save Mode）。 This architecture combines the fast transient response and stability of hysteretic type converters along with the accurate DC output regulation of voltage mode and current mode regulators.

The LMZ21701 architecture uses Pulse Width Modulation （PWM） mode for medium and heavy load requirements and Power Save Mode （PSM） at light loads for high efficiency. In PWM mode the switching frequency is controlled over the input voltage range. The value depends on the output voltage setting and is typically reduced at low output voltages to achieve higher efficiency. In PSM the switching frequency decreases linearly with the load current. Since the architecture of the device supports both operation modes （PWM and PSM） in a single circuit building block， the transition between the modes of operation is seamless with minimal effect on the output voltage.

LMZ21701主要特性：

Integrated Inductor

Miniature 3.5 mm × 3.5 mm × 1.75 mm Package

35 mm2 Solution Size （Single Sided）

–40 °C to 125 °C Junction Temperature Range

Adjustable Output Voltage

Integrated Compensation

Adjustable Soft Start Function

Starts into Pre-Biased Loads

Power Good and Enable Pins

Seamless Transition to Power-Save Mode

Up to 1000 mA Output Current

Input Voltage Range 3 V to 17 V

Output Voltage Range 0.9 V to 6 V

Efficiency up to 95 %

1.5 μA Shutdown Current

17 μA Quiescent Current