参数资料
型号: LM2677LDX-5.0
厂商: NATIONAL SEMICONDUCTOR CORP
元件分类: 稳压器
英文描述: 8.75 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, PDSO14
封装: LLP-14
文件页数: 3/26页
文件大小: 449K
代理商: LM2677LDX-5.0
Application Hints (Continued)
DESIGN CONSIDERATIONS
Power supply design using the LM2677 is greatly simplified
by using recommended external components. A wide range
of inductors, capacitors and Schottky diodes from several
manufacturers have been evaluated for use in designs that
cover the full range of capabilities (input voltage, output
voltage and load current) of the LM2677. A simple design
procedure using nomographs and component tables pro-
vided in this data sheet leads to a working design with very
little effort. Alternatively, the design software, LM267X Made
Simple (version 6.0), can also be used to provide instant
component selection, circuit performance calculations for
evaluation, a bill of materials component list and a circuit
schematic.
The individual components from the various manufacturers
called out for use are still just a small sample of the vast
array of components available in the industry. While these
components are recommended, they are not exclusively the
only components for use in a design. After a close compari-
son of component specifications, equivalent devices from
other manufacturers could be substituted for use in an ap-
plication.
Important considerations for each external component and
an explanation of how the nomographs and selection tables
were developed follows.
INDUCTOR
The inductor is the key component in a switching regulator.
For efficiency the inductor stores energy during the switch
ON time and then transfers energy to the load while the
switch is OFF.
Nomographs are used to select the inductance value re-
quired for a given set of operating conditions. The nomo-
graphs assume that the circuit is operating in continuous
mode (the current flowing through the inductor never falls to
zero). The magnitude of inductance is selected to maintain a
10130107
FIGURE 1. Basic circuit for fixed output voltage applications.
10130108
FIGURE 2. Basic circuit for adjustable output voltage applications
LM2677
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相关PDF资料
PDF描述
LM2677LD-3.3 8.75 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, PDSO14
LM2677LDX-12 8.75 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, PDSO14
LM2677LD-12 8.75 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, PDSO14
LM2677SDX-3.3/NOPB 8.75 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, DSO14
LM2677SDX-5.0/NOPB 8.75 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, DSO14
相关代理商/技术参数
参数描述
LM2677S-12 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
LM2677S-12/NOPB 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
LM2677S-12/NOPB 制造商:Texas Instruments 功能描述:DC/DC Converter IC
LM2677S-3.3 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
LM2677S-3.3/NOPB 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT