- 您现在的位置：买卖IC网 > PDF目录69254 > PTH08T255WAZT (TEXAS INSTRUMENTS INC) DC-DC REG PWR SUPPLY MODULE PDF资料下载
参数资料
| 型号： | PTH08T255WAZT |
| 厂商： | TEXAS INSTRUMENTS INC |
| 元件分类： | 电源模块 |
| 英文描述： | DC-DC REG PWR SUPPLY MODULE |
| 封装： | PLASTIC, MODULE-22 |
| 文件页数： | 34/34页 |
| 文件大小： | 4336K |
| 代理商： | PTH08T255WAZT |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页当前第34页
CAPACITOR RECOMMENDATIONS FOR THE PTH08T255W POWER MODULE
Capacitor Technologies
Input Capacitor (Required)
Input Capacitor Information
www.ti.com ........................................................................................................................................................................................... SLTS290 – NOVEMBER 2008
Electrolytic Capacitors
When using electrolytic capacitors, high quality, computer-grade electrolytic capacitors are recommended.
Aluminum electrolytic capacitors provide adequate decoupling over the frequency range, 2 kHz to 150 kHz,
and are suitable when ambient temperatures are above -20°C. For operation below -20°C, tantalum,
ceramic, or OS-CON type capacitors are required.
Ceramic Capacitors
Above 150 kHz the performance of aluminum electrolytic capacitors is less effective. Multilayer ceramic
capacitors have very low ESR and a resonant frequency higher than the bandwidth of the regulator. They
can be used to reduce the reflected ripple current at the input as well as improve the transient response of
the output.
Tantalum, Polymer-Tantalum Capacitors
Tantalum type capacitors may only be used on the output bus, and are recommended for applications where
the ambient operating temperature is less than 0°C. The AVX TPS series and Kemet capacitor series are
suggested over many other tantalum types due to their lower ESR, higher rated surge, power dissipation,
and ripple current capability. Tantalum capacitors that have no stated ESR or surge current rating are not
recommended for power applications.
The PTH08T255W requires a minimum input capacitance of 1000F. The ripple current rating of the input
capacitor must be at least 750 mArms. An optional 22F X5R/X7R ceramic capacitor is recommended to reduce
RMS ripple current.
The size and value of the input capacitor is determined by the converter’s transient performance capability. This
minimum value assumes that the converter is supplied with a responsive, low inductance input source. This
source should have ample capacitive decoupling, and be distributed to the converter via PCB power and ground
planes.
Ceramic capacitors should be located as close as possible to the module's input pins, within 0.5 inch (1,3 cm).
Adding ceramic capacitance is necessary to reduce the high-frequency ripple voltage at the module's input. This
reduces the magnitude of the ripple current through the electroytic capacitor, as well as the amount of ripple
current reflected back to the input source. Additional ceramic capacitors can be added to further reduce the RMS
ripple current requirement for the electrolytic capacitor.
The main considerations when selecting input capacitors are the RMS ripple current rating, temperature stability,
and less than 100 m
of equivalent series resistance (ESR).
Regular tantalum capacitors are not recommended for the input bus. These capacitors require a recommended
minimum voltage rating of 2 × (maximum dc voltage + ac ripple). This is standard practice to ensure reliability.
No tantalum capacitors were found with a sufficient voltage rating to meet this requirement.
When the operating temperature is below 0°C, the ESR of aluminum electrolytic capacitors increases. For these
applications, OS-CON, poly-aluminum, and polymer-tantalum types should be considered.
Copyright 2008, Texas Instruments Incorporated
9
Product Folder Link(s): PTH08T255W
相关PDF资料 |
PDF描述 |
|---|---|
| PTH08T255WAST | DC-DC REG PWR SUPPLY MODULE |
| PTH08T255WAD | DC-DC REG PWR SUPPLY MODULE |
| PTH08T261WAD | 1-OUTPUT DC-DC REG PWR SUPPLY MODULE |
| PTH08T260WAST | 1-OUTPUT DC-DC REG PWR SUPPLY MODULE |
| PTH08T261WAST | 1-OUTPUT DC-DC REG PWR SUPPLY MODULE |
相关代理商/技术参数 |
参数描述 |
|---|---|
| PTH08T260W | 制造商:TI 制造商全称:Texas Instruments 功能描述:3-A, 4.5-V to 14-V INPUT, NON-ISOLATED, WIDE-OUTPUT, ADJUSTABLE POWER MODULE WITH TurboTrans |
| PTH08T260WAD | 功能描述:DC/DC转换器 3-A 4.5V to 14V Input RoHS:否 制造商:Murata 产品: 输出功率: 输入电压范围:3.6 V to 5.5 V 输入电压（标称）: 输出端数量:1 输出电压（通道 1）:3.3 V 输出电流（通道 1）:600 mA 输出电压（通道 2）: 输出电流（通道 2）: 安装风格:SMD/SMT 封装 / 箱体尺寸: |
| PTH08T260WAS | 功能描述:DC/DC转换器 3-A 4.5V to 14V Input RoHS:否 制造商:Murata 产品: 输出功率: 输入电压范围:3.6 V to 5.5 V 输入电压（标称）: 输出端数量:1 输出电压（通道 1）:3.3 V 输出电流（通道 1）:600 mA 输出电压（通道 2）: 输出电流（通道 2）: 安装风格:SMD/SMT 封装 / 箱体尺寸: |
| PTH08T260WAST | 功能描述:DC/DC转换器 3-A 4.5V to 14V Input RoHS:否 制造商:Murata 产品: 输出功率: 输入电压范围:3.6 V to 5.5 V 输入电压（标称）: 输出端数量:1 输出电压（通道 1）:3.3 V 输出电流（通道 1）:600 mA 输出电压（通道 2）: 输出电流（通道 2）: 安装风格:SMD/SMT 封装 / 箱体尺寸: |
| PTH08T260WAZ | 功能描述:DC/DC转换器 3-A 4.5V to 14V Input RoHS:否 制造商:Murata 产品: 输出功率: 输入电压范围:3.6 V to 5.5 V 输入电压（标称）: 输出端数量:1 输出电压（通道 1）:3.3 V 输出电流（通道 1）:600 mA 输出电压（通道 2）: 输出电流（通道 2）: 安装风格:SMD/SMT 封装 / 箱体尺寸: |
发布紧急采购，3分钟左右您将得到回复。