5秒后页面跳转
SAA5297A PDF预览

SAA5297A

更新时间: 2024-10-27 22:43:31
品牌 Logo 应用领域
恩智浦 - NXP 微控制器电视
页数 文件大小 规格书
68页 614K
描述
Economy teletext and TV microcontrollers

SAA5297A 数据手册

 浏览型号SAA5297A的Datasheet PDF文件第62页浏览型号SAA5297A的Datasheet PDF文件第63页浏览型号SAA5297A的Datasheet PDF文件第64页浏览型号SAA5297A的Datasheet PDF文件第65页浏览型号SAA5297A的Datasheet PDF文件第67页浏览型号SAA5297A的Datasheet PDF文件第68页 
Philips Semiconductors  
Preliminary specification  
Economy teletext and TV microcontrollers  
SAA5x9x family  
Reflow soldering requires solder paste (a suspension of  
fine solder particles, flux and binding agent) to be applied  
to the printed-circuit board by screen printing, stencilling or  
pressure-syringe dispensing before package placement.  
18 SOLDERING  
18.1 Introduction  
There is no soldering method that is ideal for all IC  
packages. Wave soldering is often preferred when  
through-hole and surface mounted components are mixed  
on one printed-circuit board. However, wave soldering is  
not always suitable for surface mounted ICs, or for  
printed-circuits with high population densities. In these  
situations reflow soldering is often used.  
Several techniques exist for reflowing; for example,  
thermal conduction by heated belt. Dwell times vary from  
50 to 300 seconds depending on heating method. Typical  
reflow temperatures range from 215 to 250 °C.  
Preheating is necessary to dry the paste and evaporate  
the binding agent. Preheat for 45 minutes at 45 °C.  
This text gives a very brief insight to a complex technology.  
A more in-depth account of soldering ICs can be found in  
our “IC Package Databook” (order code 9398 652 90011).  
18.3.2 WAVE SOLDERING  
Wave soldering is not recommended for QFP packages.  
This is because of the likelihood of solder bridging due to  
closely-spaced leads and the possibility of incomplete  
solder penetration in multi-lead devices.  
18.2 SDIP  
18.2.1 SOLDERING BY DIPPING OR BY WAVE  
The maximum permissible temperature of the solder is  
260 °C; solder at this temperature must not be in contact  
with the joint for more than 5 seconds. The total contact  
time of successive solder waves must not exceed  
5 seconds.  
If wave soldering cannot be avoided, the following  
conditions must be observed:  
A double-wave (a turbulent wave with high upward  
pressure followed by a smooth laminar wave)  
soldering technique should be used.  
The device may be mounted up to the seating plane, but  
the temperature of the plastic body must not exceed the  
specified maximum storage temperature (Tstg max). If the  
printed-circuit board has been pre-heated, forced cooling  
may be necessary immediately after soldering to keep the  
temperature within the permissible limit.  
The footprint must be at an angle of 45° to the board  
direction and must incorporate solder thieves  
downstream and at the side corners.  
Even with these conditions, do not consider wave  
soldering the following packages: QFP52 (SOT379-1),  
QFP100 (SOT317-1), QFP100 (SOT317-2),  
QFP100 (SOT382-1) or QFP160 (SOT322-1).  
18.2.2 REPAIRING SOLDERED JOINTS  
During placement and before soldering, the package must  
be fixed with a droplet of adhesive. The adhesive can be  
applied by screen printing, pin transfer or syringe  
dispensing. The package can be soldered after the  
adhesive is cured. Maximum permissible solder  
temperature is 260 °C, and maximum duration of package  
immersion in solder is 10 seconds, if cooled to less than  
150 °C within 6 seconds. Typical dwell time is 4 seconds  
at 250 °C.  
Apply a low voltage soldering iron (less than 24 V) to the  
lead(s) of the package, below the seating plane or not  
more than 2 mm above it. If the temperature of the  
soldering iron bit is less than 300 °C it may remain in  
contact for up to 10 seconds. If the bit temperature is  
between 300 and 400 °C, contact may be up to 5 seconds.  
18.3 QFP  
18.3.1 REFLOW SOLDERING  
A mildly-activated flux will eliminate the need for removal  
of corrosive residues in most applications.  
Reflow soldering techniques are suitable for all QFP  
packages.  
18.3.3 REPAIRING SOLDERED JOINTS  
The choice of heating method may be influenced by larger  
plastic QFP packages (44 leads, or more). If infrared or  
vapour phase heating is used and the large packages are  
not absolutely dry (less than 0.1% moisture content by  
weight), vaporization of the small amount of moisture in  
them can cause cracking of the plastic body. For more  
information, refer to the Drypack chapter in our “Quality  
Reference Handbook” (order code 9397 750 00192).  
Fix the component by first soldering two diagonally-  
opposite end leads. Use only a low voltage soldering iron  
(less than 24 V) applied to the flat part of the lead. Contact  
time must be limited to 10 seconds at up to 300 °C. When  
using a dedicated tool, all other leads can be soldered in  
one operation within 2 to 5 seconds between  
270 and 320 °C.  
1997 Jul 07  
66  

与SAA5297A相关器件

型号 品牌 获取价格 描述 数据表
SAA5297AH NXP

获取价格

Economy teletext and TV microcontrollers
SAA5297AH/NNN NXP

获取价格

IC 8-BIT, MROM, 12 MHz, MICROCONTROLLER, PQFP80, 14 X 20 MM, 2.80 MM HEIGHT, PLASTIC, SOT-
SAA5297APS NXP

获取价格

Economy teletext and TV microcontrollers
SAA5297APS/NNN NXP

获取价格

IC 8-BIT, MROM, 12 MHz, MICROCONTROLLER, PDIP52, 0.600 INCH, PLASTIC, SDIP-52, Microcontro
SAA5297H NXP

获取价格

Economy teletext and TV microcontrollers
SAA5297H/NNN NXP

获取价格

IC 8-BIT, MROM, 12 MHz, MICROCONTROLLER, PQFP80, Microcontroller
SAA5297PS NXP

获取价格

Economy teletext and TV microcontrollers
SAA5297PS/NNN NXP

获取价格

IC 8-BIT, MROM, 12 MHz, MICROCONTROLLER, PDIP52, 0.600 INCH, PLASTIC, SDIP-52, Microcontro
SAA5351 PHILIPS

获取价格

Display Controller, Bipolar, PDIP40
SAA5355 NXP

获取价格

Single-chip colour CRT controller FTFROM