參數(shù)資料
型號: SAA4995WP
廠商: NXP SEMICONDUCTORS
元件分類: 消費家電
英文描述: Panorama-IC (PAN-IC)(全景畫面IC)
中文描述: SPECIALTY CONSUMER CIRCUIT, PQCC44
封裝: PLASTIC, SOT-187, LCC-44
文件頁數(shù): 14/16頁
文件大小: 107K
代理商: SAA4995WP
1997 Jun 10
14
Philips Semiconductors
Preliminary specification
PANorama-IC (PAN-IC)
SAA4995WP
SOLDERING
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.
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).
Reflow soldering
Reflow soldering techniques are suitable for all PLCC
packages.
The choice of heating method may be influenced by larger
PLCC 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 9398 510 63011).
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.
Several techniques exist for reflowing; for example,
thermal conduction by heated belt. Dwell times vary
between 50 and 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. Preheating duration: 45 minutes at
45
°
C.
Wave soldering
Wave soldering techniques can be used for all PLCC
packages if the following conditions are observed:
A double-wave (a turbulent wave with high upward
pressure followed by a smooth laminar wave) soldering
technique should be used.
The longitudinal axis of the package footprint must be
parallel to the solder flow.
The package footprint must incorporate solder thieves at
the downstream corners.
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.
A mildly-activated flux will eliminate the need for removal
of corrosive residues in most applications.
Repairing soldered joints
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.
相關(guān)PDF資料
PDF描述
SAA55XX TV microcontrollers with Closed Captioning (CC) and On-Screen Display (OSD)
SAA6712E ECONOLINE: RB & RA - Dual Output from a Single Input Rail- Power Sharing on Output- Industry Standard Pinout- 1kVDC & 2kVDC Isolation- Custom Solutions Available- UL94V-0 Package Material- Efficiency to 85%
SAA6713AH XGA analog input flat panel controller
SAA6713H XGA dual input flat panel controller
SAA7110 Digital Multistandard Colour Decoder(數(shù)字多標準彩色譯碼器)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
SAA4996H 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Motion Adaptive Colour Plus And Control IC MACPACIC for PALplus
SAA4997H 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:VErtical Reconstruction IC VERIC for PALplus
SAA4998H 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Field and line rate converter with noise reduction and embedded memory
SAA50 制造商:Anglo Adhesives 功能描述:RS STRUCT ACRYLC ADH 50ML
SAA5191 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Teletext video processor