参数资料
型号: 74AHCT541
厂商: NXP Semiconductors N.V.
英文描述: Octal buffer/line driver; 3-state(八通道缓冲器/线驱动器;三态;)
中文描述: 八路缓冲器/线路驱动器,3态(八通道缓冲器/线驱动器,三态;)
文件页数: 13/16页
文件大小: 81K
代理商: 74AHCT541
1999 Nov 24
13
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74AHC541; 74AHCT541
SOLDERING
Introduction to soldering surface mount packages
Thistextgivesaverybriefinsighttoacomplextechnology.
A more in-depth account of soldering ICs can be found in
our “Data Handbook IC26; Integrated Circuit Packages”
(document order number 9398 652 90011).
There is no soldering method that is ideal for all surface
mount IC packages. Wave soldering is not always suitable
for surface mount ICs, or for printed-circuit boards with
high population densities. In these situations reflow
soldering is often used.
Reflow soldering
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 methods exist for reflowing; for example,
infrared/convection heating in a conveyor type oven.
Throughput times (preheating, soldering and cooling) vary
between 100 and 200 seconds depending on heating
method.
Typical reflow peak temperatures range from
215 to 250
°
C. The top-surface temperature of the
packages should preferable be kept below 230
°
C.
Wave soldering
Conventional single wave soldering is not recommended
forsurfacemountdevices(SMDs)orprinted-circuitboards
with a high component density, as solder bridging and
non-wetting can present major problems.
To overcome these problems the double-wave soldering
method was specifically developed.
If wave soldering is used the following conditions must be
observed for optimal results:
Use a double-wave soldering method comprising a
turbulent wave with high upward pressure followed by a
smooth laminar wave.
For packages with leads on two sides and a pitch (e):
– larger than or equal to 1.27 mm, the footprint
longitudinal axis is
preferred
to be parallel to the
transport direction of the printed-circuit board;
– smaller than 1.27 mm, the footprint longitudinal axis
must
be parallel to the transport direction of the
printed-circuit board.
The footprint must incorporate solder thieves at the
downstream end.
Forpackageswithleadsonfoursides,thefootprintmust
be placed at a 45
°
angle to the transport direction of the
printed-circuit board. The footprint must incorporate
solder thieves downstream and at the side 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.
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.
Manual soldering
Fix the component by first soldering two
diagonally-opposite end leads. Use a low voltage (24 V or
less) soldering iron 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.
相关PDF资料
PDF描述
74AHC541 Octal buffer/line driver; 3-state
74AHC541PWDH Octal buffer/line driver; 3-state
74AHCT573 Octal D-type transparent latch;3-state(八D透明锁存器;三态)
74AHC573 Quadruple 2-Input Positive-NAND Gates With Open-Drain Outputs 14-SOIC -40 to 85
74AHC573PWDH Quadruple 2-Input Positive-NAND Gates With Open-Drain Outputs 14-SOIC -40 to 85
相关代理商/技术参数
参数描述
74AHCT541ABQX 功能描述:74AHCT541ABQ SOT764 DHVQFN20 制造商:nexperia usa inc. 系列:74AHCT 包装:剪切带(CT) 零件状态:在售 逻辑类型:缓冲器,非反向 元件数:1 每元件位数:8 输入类型:TTL 输出类型:三态 电流 - 输出高,低:8mA,8mA 电压 - 电源:4.5 V ~ 5.5 V 工作温度:-40°C ~ 125°C(TA) 安装类型:表面贴装 封装/外壳:20-VFQFN 裸露焊盘 标准包装:1
74AHCT541APWJ 功能描述:Buffer, Non-Inverting 1 Element 8 Bit per Element Push-Pull Output 20-TSSOP 制造商:nxp semiconductors 系列:74AHCT 包装:带卷(TR) 零件状态:有效 逻辑类型:缓冲器,非反向 元件数:1 每元件位数:8 输入类型:- 输出类型:推挽式 电流 - 输出高,低:8mA,8mA 电压 - 电源:4.5 V ~ 5.5 V 工作温度:-40°C ~ 125°C(TA) 安装类型:表面贴装 封装/外壳:20-TSSOP(0.173",4.40mm 宽) 供应商器件封装:20-TSSOP 标准包装:2,500
74AHCT541BQ 制造商:NXP Semiconductors 功能描述:Bulk 制造商:NXP Semiconductors 功能描述:IC OCT BUFF/DRV TRI-ST DHV
74AHCT541BQ,115 功能描述:缓冲器和线路驱动器 5V OCTAL BUFFER/LINE RoHS:否 制造商:Micrel 输入线路数量:1 输出线路数量:2 极性:Non-Inverting 电源电压-最大:+/- 5.5 V 电源电压-最小:+/- 2.37 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:MSOP-8 封装:Reel
74AHCT541BQ-G 功能描述:缓冲器和线路驱动器 5V OCTAL BUFFER/LINE DRIVER RoHS:否 制造商:Micrel 输入线路数量:1 输出线路数量:2 极性:Non-Inverting 电源电压-最大:+/- 5.5 V 电源电压-最小:+/- 2.37 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:MSOP-8 封装:Reel