PCA9673D datasheet(28/33 Pages) PHILIPS

28 / 33 page

PCA9673_1

Product data sheet

Rev. 01 — 1 February 2007

28 of 33

NXP Semiconductors

PCA9673

Remote 16-bit I/O expander for Fm+ I2C-bus with interrupt and reset

15. Handling information

Inputs and outputs are protected against electrostatic discharge in normal handling.

However, to be completely safe you must take normal precautions appropriate to handling

integrated circuits.

16. Soldering

This text provides a very brief insight into a complex technology. A more in-depth account

of soldering ICs can be found in Application Note

AN10365 “Surface mount reﬂow

soldering description”.

16.1 Introduction to soldering

Soldering is one of the most common methods through which packages are attached to

Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both

the mechanical and the electrical connection. There is no single soldering method that is

ideal for all IC packages. Wave soldering is often preferred when through-hole and

Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not

suitable for ﬁne pitch SMDs. Reﬂow soldering is ideal for the small pitches and high

densities that come with increased miniaturization.

16.2 Wave and reﬂow soldering

Wave soldering is a joining technology in which the joints are made by solder coming from

a standing wave of liquid solder. The wave soldering process is suitable for the following:

• Through-hole components

• Leaded or leadless SMDs, which are glued to the surface of the printed circuit board

Not all SMDs can be wave soldered. Packages with solder balls, and some leadless

packages which have solder lands underneath the body, cannot be wave soldered. Also,

leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered,

due to an increased probability of bridging.

The reﬂow soldering process involves applying solder paste to a board, followed by

component placement and exposure to a temperature proﬁle. Leaded packages,

packages with solder balls, and leadless packages are all reﬂow solderable.

Key characteristics in both wave and reﬂow soldering are:

• Board speciﬁcations, including the board ﬁnish, solder masks and vias

• Package footprints, including solder thieves and orientation

• The moisture sensitivity level of the packages

• Package placement

• Inspection and repair

• Lead-free soldering versus PbSn soldering

16.3 Wave soldering

Key characteristics in wave soldering are:

PCA9673D датащи(PDF) 28 Page - NXP Semiconductors

PCA9673D датащи(HTML) 28 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

датащи скачать

ссылки URL