PCA8574_PCA8574A_2

© NXP B.V. 2007. All rights reserved.

Product data sheet

Rev. 02 — 14 May 2007

24 of 27

NXP Semiconductors

PCA8574/74A

[1]

For more detailed information on the BGA packages refer to the

(LF)BGA Application Note (AN01026); order a copy from your NXP

Semiconductors sales office.

[2]

All surface mount (SMD) packages are moisture sensitive. Depending upon the moisture content, the maximum temperature (with

respect to time) and body size of the package, there is a risk that internal or external package cracks may occur due to vaporization of

the moisture in them (the so called popcorn effect).

[3]

For SDIP packages, the longitudinal axis must be parallel to the transport direction of the printed-circuit board.

[4]

Hot bar soldering or manual soldering is suitable for PMFP packages.

[5]

These transparent plastic packages are extremely sensitive to reflow soldering conditions and must on no account be processed

through more than one soldering cycle or subjected to infrared reflow soldering with peak temperature exceeding 217

°C ± 10 °C

measured in the atmosphere of the reflow oven. The package body peak temperature must be kept as low as possible.

[6]

These packages are not suitable for wave soldering. On versions with the heatsink on the bottom side, the solder cannot penetrate

between the printed-circuit board and the heatsink. On versions with the heatsink on the top side, the solder might be deposited on the

heatsink surface.

[7]

If wave soldering is considered, then the package must be placed at a 45

° angle to the solder wave direction. The package footprint

must incorporate solder thieves downstream and at the side corners.

[8]

Wave soldering is suitable for LQFP, QFP and TQFP packages with a pitch (e) larger than 0.8 mm; it is definitely not suitable for

packages with a pitch (e) equal to or smaller than 0.65 mm.

[9]

Wave soldering is suitable for SSOP, TSSOP, VSO and VSSOP packages with a pitch (e) equal to or larger than 0.65 mm; it is definitely

not suitable for packages with a pitch (e) equal to or smaller than 0.5 mm.

[10] Image sensor packages in principle should not be soldered. They are mounted in sockets or delivered pre-mounted on flex foil.

However, the image sensor package can be mounted by the client on a flex foil by using a hot bar soldering process. The appropriate

soldering profile can be provided on request.

Surface mount

VFBGA, XSON

not suitable

suitable

−

DHVQFN, HBCC, HBGA, HLQFP,

HSO, HSOP, HSQFP, HSSON,

HTQFP, HTSSOP, HVQFN,

HVSON, SMS

suitable

−

suitable

suitable

−

LQFP, QFP, TQFP

suitable

−

SSOP, TSSOP, VSO, VSSOP

suitable

−

not suitable

not suitable

−

Table 11.

Mounting

Soldering method

Wave

Dipping