TN0991 Datasheet, PDF (1/21 Pages) STMicroelectronics – Description of WLCSP for STMicroelectronics EEPROMs and recommendations for use

TN0991
Technical note
Description of WLCSP for STMicroelectronics EEPROMs and
recommendations for use
Introduction
This document describes the 5 and 8-bump WLCSPs (wafer level chip size package) used
for STMicroelectronics EEPROM products, and provides recommendation on how to use
them.
The competitive market of portable equipment, in particular the mobile phone market, is
driven by the challenging development of highly integrated devices. To allow manufacturers
of portable equipment to minimize the dimension of their devices, STMicroelectronics has
developed WLCSP with reduced size, thickness and weight. The electrical performance of
such components is improved by using shorter connections than in standard plastic
packages such as TSSOP, SSOP or QFN.
The WLCSP family has been designed to fulfill the same quality levels and same reliability
performance as standard semiconductor plastic packages. As a consequence these new
WLCSP can be considered as new surface mount devices which are assembled on a printed
circuit board (PCB) without any special or additional process steps. In particular these
packages do not require any extra underfill to increase reliability performance or to protect
the device. These packages are compatible with existing pick-and-place equipment for
board mounting. Only Lead-free RoHS compliant WLCSP are available in mass production.
This document addresses the following topics:
• Package description
• Device marking
• Packing specifications and labelling
• Storage and shipping recommendations
• Soldering assembly recommendations
• Package changes
• Package quality
July 2013
DocID024463 Rev 2
www.st.com
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