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aPPenDiX C MOunTinG PReCauTiOnS
aP-C-2
Seiko epson Corporation
S1C17153 TeChniCal Manual
(Rev. 1.0)
Signal line location
• To prevent electromagnetically-induced noise arising from mutual induction, large-current signal lines should
not be positioned close to circuits susceptible to noise, such as oscillators.
• Locating signal lines in parallel over significant distances or crossing signal lines operating at high speed will
cause malfunctions due to noise generated by mutual interference. Specifically, avoid positioning crossing
signal lines operating at high speed close to circuits susceptible to noise, such as oscillators.
handling of light (for bare chip mounting)
The characteristics of semiconductor components can vary when exposed to light. ICs may malfunction or non-
volatile memory data may be corrupted if ICs are exposed to light.
Consider the following precautions for circuit boards and products in which this IC is mounted to prevent IC
malfunctions attributable to light exposure.
(1) Design and mount the product so that the IC is shielded from light during use.
(2) Shield the IC from light during inspection processes.
(3) Shield the IC on the upper, underside, and side faces of the IC chip.
(4) Mount the IC chip within one week of opening the package. If the IC chip must be stored before mounting,
take measures to ensure light shielding.
(5) Adequate evaluations are required to assess nonvolatile memory data retention characteristics before prod-
uct delivery if the product is subjected to heat stress exceeding regular reflow conditions during mounting
processes.
unused pins
(1) I/O port (P) pins
Unused pins should be left open. The control registers should be fixed at the initial status (input with pull-
up enabled).
(2) OSC1 and OSC2 pins
If the OSC1A oscillator circuit is not used, the OSC1 and OSC2 pins should be left open. The control regis-
ters should be fixed at the initial status (oscillation disabled).
(3) V
C1–3
, CA, CB, SEG
x
, and COM
x
pins
If the LCD driver is not used, these pins should be left open. The control registers should be fixed at the
initial status (display off). The unused SEG
x
pins that are not required to connect should be left open even
if the LCD driver is used.
Miscellaneous
This product series is manufactured using microscopic processes.
Although it is designed to ensure basic IC reliability meeting EIAJ and MIL standards, minor variations over
time may result in electrical damage arising from disturbances in the form of voltages exceeding the absolute
maximum rating when mounting the product in addition to physical damage. The following factors can give
rise to these variations:
(1) Electromagnetically-induced noise from industrial power supplies used in mounting reflow, reworking after
mounting, and individual characteristic evaluation (testing) processes
(2) Electromagnetically-induced noise from a solder iron when soldering
In particular, during soldering, take care to ensure that the soldering iron GND (tip potential) has the same po-
tential as the IC GND.