TMPR4956C datasheet(34/286 Pages) TOSHIBA

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Handling Precautions

(3) Make sure that no surge voltages from the measuring equipment are applied to the device.

(4) The chips in tape carrier packages (TCPs) are LSI chips and therefore exposed. During inspection, be

careful not to crack or scratch the chip.

Electrical contact may also cause chip failure. Therefore make sure that nothing comes into electrical

contact with the chip.

3.5

Mounting

There are two types of device packages: lead insertion and surface mount. The items that affect reliability during

circuit board mounting include contamination by flux and thermal stress during the soldering process. With

surface-mount devices in particular, the most significant problem is thermal stress from solder reflow, when the

entire package is subjected to heat. In addition, the mounting method differs according to factors such as chip

size and frame design, even for the same package type. For details, refer to the individual technical datasheets

and databooks for each device.

When a location such as a soldered area, connecting area or top surface of a device is subjected to vibration,

impact or in actual equipment, bonding fault or device destruction may result. Therefore, be sure to keep this in

mind at the time of mounting. If a device is subject to especially strong vibration, impact or stress, the package

or chip may crack. Thus, at the time of mounting, carefully consider vibration, impact and stress.

3.5.1

Lead Forming

[1] Always wear safety glasses when cutting the leads of a device with clippers or a similar

tool. Failure to do so may result in eye damage from the small shavings that fly off the

cut ends.

[2] Do not touch the lead tips of a device.

Some devices have leads withsharp tips. Contact to sharp tips may result in a puncture

wound.

Semiconductor devices sometimes undergo a process in which the leads are cut and formed before the devices

are installed on a printed circuit board. If abnormal stress is applied to the interior of a device during this process,

mechanical breakdown or reliability deterioration may result. This is attributable mainly to the relative stress

applied between the device itself and the lead, and can result in internal lead damage, adhesive property

deterioration and sealant breakdown. Observe the following precautions during the lead-forming process.

(This does not apply to surface-mount devices.)

(1) Lead insertion hole intervals on the printed circuit board should be designed using the same dimension

standard as that for the lead interval of the device.

(2) If the lead insertion hole intervals on the printed circuit board do not match the lead interval of the device,

do not forcibly insert the device.

TMPR4956C Datasheet(PDF) 34 Page - Toshiba Semiconductor