TOTX173

2001-08-10

3

5. Application Circuit

6. Applicable optical fiber with fiber optic connectors

TOCP172−

7. Precautions during use

(1)

Maximum rating

The maximum ratings are the limit values which must not be exceeded when using the device. Any

one of the rating must not be exceeded. If The maximum rating is exceeded, the characteristics may

not be recovered. In some extreme cases, the device may be permanently damage.

(2)

Life of light emitters

When the optical module is used for over a long period, degeneration of characteristics is mostly due

to lowering of the fiber output power (Pf). This is caused by the degradation of the optical output of

the LED’s used as the light source. The cause of degradation of the optical output of the LED’ may be

defects in wafer crystallization or mold resin stress. The detailed causes are, however, not clear.

The life of light emitters is greatly influenced by operating conditions and usage environment as well

as the life characteristics unique to the device. Thus, when selecting a light emitter and setting the

operating conditions, Toshiba recommends that you check the life characteristics.

Depending on the environment conditions, Toshiba recommends maintenance such as regular checks

on the amount of optical output.

(3)

Soldering

Optical modules use semiconductor devices internally. However, in principle, optical modules are

optical components. At soldering, take care that flux dose not contact the emitting surface or detecting

surface. Also take care at flux removal after soldering.

Some optical modules come with protective cap. The protective cap is used to avoid malfunction when

the optical module is not in use. Not that it is not dust or waterproof.

As mentioned before, optical modules are optical component. Thus, in principle, soldering where there

may be flux residue or flux removal after soldering is not recommended. Toshiba recommends that

soldering be performed without the optical module mounted on the board. Then, after the board is

cleaned, solder the optical module manually. Do not perform any further cleaning.

If the optical module cannot be soldered manually, use non−halogen (chlorine−free) flux and make

sure, without cleaning, there is no residue such as chlorine. This is one of the ways to eliminate the

effects of flux.

(4)

Vibration and shock

This module is resin−molded construction with wire fixed by resin. This structure is relatively sound

against vibration or shock, In actual equipment, there are some cases where vibration, shock, and

stress is applied to soldered parts or connected parts, resultingin line cut. Attention must be paid to

the design of the mechanism for applications which are subject to large amounts of vibration.

(5)

Fixing fiber optical transceiving module

Solder the fixed pin (pins 5 and 6) of fiber optic transmitting module TOTX173 to the printed circuit

board to fix the module to the board.