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[6]  Handling Guide 

 

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[ 6 ]  Handling Guide 

 

1. 

Using Toshiba Semiconductors Safely 

  TOSHIBA is continually working to improve the quality and reliability of its products. 

Nevertheless, semiconductor devices in general can malfunction or fail due to their inherent electrical 
sensitivity and vulnerability to physical stress. It is the responsibility of the buyer, when utilizing 
TOSHIBA products, to comply with the standards of safety in making a safe design for the entire 
system, and to avoid situations in which a malfunction or failure of such TOSHIBA products could 
cause loss of human life, bodily injury or damage to property.   
In developing your designs, please ensure that TOSHIBA products are used within specified operating 
ranges as set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the 
precautions and conditions set forth in the “Handling Guide for Semiconductor Devices,” or 
“TOSHIBA Semiconductor Reliability Handbook” etc.. 

 
The TOSHIBA products listed in this document are intended for usage in general electronics 

applications (computer, personal equipment, office equipment, measuring equipment, industrial 
robotics, domestic appliances, etc.). These TOSHIBA products are neither intended nor warranted for 
usage in equipment that requires extraordinarily high quality and/or reliability or a malfunction or 
failure of which may cause loss of human life or bodily injury (“Unintended Usage”). Unintended 
Usage include atomic energy control instruments, airplane or spaceship instruments, transportation 
instruments, traffic signal instruments, combustion control instruments, medical instruments, all 
types of safety devices, etc.. Unintended Usage of TOSHIBA products listed in this document shall be 
made at the customer’s own risk. 

 

 

Summary of Contents for Semiconductor

Page 1: ...ucts specifications Also please keep in mind the precautions and conditions set forth in the Handling Guide for Semiconductor Devices or TOSHIBA Semiconductor Reliability Handbook etc The TOSHIBA products listed in this document are intended for usage in general electronics applications computer personal equipment office equipment measuring equipment industrial robotics domestic appliances etc The...

Page 2: ...u move on to the detailed descriptions of the precautions Explanation of labels Indicates an imminently hazardous situation which will result in death or serious injury if you do not follow instructions Indicates a potentially hazardous situation which could result in death or serious injury if you do not follow instructions Indicates a potentially hazardous situation which if not avoided may resu...

Page 3: ... device is on do not touch the device s heat sink Heat sinks become hot so you may burn your hand Do not touch the tips of device leads Because some types of device have leads with pointed tips you may prick your finger When conducting any kind of evaluation inspection or testing be sure to connect the testing equipment s electrodes or probes to the pins of the device under test before powering it...

Page 4: ...area are grounded to earth Place a conductive mat over the floor of the work area or take other appropriate measures so that the floor surface is protected against static electricity and is grounded to earth The surface resistivity should be 104 to 108 Ω sq and the resistance between surface and ground 7 5 105 to 108 Ω Cover the workbench surface also with a conductive mat with a surface resistivi...

Page 5: ...gs that are made of anti static materials or materials which dissipate electrostatic charge Make sure that cart surfaces which come into contact with device packaging are made of materials which will conduct static electricity and verify that they are grounded to the floor surface via a grounding chain In any location where the level of static electricity is to be closely controlled the ground res...

Page 6: ...s and devices in canister type packages which have empty space inside them are subject to damage from vibration and shock because the bonding wires are secured only at their ends Plastic molded devices on the other hand have a relatively high level of resistance to vibration and mechanical shock because their bonding wires are enveloped and fixed in resin However when any device or package type is...

Page 7: ...ul especially corrosive gases or in dusty conditions Use storage areas where there is minimal temperature fluctuation Rapid temperature changes can cause moisture to form on stored devices resulting in lead oxidation or corrosion As a result the solderability of the leads will be degraded When repacking devices use anti static containers Do not allow external forces or loads to be applied to devic...

Page 8: ...peration even for an instant Although absolute maximum ratings differ from product to product they essentially concern the voltage and current at each pin the allowable power dissipation and the junction and storage temperatures If the voltage or current on any pin exceeds the absolute maximum rating the device s internal circuitry can become degraded In the worst case heat generated in internal c...

Page 9: ...sumption in comparison with bipolar digital ICs and therefore it only needs a low capacity power supply However in practice CMOS consumes power during transition and therefore it is necessary to keep the high frequency impedance of the power source at a low level It is advisable to make the wiring of the power source VCC and GND lines thick and short and insert as a high frequency filter a capacit...

Page 10: ...o the output and both flow out IOH and flow in IOL current drive is possible For this reason excessive current will flow in a C2MOSTM output when the high level output line is shorted to the GND line or when the low level output line is shorted to the VCC line In particular when the supply voltage is high IOH and IOL are excessive and may damage the device care must be taken not to cause an output...

Page 11: ...ue to their physical and electrical characteristics the Mini MOS Series are apt to cause overshoot and undershoot this leads to malfunction of the circuit or the breakdown of passive ICs These problems can be prevented to some extent by terminating the signal line Figure 3 4 shows examples of termination a Termination Using RC Components b Termination Using Diodes Figure 3 4 Examples of Terminatio...

Page 12: ...to account the timing at power on As the VCC and VSS levels vary from device to device please refer to the datasheet for the device in question 2 Do not subject the device to abnormal noise 3 Fix the potential of any unused input pins to VCC or VSS 4 Do not connect output pins directly to other output pins or to VCC or VSS Since ample margin against latch up is provided there is no problem if Min ...

Page 13: ...ms are malfunction due to induced noise or destruction of the input output elements due to a surge Reducing the signal line impedance driving impedance or inserting noise eliminating circuits on the receiving side are two ways of dealing with the former problem surge protection measures are taken to cope with the latter Figure 3 7 shows an example of noise and surge protection Alternatively the PC...

Page 14: ...that the timing requirements specified in the data sheet be observed When a synchronous signal is used care must be taken with the output signal Figure 3 8 shows an example of how to solve this problem In this case if the difference in phase between CK1 and CK2 is the same as the tpd output clock of the first stage flip flop care must be taken Note If CK1 and CK2 cannot be used together the synchr...

Page 15: ...ich θja thermal resistance between junction and surrounding air C W θjc thermal resistance between junction and package surface or internal thermal resistance C W θca thermal resistance between package surface and surrounding air or external thermal resistance C W Tj junction temperature or chip temperature C Tc package surface temperature or case temperature C Ta ambient temperature C P power dis...

Page 16: ...anate from each component in a piece of equipment For this reason it is only after the prototype equipment has been completed that the designer can take measurements using a dedicated instrument to determine the strength of electromagnetic interference waves Yet it is possible during system design to incorporate some measures for the prevention of electromagnetic interference which can facilitate ...

Page 17: ...ic field surface leakage may occur due to the charge up phenomenon resulting in device malfunction In such cases take appropriate measures to prevent this problem for example by protecting the package surface with a conductive shield 3 With some microcomputers and MOS memory devices caution is required when powering on or resetting the device To ensure that your design does not violate device spec...

Page 18: ... faulty Therefore make sure that nothing comes into electrical contact with the chip 3 5 Mounting There are essentially two main types of semiconductor device package lead insertion and surface mount During mounting on printed circuit boards devices can become contaminated by flux or damaged by thermal stress from the soldering process With surface mount devices in particular the most significant ...

Page 19: ...e Also avoid bending or stretching device leads repeatedly Be careful not to damage the lead during lead forming Follow any other precautions described in the individual datasheets and databooks for each device and package type 3 5 2 Socket Mounting 1 When socket mounting devices on a printed circuit board use sockets which match the inserted device s package 2 Use sockets whose contacts have the ...

Page 20: ...gure 3 10 Heating Top and Bottom with Long or Medium Infrared Rays Complete the infrared ray reflow process within 30 seconds at a package surface temperature of between 210 C and 240 C Refer to Figure 3 11 for an example of a good temperature profile for infrared or hot air reflow Figure 3 11 Sample Temperature Profile for Infrared or Hot Air Reflow 3 Using hot air reflow Complete hot air reflow ...

Page 21: ...methods When immersing devices in a solvent or steam bath make sure that the temperature of the liquid is 50 C or below and that the circuit board is removed from the bath within one minute 5 Ultrasonic cleaning should not be used with hermetically sealed ceramic packages such as a leadless chip carrier LCC pin grid array PGA or charge coupled device CCD because the bonding wires can become discon...

Page 22: ...e cleaned However if the flux used contains only a small amount of halogen 0 05 W or less the devices may be used without cleaning without any problems 3 5 6 Circuit Board Coating When devices are to be used in equipment requiring a high degree of reliability or in extreme environments where moisture corrosive gas or dust is present circuit boards may be coated for protection However before doing ...

Page 23: ... due to the occurrence of electrostatic discharge Unless damp proofing measures have been specifically taken use devices only in environments with appropriate ambient moisture levels i e within a relative humidity range of 40 to 60 3 6 3 Corrosive Gases Corrosive gases can cause chemical reactions in devices degrading device characteristics For example sulphur bearing corrosive gases emanating fro...

Page 24: ...ll adversely affect a device s electrical characteristics To avoid this problem do not use devices in dusty or oily environments This is especially important for optical devices because dust and oil can affect a device s optical characteristics as well as its physical integrity and the electrical performance factors mentioned above 3 6 8 Fire Semiconductor devices are combustible they can emit smo...

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