Intelligent Semiconductor Analyzer User Manual 16 17. 1.Introduction ... the Anode of the diode is...

Please read this manual before switching the unit on.

Important safety information inside.

Intelligent Semiconductor Analyzer

User Manual

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Intelligent Semiconductor Analyzer User Manual

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Contents

1.Introduction ...........................................................................

2.Important Considerations ......................................................

3.Analysin Gsemiconductors......................................................

3-1.Diodes...............................................................................

3-2.Diodes Network...............................................................

3-3.LEDS.................................................................................

3-4.Bicolour LEDS...................................................................

3-5.Bipolar Junction Transistor................................................

3-6.Transistor Special Features................................................

3-7.Faulty or Very Low Gain Transistors...................................

3-8.Current Gain (HFE)............................................................

3-9.Base-Emitter Voltage Drop................................................

3-10.Collector Leakage Current...............................................

3-11.Mosfets...........................................................................

3-12.Junction FETS Are conventional Field Effect Transistors...

3-13.Thyristors........................................................................

4.Battery Replacement................................................................

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1.IntroductionComponents tester is an intelligent semiconductor analyser thatoffers great features together with refreshing simplicity. The Testerbrings a world of component data to your fingertips.1.Automatic component type identification•Bipolar transistors•Darlington transistors•Enhancement Mode MOSFETS•Depletion Mode MOSFETS•Junction FETS•Low power sensitive Triacs•Low power sensitive Thyristors•Light Emitting Diodes•Bicolour LEDS•Diodes•Diode networks2.Automatic pinout identification, just connect any way round.3.Special feature identification such as diode protection and resistor

shunts.4.Gain measurement for bipolar transistors.5.Leakage current measurement for bipolar transistors.6.Silicon and Germanium detection for bipolar transistors.7.Gate threshold measurement for Enhancement Mode Mosfets.8.Semiconductor forward voltage measurement for diodes, LEDS and

transistor Base-Emitter junctions.9.Automatic and manual power-off.

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2.Important ConsiderationsThe Tester is designed to analyse discrete, unconnected, unpoweredcomponents. This ensures that external connections don’t influencethe measured parameters. The three test probes can be connectedto the component any way round. If the component hasonly twoterminals, then any pair of the three test probes can be used.

The Tester will start component analysis when the ON/Analyse buttonis pressed if the unit is powered down. If the Tester is not powereddown then a new analysis can be started by pressing and holdingthe OFF/Page button first to power down the unit and then pressingthe ON/Analyse button.

Depending on the component type, analysis may take a few secondsto complete, after which, the results of the analysis are displayed.Information is displayed a “page” at a time, each page can be displayedby briefly pressing the OFF/Page button.

The arrow symbol on the display indicates that more pages are availableIf the cannot detect any componentbetween any of the test probes, thefollowing message will be displayed:

If the component is not a supportedcomponent type, a faulty componentor a component that is being testedin-circuit, the analysis may result in thefollowing message being displayed:

Some components may be faulty dueto a shorted junction between a pairof the probes. If this is the case, thefollowing message (or similar) will bedisplayed:

If all three probes are shorted (or verylow resistance) then the followingmessage will be displayed:

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No ComponentDetected

Unknown/FaultyComponent

Short Circuit OnGreen Blue

Short Circuit OnGreen Blue Red

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It is possible that the Tester may detect one or more diode junctionsor other component type within an unknown or faulty part.This is because many semiconductors comprise of PN (diode) junctions.Please refer to the section on diodes and diode networks for moreinformation.

The Tester will analyse almost any type of diode. Any pair of the threetest clips can be connected to the diode, any way round. If the unitdetects a single diode, the following message will be displayed:

Pressing the OFF/Page button will thendisplay the pinout for the diode. Inthis example, the Anode of the diodeis connected to the Red test clip andthe Cathode is connected to the Greentest clip, additionally, the Blue test clipis unconnected. The forward voltagedrop is then displayed, this gives anindication of the diode technology. Inthis example, it is likely that the diodeis a silicon diode. A germanium orSchottky diode may yield a forwardvoltage of about 0.25V. The current atwhich the diode was tested is alsodisplayed.

The Tester will determine that the diode(s) under test is an LEDif the measured forward voltage drop exceeds 1.50V. Please refer tothe section on LED analysis for more information.

3.Analysin Gsemiconductors3-1.Diodes

Diode Or DiodeJunction(s)

Forward VoltageVf=0.64V

Test CurrentIf=4.38mA

Red Green BlueAnod Cath

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3-2.Diodes NetworkThe Tester will intelligently identify popular types of three terminaldiode networks. For three terminal devices such as SOT-23 diodenetworks, the three test clips must all be connected, any way round.The instrument will identify the type of diode network and thendisplay information regarding each detected diode in sequence. Thefollowing types of diode networks are automatically recognised bythe Tester:

Both cathodes connected together,such as the BAV70 device.

Anodes of each diode are connectedtogether, the BAW56W is an example.

Here, each diode is connected in series.An example is the BAV99.

Following the component identification,the details of each diode in the networkwill be displayed.

Firstly, the pinout for the diode is displayed,followed by the electrical information,forward voltage drop and the currentat which the diode was tested. Thevalue of the test current depends onthe measured forward voltage dropof the diode.

Following the display of all the details for the first diode, the detailsof the second diode will then be displayed.

Common CathodeDiode Network

Series diodenetwork

Pinout for D1...

Common AnodeDiode Network


Forward VoltageD2 Vf=0.64V

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3-3.LEDSAn LED is really just a another type of diode, however, the Tester willdetermine that an LED or LED network has been detected if themeasured forward voltage drop is larger than 1.5V. This also enablesthe Tester to intelligently identify bicolour LEDs, both two-terminaland three-terminal varieties.

Like the diode analysis, the pinout, theforward voltage drop and the associatedtest current is displayed.

Here, the Cathode (-ve) LED terminal isconnected to the Green test clip andthe Anode (+ve) LED terminal is connectedto the Blue test clip.

In this example, a simple green LEDyields a forward voltage drop of 1.87V.

The test current is dependant on theforward voltage drop of the LED, herethe test current is measured as 3.15mA.

Some blue LEDS (and their cousins, white LEDS) require high forwardvoltages and may not be detected by the Tester.

Led Or DiodeJunction(s)

Forward VoltageVf=1.87V

Test CurrentIf=3.15mA

Red Green BlueCath Anod

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3-4.Bicolour LEDSBicolour LEDS are automatically identified. If your LED has 3 leadsthen ensure they are all connected, in any order.A two terminal bicolour LED consists of two LED chips which areconnected in inverse parallel within the LED body. Three terminalbicolour LEDS are made with either common anodes or commoncathodes.

Here a two terminal LED has beendetected.

This message will be displayed if theunit has detected a three terminal LED.

The details of each LED in the packagewill then be displayed in a similar wayto the diode networks detailed earlier.

The pinout for the 1st LED is displayed.Remember that this is the pinout for justone of the two LEDS in the package.

Interestingly, the voltage drops for eachLED relate to the different colours withinthe bicolour LED. It may therefore bepossible to determine which lead isconnected to each colour LED withinthe device. Red LEDs often have thelowest forward voltage drop, followedby yellow LEDS, green LEDs and finally,blue LEDS.

Two TerminalBicolour LED

Pinout for D1...


Three TerminalBicolour LED

Forward VoltageD1 Vf=1.98V

Test Current

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3-5.Bipolar Junction TransistorBipolar Junction Transistors are simply "conventional" transistors,although variants of these do exist such as Darlingtons, diode protected,resistor shunted types and combinations of these types. All of thesevariations are automatically identified by the Tester.

Bipolar Junction Transistors are availablein two main types, NPN and PNP. Inthis example, the unit has detected aSilicon PNP transistor.

The unit will determine that thetransistor is Germanium only if thebase-emitter voltage drop is less than0.4V and is also PNP.

If the device is a Darlington transistor(two BJTs connected together), the unitwill display a similar message to this:

Pressing the OFF/Page button will resultin the transistor's pinout being displayed.

Here, the instrument has identified thatthe Base is connected to the Red testclip, the Collector is connected to theGreen test clip and the Emitter isconnected to the Blue test clip.

PNP SiliconTransistor

NPN DarlingtonTransistor

Red Green BlueBase Coll Emit

PNP GermaniumTransistor

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3-6.Transistor Special FeaturesMany modern transistors contain additional special features. If theTester has detected any special features, then the details of thesefeatures are displayed next after pressing the OFF/Page button. Ifthere are no special features detected then the next screen will bethe transistor’s current gain.Some transistors, particularly CRTdeflection transistors and many largeDarlingtons have a protection diodeinside their package connected betweenthe collector and emitter.

The Philips BU505DF is a typical example of a diode protected bipolartransistor. Remember that protection diodes are always internallyconnected between the collector and the emitter so that they arenormally reverse biased.

For NPN transistors, the anode of the diode is connected to the emitterof the transistor. For PNP transistors, the anode of the diode isconnected to the collector of the transistor.

Additionally, many Darlingtons and a few non-Darlington transistorsalso have a resistor shunt network between the base and emitter ofthe device.

The Tester can detect the resistor shunt if it has a resistance of typicallyless than 60k .

The popular Motorola TIP110 NPN Darlington transistor containsinternal resistors between the base and emitter.

When the unit detects the presenceof a resistive shunt between the baseand emitter, the display will show:

Additionally, the Tester will warn youthat the accuracy of gain measurement(HFE) has been affected by the shuntresistor.

Ω

Diode ProtectionBetween C-E

Resistor ShuntBetween B-E

HFE Not AccurateDue To B-E Res

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3-7.Faulty or Very Low Gain Transistors

3-8.Current Gain (HFE)

Faulty transistors that exhibit very lowgain may cause the Tester to only identifyone or more diode junctions withinthe device. This is because NPN transistorsconsist of a structure of junctions thatbehave like a common anode diodenetwork. PNP transistors can appearto be common cathode diode networks.The common junction represents thebase terminal. This is normal for situationswhere the current gain is so low thatit is immeasurable at the test currentsused by the Tester.

In some circumstances, the unit maynot be able to deduce anything sensiblefrom the device at all, in which caseyou will see either of these messages

The DC current gain (HFE) is displayed after any special transistorfeatures have been displayed.

The gain of all transistors can varyconsiderably with collector current,collector voltage and also temperature.The displayed value for gain thereforemay not represent the gain experiencedat other collector currents and voltages.This is particularly true for large devices.

Darlington transistors can have very high gain values and morevariation of gain will be evident as a result of this.

Additionally, it is quite normal for transistors of the same type tohave a wide range of gain values. For this reason, transistor circuitsare often designed so that their operation has little dependence on

Common AnodeDiode Network

Unknown/FaultyComponent

No ComponentDetected

Current GainHFE=119

Test CurrentIc=2.50mA

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the absolute value of current gain.The displayed value of gain is very useful however for comparingtransistors of a similar type for the purposes of gain matching orfault finding.

The DC characteristics of the base-emitter junction are displayed,both the base-emitter forward voltage drop and the base currentused for the measurement.

The forward base-emitter voltage dropcan aid in the identification of siliconor germanium devices. Germaniumdevices can have base-emitter voltagesas low as 0.2V, Silicon types exhibitreadings of about 0.7V and Darlingtontransistors can exhibit readings ofabout 1.2V because of the multiplebase-emitter junctions being measured.

The collector current that takes place when no base current is flowingis referred to as Leakage Current. Most modern transistor exhibit

extremely low values of leakage current, often less than 1 A, evenfor very high collector-emitter voltages.

Older Germanium types however cansuffer from significant collector leakagecurrent, particular at high temperatures(leakage current can be very temperaturedependant).

If your transistor is a Silicon type, you should expect to see a leakagecurrent of close to 0.00mA unless the transistor is faulty.

3-9.Base-Emitter Voltage Drop

3-10.Collector Leakage Current

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B-E VoltageVbe=0.72V

Test CurrentIB=4.48mA

Leakage CurrentIC=0.15mA

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3-11.MosfetsMosfet stands for Metal OxideSemiconductor Field Effect Transistor.Like bipolar transistors, Mosfets areavailable in two main types, N-Channeland P-Channel. Most modern Mosfetsare of the Enhancement Mode type,meaning that the bias of the gate-sourcevoltage is always positive (For N-Channeltypes). The other (rarer) type of Mosfetis the Depletion Mode type which isdescribed in a later section.

Mosfets of all types are sometimes known as Igfets, meaning InsulatedGate Field Effect Transistor. This term describes a key feature of thesedevices, an insulated gate region that results in negligible gate currentfor both positive and negative gate-source voltages (up to themaximum allowed values of course, typically ±20V).

The first screen to be displayed givesinformation on the type of Mosfetdetected. Pressing OFF/Page will thenresult in the pinout of the Mosfet beingdisplayed. The gate, source and drainare each identified.

An important feature of a Mosfet is thegate-source threshold voltage, the gate-source voltage at which conductionbetween the source and drain starts.The gate threshold is displayed followingthe pinout information.

Enhancement ModN-Ch MOSFET

Red Green BlueGate Drn Srce

Gate ThresholdVgs=3.47V

Test CurrentId=2.50mA

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The fairly rare Depletion Mode Mosfet is very similar to the conventionalJunction FET (JFET) except that the gate terminal is insulated fromthe other two terminals. The input resistance of these devices cantypically be greater than 1000M for negative and positive gate-sourcevoltages.

Depletion Mode devices are characterisedby the gate-source voltage requiredto control the drain-source current.

Modern Depletion Mode devices are generally only available inN-Channel varieties and will conduct current between it's drain andsource terminals even with a zero voltage applied across the gateand the source. The device can only be turned completely off bytaking it's gate significantly more negative than it's source terminal,say -10V. It is this characteristic that makes them so similar toconventional Jfets.

Pressing OFF/Page will cause thepinout screen to be displayed.

The voltage applied across the gate-source terminals controls currentbetween the drain and source terminals. N-Channel Jfets require anegative voltage on their gate with respect to their source, the morenegative the voltage, the less current can flow between the drainand source.Unlike Depletion Mode Mosfets, Jfetshave no insulation layer on the gate.This means that although the inputresistance between the gate and sourceis normally very high, the gate currentcan rise if the semiconductor junctionbetween the gate and source or betweenthe gate and drain become forwardbiased. This can happen if the gatevoltage becomes about 0.6V higher

Ω

3-12.Junction FETS Are conventional Field Effect Transistors

Depletion ModeN-CH Mosfet

Red Green BlueDrn Gate Srce

P-ChannelJunction FET

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than either the drain or source terminalsfor N-Channel devices or 0.6V lowerthan the drain or source for P-Channeldevices.

The internal structure of Jfets is essentiallysymmetrical about the gate terminal,this means that the drain and sourceterminals are indistinguishable by theTester. The JFET type and the gateterminal are identified however.

Sensitive low power thyristors (silicon Controlled Rectifiers-scrs) andtriacs that require gate currents and holding currents of less than5mA can be identified and analysed with the Tester.Thyristor terminals are the anode,cathode and the gate. The pinout ofthe thyristor under test will be displayedon the next press of the OFF/Page button.

Triac terminals are the MT1, MT2 (MTstanding for main terminal) and gate.MT1 is the terminal with which gatecurrent is referenced.

3-13.Thyristors

Drain And SourceNot Identified

Red Green BlueGate

Sensitive Or LowPower Thyristor

Red Green BlueGate Anod Cath

Sensitive Or LowPower Triac

Red Green BlueMT1 MT2 Gate

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4.Battery ReplacementTester should provide many years of service if used in accordancewith this user guide. Care should be taken not to expose your unitto excessive heat, shock or moisture. Additionally, the battery shouldbe replaced at least every 12 months to reduce the risk of leak damage.

If a low battery warning messageappears, immediate replacement of thebattery is recommended as measuredparameters may be affected. The unitmay however continue to operate.

The battery can be replaced by carefully opening the Tester by removingthe three screws from the rear of the unit. Take care not to damagethe electronics.

The battery should only be replaced with a high quality battery identicalto, or equivalent to an Alkaline GP23A or MN21 12V (10mm diameterx 28mm length).

Low Battery

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Rev.

100505


Intelligent Semiconductor Analyzer User Manual 16 17. 1.Introduction ... the Anode of the diode is...

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