Officeload793

Simple MOSFET measurements with the 4155parameter analyzer

In a first attempt at measuring a MOSFET, you probably would liketo see a family of drain current vs. drain voltage curves, and thenwould like to extract the parameters V_T, K, and lambdathat could be used as the starting point of a level 2 MOSFET model.Of course, there are a variety of ways to extract parameters. Thetutorial below describes one relatively simple approach. You willhave to make two separate measurements in order to get all threeparameters. The first measurement obtains a conventional family ofi_D vs V_DS curves, and from these you can easilyfind lambda. The second measurement involves plotting the square-rootof the drain current vs. the gate voltage in the saturation region.If you assume the MOSFET has textbook square-law behavior, the draincurrent is given by

Earbuds aiwa mosfet k4145 lcd vivo y85 earbuds 2018 gold blushes led 7 metres gold blu ray led 7 inches mosfet k3324 This product belongs to Home, and you can find similar products at All Categories, Novelty & Special Use, Costumes & Accessories, Kids Costumes & Accessories. K4145 datasheet vdss=60v, n-ch power mosfet nec. بحث داتا شيت العناصر الالكترونية. Product data: condenser microphone cartridges — types 4130. K4145 Datasheet - Vdss=60V, N-Ch Power MOSFET - NEC, 2SK4145 datasheet, K4145 pdf, K4145 pinout, K4145 manual, K4145 schematic, K4145 equivalent. K4145 Datasheet(PDF) 1 Page - VBsemi Electronics Co.,Ltd: Part No. K4145: Description N-Channel 60 V MOSFET: Download 7 Pages: Scroll/Zoom: 100%: Maker. 2SK4145 ( K4145 ) - MOSFET, N channel, 60V, 84A, 84W,0.007 ohm, TO-220 (K4145 ) - MOSFET This seems ideal: STP80NF06 N Channel 60V, 80A, 82W, 0.0065 Ohm, TO-220 STripFET™ II POWER MOSFET.

.

Taking the square-root of both sides gives

,

so that a plot of the square-root of i_D vs.v_GS will look like Fig. 1 below.

With this type of plot, you can easily extract the thresholdvoltage (x-intercept) and the K-parameter (square of the slope).

The instructions below describe the details of setting the 4145 todo MOSFET measurements and extracting parameters from the measureddata. The instructions assume that you are measuring an n-channelenhancement-mode MOSFET. The numbers used must be adjusted if you aremeasuring a PMOS or an depletion-mode device.

Note: In the below, there are buttons on the front panel and thereare 'soft keys' around the display. The function of the soft keyschanges as the display changes.

Step 1 - Obtaining i_D vs v_DS curves andextracting lambda

• Setting up and obtaining the data
  
  1. Go to the CHANNELS page using the CHAN button on the front panel. Push the soft key (MEM2 FET VDS-ID) that brings up the standard setup for a FET. This puts the 4155 into a configuration for measuring i_D vs. v_DS for FETs. Connect the drain, source, and gate of your MOSFET to the prescribed SMUs (SMU1 to source, SMU2 to drain, SMU3 to gate).
     
  2. Next, go to the MEASURE page (user either the front panel 'Meas' button or press the 'NEXT PAGE' soft key twice). to define the voltage and current ranges to be used. As a reasonable starting point, you might have the drain voltage range from 0 to 10V in 0.1V increments. The current compliance on the drain can be set to 25mA. Let the gate voltage step in 0.5V increment from 0 to 5V. The current compliance for the gate can be set to something small, like 1 µA.
     Note: The first push of the 'NEXT PAGE' softkey takes you to a page where you can define your own functions for plotting. You don't need this for the i_D - V_DS measurement, but we will make use of a function in the second part.
     Note 2: In entering the measurement parameters for the VAR1 (VDS) you should specify the start voltage, the stop voltage and the size of the step. The 4155 will calculate the number of steps to be used in the sweep. For VAR2 (VGS) you should provide the start voltage, the step size, and the number of steps. The 4155 will determine the final voltage. It seems mildly crazy to have to specify VAR1 and VAR2 in different fashions, but that's the way it is.
     Jump over to the 'Sweep' box and change the setting there to 'CONTINUE AT ANY'. This change is made by using the soft key in the upper right corner of the screen.
     The measurement page should look something like this:
     

     • VARIABLE	VAR1	VAR2
     UNIT NAME SWEEP MODE LIN/LOG START STOP STEP NO OF STEP COMPLIANCE POWER COMP	SMU2:HR VDS SINGLE LINEAR 0.0000 V 10.000 V 100.0mV 101 25.00mA OFF	SMU1:HR VG SINGLE LINEAR 0.0000 V 5.000 V 500.0mV 11 1.000uA OFF

     
     

     • TIMING HOLD TIME 0.0000 s DELAY TIME 0.0000 s

     •Sweep CONTINUE AT ANY

     
     • CONSTANT
     

     UNIT NAME MODE SOURCE COMPLIANCE

     - - - - - - - - - - - - - - - - - - - -

     - - - - - - - - - - - - - - - - - - - -

     - - - - - - - - - - - - - - - - - - - -

     
     
  3. Now advance to the DISPLAY page. (Use either the 'Display' front panel button or 'NEXT PAGE' softkey). You can have the measured data displayed in the form of a graph or as list of measured values. The default is the graph -- leave it that way for now. Set up the graphics plot so that v_DS ranges from 0 to 10V and i_D ranges from 0 to 10 mA. (You may have to come back to this page to resize the graph later if needed.)
     
  4. Advance to the GRAPH/LIST page. (Again, use either the front panel 'Graph/List' button or the 'NEXT PAGE' softkey.) This is the page where the measurements are done. To the right on the front panel is a button marked 'SINGLE'. Push this to have the 4155 to start sweeping through the voltages and measuring the currents. You should see lines sweeping across the graph. If everything is hooked up correctly, these should be the familiar family of MOSFET curves. If all the lines are overlapping on what appears zero current, you might have to rescale the plot. Do this by hitting the 'SCALE' soft key below the screen and then hitting the 'AUTO SCALE' soft key that appears on the right side of the screen.
     
  5. You might want to save the data to disk before proceeding.

     
     

• Extracting lambda

1. You can determine lambda for the MOSFET using the line features of the 4155. The sequence of steps is as follows:
   1. Push the MARKER/CURSOR softkey at the bottom of the screen to bring up the marker and cursor softkey controls on the side of the screen. (They may already be there.)
      
   2. Turn on the marker by pushing the 'MARKER' soft key. (It will switch from MARKER OFF to MARKER ON). The marker can be moved through the data using the dial. The marker starts at the first voltage of the first sweep and moves sequentially through all the data until it gets to the last voltage setting of the last sweep. You can make the marker hop directly to a new sweep by pushing the 'MARKER SKIP' softkey. Move the marker to the saturation region of one of the middle sweeps.
      
   3. Push the 'LINE' soft key at the bottom of the screen. This brings up the line control soft keys at the side of the screen.
      
   4. Push the 'CURSOR TO MARKER' soft key. A set of short cross-hairs will move to the point where the marker is located.
      
   5. Push the' 'LINE soft key on the side of the screen. (It will switch from LINE OFF to LINE ON.) This draws a vertical line through the point where the marker and cursor are located.
      
   6. Use the dial to move the cursor to a new point on the saturation part of the same curve.
      
   7. Push the 'CURSOR TO MARKER' soft key again. A second cursor is placed at the new marker location, and the line is redrawn so that it passes through the both the old cursor location and the new cursor location.
      

   The line that you have drawn should be right on top of the saturation region portion of the i_D vs v_DS curve. On the graph should be some information about the slope (grad) of the line and the x- and y-axis intercepts. You can use this info to determine lambda.

   You might want to measure lambda for several curves, (i.e. for different at least two different values of gate voltage) and take an average value.

Step 2 - extracting V_T and K

• Setting up and obtaining the data
  
  1. Use the Chan front panel button to step back to the CHANNELS page. You do not need to change the connections to the MOSFET terminals or the names or the modes, but you do need to make changes to the SMU FCTNs. Make the following changes:
     
     1. Change the function of SMU2 (VDS) to CONST.
     2. Change the function of SMU3 (VG) to VAR1.
        

     The CHANNELS page should now a table that looks something like the one below.

     MEASURE					STBY
     UNIT	VNAME	INAME	MODE	FCTN
     SMU1:HR SMU2:HR SMU3:HR SMU4:HR VSU1 VSU2 VMU1 VMU2	VS VDS VG VSUB	IS ID IG ISUB - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -	COMMON V V COMMON	CONST CONST VAR1 CONST - - - - - - - - - - - - - - - -

     
     

  2. Use the 'NEXT PAGE' soft key to step to the USER FUNCTION page. Here, you can enter your own function to to be measured. Of course, what we want is the square root of the drain current.
     Enter a user function in the first row of the table. You can call it SQRTID (or some such thing - the name is irrelevant), skip the units (also irrelevant), and type in SQRT(ID) in the expression column.
     

     Name	UNIT	DEFINITION
     SQRTID		SQRT(ID)

     
     
  3. Push the 'NEXT PAGE' soft key to go on to the MEASURE page. Set up the page to look something like the table below.

     • VARIABLE	VAR1	VAR2
     UNIT NAME SWEEP MODE LIN/LOG START STOP STEP NO OF STEP COMPLIANCE POWER COMP	SMU2:HR VG SINGLE LINEAR 0.0000 V 5.000 V 50.0mV 101 1.0000mA OFF

     
     • TIMING
     

     HOLD TIME	0.0000 s
     DELAY TIME	0.0000 s

     
     • CONSTANT
     

     UNIT NAME MODE SOURCE COMPLIANCE

     SMU2:HR VDS V 8.000 V 10.000mA

     - - - - - - - - - - - - - - - - - - - -

     - - - - - - - - - - - - - - - - - - - -

     
     

     You are programming the 4155 to sweep through a range of gate voltages while keeping the drain voltage constant. Using the numbers from the above table as an example, the gate voltage would sweep from 0 to 5V, while the drain voltage is held constant at 8V. Remember to set the compliances at reasonable values.

     Important measurement note: The values used above are purely for illustration. The numbers you use in your measurement will depend on the particular device your are measuring. The gate must sweep through a range that includes the threshold voltage. For instance, if you were measuring an depletion-mode NMOS transistor, where the threshold voltage is negative, the gate voltage range would have to start at value more negative than the threshold. Or, if measuring a PMOS transistor, all the voltages would have to be negative. Also, in setting the constant drain voltage, you must make certain that the MOSFET will stay in saturation. You will be safe as long as you choose the constant drain voltage to be bigger than any applied gate voltage. After taking a measurement, you might find it necessary to return to this page to adjust the settings, and then measure again.
     

  4. Move ahead to the DISPLAY page.
     Set up the graph so that the gate voltage will be on the x-axis and your user-defined function, SQRTID (or whatever), will be on the Y1 axis. These are entered using the soft keys. To find your SQRTID function, you must push the 'MORE 1/2' to go to the next menu of soft keys. SQRTID will show up there.
     • GRAPHICS

     X axis	Y1 axis	Y2 axis
     NAME SCALE MIN MAX	VG LINEAR 0.0000 V 5.000 V	SQRTID LINEAR 0.0000 1.0000

     
     
  5. Advance to the GRAPH/LIST page and push the SINGLE measurement button to take the measurement. It may be necessary use 'SCALE' and 'AUTO SCALE' to make the graph fit the data. You should see something like Fig. 1 above.
     
• Extracting V_T and K
  Once you have the graph in hand, determining the parameters is simply a matter of fitting a line to the sloping portion of the curve. Follow the procedure described above for creating a line and fitting it to a portion of the curve. The x-intercept and slope of the fitted line are given in the table at the bottom of the display.
  At this point you might want to save a copy of your data.
  Measurement note: For some MOSFETs the plot of the square-root of i_D is sublinear (meaning that it is not a straight line, but bends down at higher gate voltages). This is an indicator that the simple level 1 model for the MOSFET will probably not provide a very good description of the real MOSFET's behavior. When trying to find the threshold voltage for a MOSFET that displays this type of behavior, try to fit the straight line at lower gate voltages - just slightly above threshold. If you use higher gate voltages - in the region where the curve is bending - the extracted threshold voltage will be unreasonably low and perhaps even negative.

Saving data todisk

K4145 Mosfet Equivalent

You can save your 4155 data on a PC formatted floppy and then makeplots using EXCEL (or other graphing program).

From the Graph/List: Graph page (the one with your curvesplotted)

1. Insert a disk into the drive.
   
2. Press the Graph/List button to display the data in a table.
   
3. Press the Spreadsheet soft key to enter the save mode.
   
4. Enter a name for your data file (do not use an extension, .txt will be appended automatically by the 4155)
   
5. Make sure the OUTPUT DATA indicates from 1 to MAX, otherwise press the ALL softkey. This ensures that all data points will be saved. Alternatively, you can use this feature to save only a portion of your data.
   
6. Arrow over to delimiter and enter the delimiter you want. MS Excel will work with any, so you can leave it SPACE if you want.
   
7. Press the 'EXECUTE' soft key to save the data.

Note: If the data includes multiple sweeps, the 4155 will stillsave them in two columns. Each set of data will follow the last asdepicted below:

X(sweep1) Y(sweep1)

. .

. .

X(sweep2) Y(sweep2)

. .

. .

and so on. So you may need to massage the columns for Excel toconsider them as multiple series.

K4145 Mosfet Datasheet

K4145 Datasheet PDF - NEC

Transistor Mosfet K4145

K4145 Mosfet Pinout

Electronic Components Distributor

Featured Datasheets