125 ohms. 1. Select Y for Input Type. 2. Enter the values 75+12*i, 75 -12*i, 125 for ZZA_, ZZB_ and ZZC_. 3. Press to calculate ZZ1_, ZZ2_ and ZZ3_.

Input Parameters

The computation results are:

Calculated Output

ZZ1_: 34.0909 - 5.45455i ZZ2_: 34.0909 + 5.45455i ZZ3_: 20.9782

4.2 Balanced Wye Load

A balanced Wye load refers to three identical impedance loads connected in a Wye configuration. The voltage V12_ represents the line voltage from line 1 to line 2 and is used as the reference voltage throughout this Wye network. The voltages across lines 2 and 3, and across 3 and 1 have the same magnitude as V12_, but are out of phase by 120 and 120 respectively. The software computes the currents I1_, I2_, and I3_ in each leg of the Wye network, the line to neutral voltage in each phase V1N_, V2N_, and V3N_, the power dissipated in each phase P, and the wattmeter readings W12 and W13 connected to the circuit as shown in the Fig 4-3.

Input Fields

Input Type: V12_: (Reference Voltage in V across lines 1 and 2) (Phase Impedance in ) Enter a real or complex number, variable name, or algebraic expression of defined terms. Enter a real or complex number, variable name, or algebraic expression of defined terms.
V23_: V31_: V1N_: V2N_: V3N_: I1_: I2_: I3_: P: W12: W13: (Voltage in V across lines 2 and 3) (Voltage in V across lines 3 and 1) (Voltage in V across 1N) (Voltage in V across 2N) (Voltage in V across 3N) (Line Current 1 in A) (Line Current 2 in A) (Line Current 3 in A) (Phase Power in W) (Wattmeter reading in W across lines 1 and 2) (Wattmeter reading in W across lines 1 and 3) A real, complex number, or variable name. A real, complex number, or variable name. A real, complex number, or variable name. A real, complex number, or variable name. A real, complex number, or variable name. A real, complex number, or variable name. A real, complex number, or variable name. A real, complex number, or variable name. A real number or variable name. A real number. A real number.

I rb (hie) ICIS

Two-Port Network Can be added only in cascade connection. Choose z, y, h, g, a, or b for Input Parameters, and enter values for.11,.12,.21, and.22.
Zin_: I2/V1_: I2/I1_: Pout/Pin: V2/V1_: V2/I1_: (Input Impedance in ohms) Returns a real or complex number, variable name or algebraic expression. (Forward Transfer Admittance Returns a real or complex number, variable name or algebraic in Siemens) expression. (Current Transfer Ratio) Returns a real or complex number, variable name or algebraic expression. (Real Power Gain) Returns a real or complex number, variable name or algebraic expression. (Forward Voltage Transfer Ratio) Returns a real or complex number, variable name or algebraic expression. (Forward Transfer Impedance Returns a real or complex number, variable name or algebraic in ohms) expression.
5.2 Using the Ladder Network
General instructions for entering the elements and computing the parameters of a ladder network. 1. The initial screen prompts the user for entry of values for Frequency and Load. 2. Build the ladder by adding elements to it. Press to insert the first element. Choose an element type and press. Enter the appropriate values. Press to update the ladder with the new element just added. A second press of the key computes the electrical performance of the circuit. 3. New elements can be added or inserted by moving the highlight bar to the location desired and pressing. The new element will appear after the a highlighted element. 4. A circuit element can be deleted from the ladder by moving the highlight bar to the element and pressing. 5. Press to compute the overall ladder network parameters. 6. Previously calculated results are not automatically updated for new element entries; the user must press to re-solve for the circuit parameters for a new circuit configuration.

Example 5.1

What is the input impedance of the circuit shown below in Fig. 5.1 at 1 MHz and 10 MHz?

10E-6 H 50 pF

Load 50

Element 4

Element 3

Element 2

Element 1
Fig. 5.1 Ladder Network Example
Entering Load and Frequency
Partial list of Element Choices
Typical Edit Screen for an Element
List of all the Ladder Components

Output Screen at 1 MHz.

Output Screen at 10 MHz

1. 2. 3.

Enter 1E6 for Frequency. Enter 50 for Load. Press to add the first element and move the highlight bar in the pull down menu to Capacitor and press to display the input screen for the Capacitor. Select Parallel for Configuration of the capacitor and enter the value 50E-12 for C. Press to accept the element data and press to return a listing of the Ladder Network. Move the highlight bar to 1: Capacitor and press to enter the second element in this circuit. Move the highlight bar to Inductor to display the input screen for the new element. Choose Series for Config and enter the value 10E-6 for L. Press to accept the value and press to update the ladder. Enter the remaining two elements: a 100 pF (100E-12) capacitor in parallel and a 50 ohm resistor in series. Press to calculate the results displayed in the output screen as shown above. To delete an element from the network, highlight it and press , the delete key.

n: Q1: Gc: Bc: (Primary to secondary turns ratio) (Reactive power in W) (Primary core conductance in S) (Primary core susceptance in S) Returns a real number or algebraic expression. Returns a real number or algebraic expression. Returns a real number or algebraic expression. Returns a real number or algebraic expression.

Example 10.1

Perform an open circuit test on the primary side of a transformer using the following data: The input to the primary coils with the secondary side open is 110 volts, and a current of 1 ampere and a power of 45 watts. The secondary open circuit voltage is 440 volts. Find the circuit parameters of the transformer.
EE Pro for TI -89, 92 Plus Analysis - Transformer Calculations
Enter the values 110 for V1 and 440 for V2. Enter 1 for I1 and 45 for PP1. Press to calculate and display the results, as shown above.

10.2 Short Circuit Test

Short circuit tests are often a quick method used to determine the winding impedance of a transformer and are usually reported at rated kVA values. This test consists of placing a short circuit across the secondary windings and applying a small primary voltage to measure the secondary current, and power supplied to the transformer. The calculated circuit parameters (i.e., resistance and reactance of primary and secondary coils) are based on the assumption that the heat dissipation in the primary and secondary windings are equal.
V1: I2: PP1: kVA: V1R: (Primary RMS Voltage in V) (Secondary RMS Current in A) (Primary Real Power in W) (kVA rating in kVA) (Primary Voltage Rating in V) Magnitude only. A real number, variable name, or algebraic expression of defined terms. Magnitude only. A real number, variable name, or algebraic expression of defined terms. A real number, variable name, or algebraic expression of defined terms. A real number, variable name, or algebraic expression of defined terms. A real number, variable name, or algebraic expression of defined terms.
n: QP1: RR1: RR2: XX1: XX2: (Primary to secondary turns ratio) (Primary Reactive Power in W) (Primary Resistance in ) (Secondary Resistance in ) (Primary Reactance in ) (Secondary Reactance in ) Returns a real number or algebraic expression. Returns a real number or algebraic expression. Returns a real number or algebraic expression. Returns a real number or algebraic expression. Returns a real number or algebraic expression. Returns a real number or algebraic expression.

Example 13.1

What is the value of erf(.25)?
1. 2. 3. Enter.25 for X. Choose ERF in Func. Press to calculate Result.
EE Pro for TI-89, 92 Plus Analysis - Error Functions

Chapter 14

Payback Period Net Present Value

Capital Budgeting

Internal Rate of Return Profitability Index
This chapter covers the four basic measures of capital budgeting:
14.1 Using Capital Budgeting
This section performs analysis of capital expenditure for a project and compares projects against one another. Four measures of capital budgeting are included in this section: Payback period (Payback), Net Present Value (NPV), Internal Rate of Return (IRR), and Profitability Index (PI). This module provides the capability of entering, storing and editing capital expenditures for nine different projects. The following equations are used in calculations:

NPV =

CFt CFt = 0 (1 + k )t

Eq. 14.1.1

(1 + IRR)

CFt = 0 = 0

Eq. 14.1.2

(1 + k )

CFt = 0

Eq. 14.1.3

CFt: Cash Flow at time t (usually years). Payback: The number of time periods (usually years) it takes a firm to recover its original investment. NPV: The present values of all future cash flows, discounted at the selected rate, minus the cost of the investment. IRR: The discount rate that equates the present value of expected cash flows to the initial cost of the project. PI: The present value of the future cash flows, discounted at the selected rate, over the initial cash outlay.
Project: k: Payback: NPV: IRR: PI: (Project) (Discount Rate per Period in %) (Payback Period) (Net Present Value) (Internal Rate of Return) (Profitability Index) Press to select one of nine unique projects or edit the current name of the project by pressing for Cash option. Enter a real number. Returns a real number. Returns a real number. Returns a real number (%). Returns a real number.
EE Pro for TI - 89, 92 Plus Analysis - Capital Budgeting

Multiple Graphs

Activation of this feature enables the overlay of each successive graph (projects) on the same axis. Press to activate. Press to activate.

2. Enter known values for each variable using the tool bar to designate units. Press to compute the results.
3. If multiple solution exists, a dialogue box will appear requesting the user to enter the number of a solution to view.
Solution 1: To view another solution, press to re calculation and enter the number. of another solution to be viewed.
Solution 2: Enter a new number for each solve to display a series of. multiple solutions.

15.5 Partial Solutions

"One partial useable solution found." or "Multiple partial solutions found." will be displayed in the status line if values for one or more variables in the selected equation set cannot be computed. This situation can occur if there are more unknowns than equations in the selected set, the entered values do not form consistent relationships with
the selected equations, or if the selected equations do not establish a closed form relationship between all of the entered values and the unknowns. In such a case, only the calculated variables will be displayed.
Press to select all of the
If there are more unknowns than selected equations or relationships between variables are not established from the selected equations.
.a partial solution will be displayed if one or more of the unknown variables are able to be computed from the entered inputs.
equations in Resistive Formulas.

15.6 Copy/Paste

A computed result and its expressed units can be copied and pasted to the HOME screen or any other location of EEPro using :Tools-5:Copy key sequence to copy a value and :Tools-6:Paste to paste the item in any appropriate context of the TI system.

15.7 Graphing a Function

The relationship between two variables in an equation can be graphed on a real number scale if the other variables in the equation are defined. After solving an equation, or entering values for the non x,y variables in the equation to be plotted, press /Graph to display the graph settings. Highlight Eq: and press to select the equation from the list to graph. Use the same steps as above to select the independent and dependent variables (Indep: and Depnd:) from the equation. Note: all pre-existing values stored in the variables used for Indep: and Depnd: will be cleared when the graphing function is executed. The graphing unit scale for each variable reflect the settings in the Equations section of EEPro. Scrolling down the list, specify the graphing ranges for the x and y variables, whether to graph in full or split screen modes, automatically scale the graph to fit the viewing area, and label the graph. Press to graph the function. Once the graph command has been executed, EEPro will open a second window to display the plot. All of the TI graphing features are available and are displayed in the toolbar, including Zoom , Trace , Math , etc. The Math feature is extremely useful for determining critical function values such as intercepts, inflections, derivatives, integrals, etc. Peak performance, damped resonance and decay functions are able to be evaluated using this tool. If the split-screen graphing mode is activated, the user can toggle between the EEPro graph dialogue display and the TI graph by pressing 2 O. If the full-screen graphing mode is activated, the user can switch between EEPro and the graph by pressing O 4:Graph or A:EEPro. *Before graphing an equation, be sure to specify values for variables in an equation which are not going to be used as x and y variables.

EEPro displays a notice if the nsolve routine is used.
The user can enter a value for for the unknown and designate it as a guessed value to accelerate the nsolve convergence process.
15.11 Why can't I compute a solution?
If a solution is unable to be computed for an entered problem, you might check the following: 1. 2. 3. Are there at least as many equations selected as there are unknown parameters? Are the entered values or units for the known parameters reasonable for a specific case? Are the selected equations consistent in describing a particular case (for example, the choice of certain equations used in the calculation of diode properties depends on whether the donor density of the doping substance Nd, exceeds the acceptor density, Na in the Semiconductors section of Solid State)
15.12 Care in choosing a consistent set of equations
The success of the equation solver in generating a useful solution, or a solution at all, is strongly dependent on the user's insight into the problem and care in choosing equations which describe consistent relationships between the parameters. The following steps are suggested: Read the description of each set of equations in a topic to determine which subset of equations in a series are compatible and consistent in describing a particular case. Select the equations from a subset which describe the relationships between all of the known and unknown parameters. As a rule of thumb, select as many equations from the subset as there are unknowns to avoid redundancy or over-specification. The equations have been researched from a variety of sources and use slightly different approximation techniques. Over-specification (selecting too many equations) may lead to an inability of the equation solver to resolve slight numerical differences in different empirical methods of calculating values for the same variable.
15.13 Notes for the advanced user in troubleshooting calculations
When there are no solutions possible, EEPro provides important clues via key variables eeinput, eeprob, eeans, and eeanstyp. These variables are defined during the equation setup process by the built-in multiple equation solver. EEPro saves a copy of the problem, its inputs, its outputs, and a characterization of the type of solution in the user variables eeprob, eeinput, eeans, and eeanstyp. For the developer who is curious to know exactly how the problem was entered into the multiple equation solver, or about what the multiple equation solver returned, and to examine relevant strings. The contents of these variables may be viewed by using VAR-LINK and examining these variables in the current session. Press (2 followed by |), scroll to the variable name in the current folder and press to view the contents of the variable. The string may be recalled to the author line of the home screen, modified and re-executed, if desired.

Variables

A complete list of all the variables used, a brief description and applicable base unit is given below. Variable A G I Il Is len P Pmax R Rl Rlm RR1 RR2 Rs T1 T2 V Vl Vs Description Area Conductance Current Load current Current source Length Power Maximum power in load Resistance Load resistance Match load resistance Resistance, T1 Resistance, T2 Source resistance Temperature 1 Temperature 2 Voltage Load voltage Source voltage Temperature coefficient Resistivity Conductivity Unit m2 S A A A m W W K K V V V 1/K *m S/m
EE Pro for TI - 89, 92 Plus Equations - Resistive Circuits

16.1 Resistance Formulas

Four equations in this topic represent the basic relationship between resistance and conductance. The first equation links the resistance R of a bar with a length len and a uniform crosssectional area A with a resistivity. The second equation defines the conductance G of the same bar in terms of conductivity , len and A. The third and fourth equations show the reciprocity of conductance G resistance R, resistivity and conductivity.

len A

Eq. 16.1.1

A len 1 G= R 1 =

.45_cm2. Compute the its resistance and conductance.
Eq. 16.1.2 Eq. 16.1.3 Eq. 16.1.4
Example 16.1 - A copper wire 1500_m long has a resistivity of 6.5_ohm*cm and a cross sectional area of
Solution - Upon examining the problem, two choices are noted. Equations 16.1.1, 16.1.2 and 16.1.4 or
16.1.1 and 16.1.3 can be used to solve the problem. The second choice was made here. Press to display the input screen, enter all the known variables and press to solve the selected equation set. The computed results are shown in the screen display shown here.

Entered Values

Computed results
-PQYP8CTKCDNGUNGPAOAQJOEO#AEO %QORWVGF4GUWNVU4'AQJO)'AUKGOGPU

16.2 Ohms Law and Power

The fundamental relationships between voltage, current and power are presented in this section. The first equation is the classic Ohm's Law, computes the voltage V in terms of the current I, and the resistance R. The next four equations describe the relationship between power dissipation P, voltage V, current I, resistance R and conductance G in a variety of alternate forms. The final equation represents the reciprocity between resistance R and conductance G.
V = I R P =V I P = I2 R P= V2 R
Eq. 16.2.1 Eq. 16.2.2 Eq. 16.2.3 Eq. 16.2.4

P = V 2 G R= 1 G

Eq. 16.2.5 Eq. 16.2.6
Example 16.2 - A 4.7_kohm load carries a current of 275_ma. Calculate the voltage across the load, power dissipated and load conductance.
Solution - Upon examining the problem, several choices are noted. Either Equations 16.2.1, 16.2.2 and 16.2.6, or 16.2.2, 16.2.3 and 16.2.5 or 16.2.2, 16.2.3 and 16.2.6 or 16.2.1, 16.2.2 and 16.2.5 or all the equations. Choose the last option, press to open the input screen, enter all the known variables and press to solve.

24.2 Balanced Wye Network
These equations describe the relationship for a Balanced Wye Network. The first equation computes the line voltage VL from the phase voltage Vp. The second equation calculates the line current IL from the phase current Ip. The power/phase P, is defined in terms of Vp, Ip and phase delay. The last two equations are used to estimate the total power PT delivered to the system from the parameters VL, IL or Vp and Ip.
VL = 3 Vp IL = Ip P = Vp Ip cos

Eq. 24.2.1 Eq. 24.2.2

Eq. 24.2.3 Eq. 24.2.4 Eq. 24.2.5
Example 24.2 - Using the known parameters in the previous example for the Balanced Network, find the phase
current, power, total power and line voltage.
Solution - All of the equations are needed to compute the solution. Press to display the input screen,
enter all the known variables and press to solve the equation set. The computed results are shown in the screen display above.
-PQYP8CTKCDNGU+.A#ATCF8RA8 %QORWVGF4GUWNVU+RA#2A926A98.A8

24.3 Power Measurements

These three equations for a two-watt meter connection are used to measure the total power of a balanced network. The first two equations determine the watt meter readings W1 and W2 are expressed from the line current IL, line voltage VL, and phase delay between the voltage and the current. The final equation represents the total power, PT, delivered to the three-phase load.

24.3.1

FG IJ H 6K F I W 2 = VL IL cosG J H 6K PT = 3 VL IL cosb g

W1 = VL IL cos +

Eq. 24.3.2 Eq. 24.3.3
Example 24.3 - Given a line voltage of 110 V and a line current of 25 A and a phase angle of 0.1 rad, find the wattmeter readings in a 2 wattmeter meter system.
Solution - All of the equations are needed to compute the solution for this problem. Press to display the input screen, enter all the known variables and press to solve the equation set. The computed results are shown in the screen display above.

Solution - Use the second equation to solve this problem. Select this with the highlight bar and press. Press to display the input screen, enter all the known variables and press to solve the selected equation. The computed result is shown in the screen display above.
-PQYP8CTKCDNGU %QORWVGF4GUWNVU 'CA8+.A#4CA4UA 8VA8
31.6 Separately-Excited DC Motor
These equations form the working foundation for a separately excited motor. The first equation calculates the field voltage Vf in terms of the field current IIf and field coil resistance Rf.

Vf = Rf IIf

Eq. 31.6.1
The second equation computes the terminal voltage Vt in terms of the machine constant K, magnetic flux , mechanical radian frequency m, armature current Ia, and armature resistance Ra.

Vt = K m + Ra Ia

The load torque TL, in the third equation is defined in terms of K, , Ia and Tloss.

Eq. 31.6.2

TL = K Ia Tloss

Eq. 31.6.3

Ea, the back emf induced in the rotor, is calculated by the next equation. Torque T links with K, , and Ia.

Ea = K m T = K Ia

Eq. 31.6.4 Eq. 31.6.5
The reciprocal power relationship between m and by the inverse quadratic relationship. The next set of equations show the relationship between T, the torque lost due to friction Tloss and the torque load TL. The last equation in this set shows relationship of power with torque T and angular velocity m.

Vt Ra T 2 K K

Eq. 31.6.6

T = Tloss + TL P = T m

Eq. 31.6.7 Eq. 31.6.8
Example 31.6 - Find the terminal voltage, field current and machine constant for a motor with an armature
current 0.5 A and resistance of 100 rotating at an angular velocity of 31 r/s. The back emf is 29 V. The field is driven by a 15 V source driving a 50 load. The flux available in the armature is 2.4 Wb.
Solution - Solve the first, second, fourth and fifth equations. Select these by highlighting and pressing. Press to display the input screen, enter all the known variables and press to solve the selected equation set. The computed results are shown in the screen display above.

'CA8+CA#A9D4CA4HA8HA8 OATU ++HAO#-6A0O8VA8

31.7 DC Shunt Motor

These seven equations describe the principal characteristics of a DC shunt motor. The first equation expresses the terminal voltage Vt in terms of the field current IIf and field resistance Rf along with the external field resistance Re. The second equation defines the terminal voltage Vt in terms of the back emf (expressed in terms of the machine constant K, flux swept , and angular velocity m) and the IR drop in the armature circuit.
Vt = Re + Rf IIf Vt = K m + Ra Ia

Eq. 31.7.1 Eq. 31.7.2

The third equation refers to the torque available at the load TL due to the current Ia in the armature minus the loss of torque Tloss due to friction and other reasons.

Eq. 31.7.3

The fourth equation gives the definitive relationship between the back emf Ea, K, and m.

Eq. 31.7.4

The next equation displays the reciprocal quadratic relationship between m, Vt, K, , armature resistance Ra, adjustable resistance Rd and T.

Ra + Rd T Vt 2 K K

Eq. 31.7.5
The last two equations compute torque T in terms of Tloss, load torque TL, flux , Ia, and K.

T = Tloss + TL

Eq. 31.7.6 Eq. 31.7.7

T = K Ia

2.4 Wb.
Example 31.7 - Find the back emf for a motor with a machine constant of 2.1, rotating at 62 rad/s in a flux of
Solution - Use the fourth equation to solve this problem. Select the equation with the cursor bar and press. Press to display the input screen, enter all the known variables and press to solve the selected equation. The computed result is shown in the screen display above.
-PQYP8CTKCDNGU %QORWVGF4GUWNV -A9DOATU 'CA8

31.8 DC Series Motor

These eight equations describe the performance characteristics of a series DC motor. The first equation links the terminal voltage Vt to the back emf (Ea defined by the third equation) and the IR drop through the armature due to armature resistance Ra, adjustable resistance Rd, and series resistance Rs. The second equation calculates the load torque TL with the machine constant K, flux , load current IL, and the torque loss Tloss.

EE Pro for TI-89, 92 Plus Appendix A - Frequently Asked Questions
A. EEPro automatically stores its variables in the current folder specified by the user in 3 or the HOME screens. The current folder name is displayed in the lower left corner of the screen (default is Main). To create a new folder to store values for a particular session of EEPro, press :/TOOLS, :/NEW and type the name of the new folder (see Chapter 5 of the TI-89 Guidebook for the complete details of creating and managing folders). There are several ways to display or recall a value: The contents of variables in any folder can be displayed using the , moving the cursor to the variable name and pressing to display the contents of a particular variable. Variables in a current folder can be recalled in the HOME screen by typing the variable name. Finally, values and units can be copied and recalled using the /Tools 5:COPY and 6:PASTE feature. All inputs and calculated results from Analysis and Equations section are saved as variable names. Previously calculated, or entered values for variables in a folder are replaced when equations are solved using new values for inputs. Q. Why is it that some of the values of variables saved earlier are cleared when I graph an equation or analysis function which uses the variable name(s)? A. When an equation or analysis function is graphed, EEPro creates a function for the TI grapher which expresses the dependent variable in terms of the independent variable. This function is stored under the variable name pro(x). When the EEPros equation grapher is executed, values are inserted into the independent variable for pro(x) and values for the dependent value are calculated. Whatever values which previously existed in either of the dependent and independent variables in the current folder are cleared. To preserve data under variable names which may conflict with EEPros variables, run EEPro in a separate folder using the guidelines above. Q. An item which is supposed to be displayed in a menu doesnt appear. A. Some menus have more than eight items. If an arrow appears next to the digit 8, use the arrow key D to scroll the menu and view the remaining topics or press 2 D jump to the bottom of the menu. Q. Is there a help section in the software? A. There is a short series (slides) of general hints which can be accessed from the main screen of EEPro under /Info. A different message appears each time is pressed. Weve attempted to keep most of the explanation of certain topics to the manual in an effort to keep the software compact. Consult the chapter corresponding to the appropriate section of the software. If your are still in need of clarification, contact Texas Instruments (contact information in the Warranty and Technical Support section of the manual) A compiled list of the received questions and answers will be posted periodically on the da Vinci website. http://www.dvtg.com/faq/eepro

16. Cohen and Taylor, Rev. Modern Physics, Vol. 59, No. 4, October 1987, pp. 1139-1145
17. Sze, Simon, Physics of Semiconductors, John Wiley and Son, New Jersey, 1981 18. Mueller, Richard S., and Kamins, Theodore I., Device Electronics for Integrated Circuits, 2nd Edition, John Wiley and Son, New jersey, 1986 19. Hodges, David A., Jackson, Horace A., Analysis of Digital Integrated Circuits, McGraw-Hill, New York, 1988
EE Pro for TI - 89, 92 Plus Appendix C: Bibliography
20. Elmasry, Mohamed I., Editor, Digital MOS Integrated Circuits, IEEE Press, New York, 1981 21. Kuo, Benjamin C., Automatic Control Systems, Prentice Hall, New jersey, 1991 22. Stevenson Jr., William D., Elements of Power Systems Analysis, McGraw-Hill International, New York, 1982 23. Wildi, Theodore, Electrical Power Technology, John Wiley and Son, New Jersey, 1981 24. Yarborough, Raymond B., Electrical Engineering Reference Manual, Professional Publications, Belmont, CA 1990 25. Schroeder, Dieter K., Advanced MOS Devices, Addison Wesley, Reading MA 1987 26. Neudeck, Gerold W., The PN Junction Diode, Addison Wesley, Reading MA 1983 27. Pierret, Robert F., Semiconductor Fundamentals, Addison Wesley, Reading MA 1983 28. Pierret, Robert F., Field Effect Devices, Addison Wesley, Reading MA 1983 29. Neudeck, Gerold W., The Bipolar Junction Transistor, Addison Wesley, Reading MA 1983 30. Irwin, David J., Engineering Circuit Analysis, McGraw-Hill, New York, 1987
Appendix D: TI-89 & TI-92 PlusKeystroke and Display Differences
D.1 Display Property Differences between the TI-89 and TI-92 Plus
The complete display specifications for both the TI-89 and TI-92 Plus calculators are displayed below.
Table D-1 TI-89 and TI-92 Plus display specifications.
Property Display size Pixel Aspect ratio Full Screen Horizontal Split Screen TI-x 100 1.characters/line 10 lines 156 x 39 pixels 25 characters 4 lines 77 x 80 pixels 12 characters 10 lines Not supported Not supported Not supported Not supported 16 pixel rows TI-92 Plus 240 x 128 1.characters/line 13 Lines 236 x 51 pixels 39 characters, 6 lines 117 x 104 pixels 19 characters, 13 lines 236 x 33 pixels 39 characters, 4 lines 236 x 69 pixels 39 characters, 8 lines 77 x 104 pixels 12 characters, 13 lines 157 x 104 pixels 26 characters, 13 lines 20 pixel row

Vertical Split Screen

Vertical Split Screen (1/3rd) Vertical Split screen (2/3rd) Horizontal Split Screen (1/3rd) Horizontal Split Screen (2/3rd) Key legends

E.3 Equation Messages

If a value is entered that is inconsistent with the expected data type, an error dialog will appear which lists the entry name, the description, and the expected data type(s), and the expected units.
If an error occurs during a computation that involves temperature, "temp conversion err" or "deg/watt conversion err" will be displayed. When solving equation sets, several messages can be displayed. These messages include: One or more equations has no unknowns.. This message occurs if one or more of the selected equations in a solution set has all of its variables defined by the user. This can be remedied by pressing N, deselecting the equation(s) where all of the variables are defined and resolving the solution set by pressing twice. To determine which equation has all of its variables defined, press N to view the equations, select an equation in question by highlighting the equation and pressing , and pressing to view the list of variables. A next to a variable indicates a value has been specified for that variable by the user. If all of the variables in an equation are marked with a , no unknown variables exist for that equation. This equation should not be included in the solution set. Press N to view the list of equations. Select the equations to be solved, excluding the equation with no unknowns, and press twice to resolve the set of equations.
"Unable to find a solution in the time allowed. Examine variables eeinput and eeprob to see the exact statement of the problem. EE\xB7Pro sets Exact/Approx mode to AUTO during solve. No equations have been selected. Please select either a single equation to solve by itself, or several equations to solve simultaneously. "Too many unknowns to finish solving"-generally occurs if the number of equations is less than the number of unknowns "It may take a long time to find a complete solution, if one can be found at all. You may abort the calculation at any time by pressing the ON key." -this occurs if there are many unknowns or multiple solutions. No input values provided. occurs if none of the variables have values designated when solving an equation set. "The nsolve command will be used. The existing value for the unknown, if any, will be used as an initial guess." The nsolve function is used when a single unknown exists in the equation and the unknown variable is an input in a user defined function (an example is the error function erf in Semiconductor Basics of Solid State or the eegalv in Wheatstone Bridge in Meters and Bridges). The nsolve function will not generate multiple solutions and the solution which nsolve converges upon may not be unique. It may be possible to find a solution starting from a different initial guess. To specify an initial guess, enter a value for the unknown and then use F5:Opts/7:Want to designate it as the variable to solve for. More information on the differences between the solve, nsolve and csolve functions is listed in the TI-89 manual. "One complete useable solution found." All of the unknown variables were able to be solved in the selected equations. "One partial useable solution found." Only some of the variables in the selected equations were able to be solved. Multiple complete useable solns found." One or more variables in the selected equations have two possible values "Multiple partial useable solns found." One or more variables in the selected equations have two possible values, however not all of the unknown variables were able to be solved.