EE 105, Spring 1994 Midterm 2: Transistor Parameters and Circuits, Exams of Microelectronic Circuits

Download EE 105, Spring 1994 Midterm 2: Transistor Parameters and Circuits and more Exams Microelectronic Circuits in PDF only on Docsity! EE 105, Spring 1994 Midterm #2 professor Howe Default bipolar transistor parameters: npn: &#223n = 100, VAn = 50V, ISb = 10-16, VTh = 25 mV pnp: &#223n = 50, VAn = 25V, ISb = 10-16, VTh = 25 mV Default MOS transistor parameters: NMOS: &#181n C'ox= 50 &#181AV-2, [LAMBDA]n= 0.02 V-1, VTn= 1V. PMOS: &#181p C'ox= 25 &#181AV-2, [LAMBDA]p= 0.02 V-1, VTp= -1V. Problem #1a Assuming that transistor M2 is saturated, what is the numerical value of Io, the output current of this simple current source. Problem #1b[4 pts] Assuming that Vo = 2 V, find the numerical value of Roc, the output resistance of this simple current source. If you couldn't solve part(a), you may assume that the saturation current Io = 50 uA, which is not the correct answer to (a). Problem #1c[7 pts] Plot the output current Io versus the output voltage Vo(which should vary from 0 to 3.5 V). There is no need for accuracy in the triode region; however, the numerical value for the saturation current and the boundary between the triode and the saturation region should be correct. EE 105, Midterm #2, Spring 1994 EE 105, Spring 1994 Midterm #2 professor Howe(e.g., Professor J. Wawrzynek) 1 Problem #1d[3 pts] For the new current source below, we would like to keep the same value for Io in saturation as you found in part(a). In order to do this, we must change the width-to-length ratio of M1. Note that the reference current Iref is unchanged. Find the numerical value of the width of M1, given that its length is L1=2um. Again, you an assume for this part that Io=50uA, in case you were not able to solve part (a). Problem #1e[3 pts] What is the numerical value of the output resistance of the new current souce? Again, you can assume for this part that Io=50uA, in case you were not able to solve part (a). Problem #2a[3 pts] Find the numerical value of VCE for each transistor. Note that the DC output voltage VL = 0V. You can assume that the transistors are forward-active and that VBE = 0.7 V. EE 105, Midterm #2, Spring 1994 Problem #1c[7 pts] 2