1 / 10

Ebers -Moll for computer/hand use

Ebers -Moll for computer/hand use . IC vs. VBE; VCS > 4 VT. NPN/ PNP – rce = 1/ gce. npn. pnp. I C vs. V CE. Early Voltage – r ce = VA/I CQ gm = I CQ /nVt rbe = /gm = nVt / I BQ Cbe = TF/rbe. Small Signal Model. I C vs. V VE - I C vs. V CE; . BJT Model.

tonya
Download Presentation

Ebers -Moll for computer/hand use

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ebers-Moll for computer/hand use

  2. IC vs. VBE; VCS > 4 VT

  3. NPN/ PNP – rce = 1/gce npn pnp

  4. IC vs. VCE Early Voltage – rce = VA/ICQ gm = ICQ/nVt rbe = /gm =nVt/IBQ Cbe = TF/rbe Small Signal Model

  5. IC vs. VVE - IC vs. VCE; BJT Model CE Amplification ckt

  6. Q pt Bias Stabilization Select IE RE = 4-5xVBEQ= 2.4V to 3V Ensures stability across process and temperature Given : ICQ = 2.5 mA, VCEQ = 6V, b = 100, & IBQ = 25uA, VA = 50 V, VCC = 10 V BIAS RESISTORS: RB1 = 14 K ohms, RB2 = 6 K ohms, & RE = 2.4V/2.5mA  1 K ohms Small Signal result : rbe = nVt/IBQ = 26mV/25uA  1 K ohms, gm = ICQ /nVt  40 x 2.5mS = 100 mS, rce =VA/ICQ = 50/2.5mA = 20 Kohm

  7. f1 or High Pass Bias Considerations FindCc1, Cc2, & CE Using Amplification Mid-Band BIAS RESISTORS: RB1 = 14 K ohms, RB2 = 6 K ohms, & RE 1 K ohms Small Signal result : rbe = nVt/IBQ = 26mV/25uA  1 K ohms, gm = ICQ /nVt  40 x 2.5mS = 100 mS, rce =VA/ICQ = 50/2.5mA = 20 Kohm CE- Amplification

  8. Mid-band and f2gain Cc1, Cc2, and CE were selected to be short circuits at mid-band and higher Resulting in the following small signal model CE- Amplification Mid-Band Output Eq Input Eq Input Eq Simplified

  9. f2 Considerations Amplification CE- Amplification At midband A = CL and Cbe neglected At f2 A = solve for poles For a midband gain of -10; RC = -10/-gm = 10/.1mS = 100 ohms;

  10. Bias Check For a midband gain of -10; RC = -10/-gm = 10/.1mS = 100 ohms; RC sets gain RESISTORS: RC = 100 ohms, RB1 = 14 K ohms, RB2 = 6 K ohms, & RE 1 K ohms; Stabilzes Qpt, RB1 AND RB2 Set VBB. • VCE = VCC – IC{RC+ RE} = 10 – 2.5mAx1.1K ohms = 7.25V • VCE = 7.25V • VRE = 2.5V = Emitter voltage • VB = 0.65V + 2.5V = 3.15V = Base Voltage • ZL = O-scope probe in lab • CC1 = ??? • CC2 = ??? • CE = ???

More Related