This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Pratices: Practice 1 : ib hie hfe ib 1 / hoe VCE hre h parameters Definition on individual group Unit h ie • The input impedance of the transistor (corresponding to the emitter resistance r e ) • h ie = B BE ΔI ΔV at I B – V BE graph Ω h re • Represents the dependence of the transistor's I B – V BE curve on the value of V CE . It is usually very small and is often neglected (assumed to be zero) • h re = CE BE ΔV ΔV at V CE – V BE graph No unit h oe • The output impedance of transistor. This term is usually specified as an admittance and has to be inverted to convert it to an impedance • h oe = CE C ΔV ΔI at I C – V CE graph Siemens h fe • The current-gain of the transistor. This parameter is often specified as h FE or the DC current-gain ( β DC ) in datasheets • h fe = B C ΔI ΔI at I C – I B graph No unit 1 / 6 Practice 2 : vout hie RC hfe ib ib vin ( 29 C T CQ C e fe e C fe ie C fe ie b C b fe in out v C b fe out ie b in R V I R r h r R h h R h h i R...
View Full Document