{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Transistor Lab - PHYS 2300 Transistor Lab Transistor...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
PHYS 2300 – Transistor Lab Transistor Junctions are Diodes Here is a method for spot-checking a suspected bad transistor: the transistor must look like a pair of diodes when you test each junction separately. CAUTION: do not take this as a description of the transistor’s mechanism when operating! It does not behave like two back-to-back diodes, like the right hand side of the figure below. Get a 2N3904 NPN transistor, identify its leads, and verify that it looks like the object shown to the left in the figure above. Use the DVM’s diode test function (usually represented by a diode symbol) to measure the voltage across the BC and BE junctions. The diode test applies a small current and the meter reads the junction voltage. You can even distinguish the BC and BE junctions this way. The BC junction is the larger of the two; the lower current density is revealed by a slightly lower voltage drop. Emitter Follower Wire up an NPN transistor as an emitter follower, as shown below.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 Drive the follower with a sine wave that is symmetrical about zero volts (this is referred to as “no DC offset”). Use the oscilloscope to observe the output. Can
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}