The FMMT718 Range, Features and Applications:  Zetec Semiconductors  Applications Notes Following on from AN11, this note introduces other members of the Zetex SuperSOT series, and concentrates on the PNP options and complementary NPN/PNP designs.  Replaces SOT89, SOT223 and D-Pak Products with High Current SOT23 Bipolar Transistors  (app note added 2/06)

The ZTX415 Avalanche Mode Transistor: An Introduction to Characterisation, Performance and Applications:  Zetec Semiconductors  Applications Notes Avalanche mode switching operation of bipolar transistors is a useful but sometimes frustrating experience due to the lack of suitably designed components, and an understanding of their limiting values. The ZTX415 is the industry's first device that has been designed specifically for this function, and this note provides parametric background, typical application circuits, and also lists useful references.   (app note added 2/06)

Three Transistor Audio Amp (50 Milliwatt ):  Here is a little audio amplifier similar to what you might find in a small transistor radio. (added 8/03)

Three Transistor Audio Amp 50 Milliwatt:  Here is a little audio amplifier similar to what you might find in a small transistor radio. (added 6/06)

Three Transistor FM Radio Bug:  (circuit / schematic design added 6/06)

TN06 Series:  Supertex Semiconductors  (app note added 2/06)

Touch Switch using Transistors:  (circuit / schematic design added 6/06)

Transistor and FVCs Make Linear Anemometer:  09/26/96 EDN-Design Ideas / (added 11/05) The basic operation of this front-end sensor is identical to that of the earlier circuit. Q1 is the self-heated airflow sensor; Q2 senses ambient temperature. Zero-adjust resistor R2 sets the zero-airflow quiescent bias currents for Q1 and Q2. With proper adjustment of R2, the temperature rise of Q1 from its collector power dissipation reduces its VBE (at a rate of 2 mV/8C) to just slightly below the sum of Q2's VBE plus the drop across R1. Comparator IC1A then has a noninverting input whose voltage is slightly less positive than the inverting input. Its output, therefore, goes low, holding C1 discharged and multivibrator IC1B reset, with its output high. This condition produces a 0V output in switch S3 and, consequently, the output of IC2....  

Transistor Audio PreAmplifier:  (schematic added 8/03)

Transistor Buffer:  (circuit added 10/06)

Transistor Diode IC outlines:  (electronic circuit added 10/05)

Transistor Forms RS-232C Digital Thermometer:  05/09/96 EDN-Design Ideas / (added 6/03) An ordinary transistor can serve as an uncalibrated temperature sensor (Figure 1) for an accurate, PC-compatible thermometer. Unadjusted accuracy is more than 0.5°:C over the -50 to +50°C range, and the only limitation on resolution is the time devoted to measurement acquisition. For example, 0.1°:C resolution requires less than 1 sec. The thermometer derives all its power from the RS-232C COM port. Therefore, a laptop computer running a simple data-logging program yields an inexpensive, portable temperature-logging system....

Transistor linearly digitizes airfLow:  09/19/02 EDN Design Ideas  /  (added 1/05)  A sensitive and reliable way to measure airflow is to take advantage of the predictable relationship between heat dissipation and air speed. The principle of thermal anemometry relies on King's Law, which dictates that the power required to maintain a fixed differential between the surface of a heated sensor ....

Transistor organ:  This simple circuit can provide hours of enjoyment as you learn tunes, play duets or just make some really weird sounds by pushing all the buttons at once. You have probably seen this circuit before, it is fairly common. I have seen it in several books. The best thing about the circuit is that you can tune each individual note, or go to a whole new octave by changing one capacitor (C1). Because of this, it is possible to from an entire Transistor Organ ensemble. Why you would want to do this is anyone's guess... (added 4/05)