Friday, October 16, 2009

Rangkaian Pre-Amp Mic 2 Transistor.

Here is a Pre-amp microphone dynamic using two transistors. The circuit factor of this around 150 and can handle signals from 50Hz to 100Khz.This circuit is designed for use with 200 Ohm dynamic microphones. For usage with low impedance microphones, the value of R3 must be increased to around 47o Ohms and C1 must be decreased to around 2.2uF.

Pre-Amp mic 2 transistorSkema rangkaian Pre-Amp mic 2 transistor

The audio signal from the microphone is coupled to the base of Q1 via the capacitor C1 and resistor R3. Q1 works as a preamplifier here. The preamplified signal will be coupled to the base of Q2 for further amplification. Resistor network comprising of R4, R5 and R6 provides the necessary negative feedback. Final output signal will be available at the emitter of Q2.


Layout Transistor BC549 & BC546

Transistor BC549 Absolute maximum rating
  • VCBO collector-base voltage open emitter...............30 V.
  • VCEO collector-emitter voltage open base...............30 V.
  • VEBO emitter-base voltage open collector................5 V.
  • IC collector current (DC)........................................100 mA.
  • ICM peak collector current......................................200 mA.
  • IBM peak base current............................................200 mA.
  • Ptot total power dissipation Tamb £ 25 °C..................500 mW.
  • Tstg storage temperature...................................... -65 to +150 °C.
  • Tj junction temperature..........................................150 °C.
  • Tamb ambient temperature..................................... -65 to +150 °C.
  • hFE DC current gain VCE = 5 V, IC = 2 mA .............420 to 800.

Transistor BC546 Absolute maximum rating
  • VCBO collector-base voltage open emitter..................80 V.
  • VCEO collector-emitter voltage open base..................65 V.
  • VEBO emitter-base voltage open collector..................6 V.
  • IC collector current (DC).........................................100 mA.
  • ICM peak collector current.......................................200 mA.
  • IBM peak base current.............................................200 mA.
  • Ptot total power dissipation Tamb £ 25 °C.................. 500 mW.
  • Tstg storage temperature........................................ -65 +150 °C.
  • Tj junction temperature...........................................150 °C.
  • Tamb operating ambient temperature ........................-65 +150 °C.
  • hFE DC current gain VCE = 5 V, IC = 10 mA..............150.

 
Skema Rangkaian Elektronika