Transistor Microphone Amplifier: 4 Kauj Ruam

2024 Tus sau: John Day | [email protected]. Kawg hloov kho: 2024-01-30 09:25

Kab lus no qhia koj yuav ua li cas ua lub transistor microphone amplifier.

Qhov tsawg kawg nkaus lub zog hluav taws xob rau cov kab ke no yog 1.5 V. Txawm li cas los xij, koj yuav xav tau yam tsawg 3 V yog tias koj tab tom xaiv qhov ntsuas pom pom LED (transistor Q3) thiab xav kom koj lub LED qhib.

Lub teeb liab los ntawm lub microphone tau nthuav dav los ntawm transistor Q1 thiab Q2 ua ntej thov rau Q3 transistor rau kev kuaj pom.

Koj tuaj yeem pom kuv txoj haujlwm ua haujlwm hauv daim vis dis aus.

Kuv xav txog lub tswv yim no tom qab nyeem kab ntawv no:

Khoom siv

Cheebtsam: lub microphone pheej yig - 2, lub hom phiaj dav dav transistors - 5, 100 ohm lub zog loj tiv thaiv - 5, 1 kohm resistor - 1, 10 kohm resistor - 10, 470 uF capacitor - 10, 220 kohm resistor - 2, 470 nF capacitor - 5, pawg thawj coj saib xyuas, thaiv cov xov hlau, 1 hli hlau xaim, 1.5 V lossis 3 V lub zog siv (AAA/AA/C/D roj teeb), 1 Megohm txog 10 Megohm resistor pob.

Cov cuab yeej: pliers, hlau stripper

Cov khoom siv xaiv tau: cov laug, LEDs - 2, hlua roj teeb.

Yeem cov cuab yeej: cov hlau txuas, USB oscilloscope, multimeter.

Kauj ruam 1: Tsim Circuit Court

Xam qhov siab tshaj plaws LED tam sim no:

IledMax = (Vs - Vled - VceSat) / Rled

= (3 V - 2 V - 0.2 V) / 100

= 0.8 V / 100 ohms

= 8mA

Xam lub Q1 transistor sau qhov hluav taws xob, Vc1:

Vc1 = Vs - Ic1 * Rc1 = Vs - Ib1 * Beta * Rc1

= Vs - (Vs - Vbe) / Rb1 * Beta * Rc1

= 3 V - (3 V - 0.7 V) / (2.2 * 10 ^ 6 ohms) * 100 * 10, 000 ohms

= 1.95454545455 V

Cheebtsam tsis sib xws yog tib yam rau lub transistor thib ob amplifier:

Vc2 = Vc1 = 1.95454545455 V

Lub transistor yuav tsum muaj kev ntxub ntxaug ntawm ib nrab ntawm qhov hluav taws xob 1.5 V, tsis yog 1.95454545455 V. Txawm li cas los xij, nws nyuaj rau kwv yees qhov nce tam sim no, Beta = Ic / Ib. Yog li koj yuav tsum tau sim sib txawv Rb1 thiab Rb2 resistors thaum tsim hluav taws xob.

Xam qhov tsawg kawg Q3 transistor tam sim no nce kom ntseeg tau saturation:

Beta3Min = Ic3Max / Ib3Max

= Ic3Max / ((Vs - Vbe3) / (Rc2 + Ri3a))

= 10 mA / ((3 V - 0.7 V) / (10, 000 ohms + 1,000,000 ohms))

= 10 mA / (2.3 V / 11, 000 ohms)

= 47.8260869565

Xam qhov qis dua qhov siab lim zaus:

fl = 1 / (2*pi*(Rc+Ri)*Ci)

Ri = 10,000,000 ohms

= 1 / (2*pi*(10, 000 ohms + 10, 000 ohms)*(470*10^-9))

= 16.9313769247 Hz

Ri = 1,000,000 ohms (rau LED ntes)

= 1 / (2*pi*(10,000,000 ohms + 1,000,000 ohms)*(470*10^-9))

= 30.7843216812 Hz

Kauj Ruam 2: Simulation

PSpice software simulation qhia tias qhov siab tshaj plaws LED tam sim no tsuas yog 4.5 mA. Qhov no vim tias Q3 transistor tsis txaus vim qhov tsis sib xws ntawm Q3 transistor qauv thiab lub neej tiag tiag Q3 transistor uas kuv tau siv. Q3 PSpice software transistor qauv tau qis heev tam sim no nce thaum piv rau lub neej tiag tiag Q3 transistor.

Bandwidth yog kwv yees li 10 kHz. Qhov no tuaj yeem yog vim lub peev xwm transistor stray. Txawm li cas los xij, tsis muaj kev lees paub tias txo Rc tus nqi tiv thaiv tus nqi yuav nce bandwidth vim tias transistor qhov nce tam sim no tuaj yeem txo qis nrog zaus.

Kauj Ruam 3: Ua Circuit Court

Kuv tau siv qhov kev xaiv fais fab lim rau kuv lub Circuit Court. Kuv hla qhov lim no los ntawm kev kos duab hauv Circuit vim tias muaj peev xwm ua tau qhov hluav taws xob poob qis uas yuav txo qis LED tam sim no thiab teeb pom kev ntawm LED.

Kauj ruam 4: Xeem

Koj tuaj yeem pom kuv lub USB oscilloscope qhia qhov yoj yoj thaum kuv tham hauv lub microphone.