As I move foreword and away from simple projects Could someone help me figure out how much current I am sourcing from my stamp. Anyways I have attached the datasheet for the part to this post. I am using what I believe to be quality transistors, ST 2N2222A, I say this in reference to erco mentioning the lower quality ones the shack sells. 2N2222A HIGH SPEED SWITCHES PRELIMINARY DATA DESCRIPTION The 2N2219A and 2N2222A are silicon Planar Epitaxial NPN transistors in Jedec TO-39 (for 2N2219A) and in Jedec TO-18 (for 2N2222A) metal case. I have one followup question to this excersize. I fired up the stamp, made pin 15 high and it worked!.and changing the the negative terminal on the motor.Below is an updated schematic, the changes are the addition of the diode, resistor value change, a lower voltage motor, 2N2222A NPN Transistor, 60V 500mA, TO-18 (4 pack) The 2N2222A NPN Transistor are designed for high speed switching application at collector current up to 500mA. I got a lower voltage motor, 3V, and put in a 500ohm resistor, I forgot to get some 470's at the shack and the 500's were all I had. Mike, following your advice, I put a 1N4001 diode in place. Erco, using that relay will be my next learning excersize. I got a multi pack of rectifier diodes, a lower voltage motor, and picked up one of the reed relays erco mentioned. For 2.5W into 4 ohm speakers at fairly low distortion I would use a PAM8403 stereo class-D audio amplifier IC powered from 5V and it costs.
#2n2222a transistor in grayson ga full
Try increasing base current to maybe 10mA.Well I swung by the shack today and picked up some parts. A 'simple' amplifier made with a low current 2N2222 transistor will produce a low output level full of distortion. This is okay, and the transistor will be fine!īUT, back to the saturation range, if you increase your collector-emitter current you will move further right on the graph, look at how far right the 500mA graph is, at 500mA your 2mA base current would create a huge voltage drop across collector-emitter! This means that at motor startup, or if you increase motor current too much you will have a dramatic heating in the transistor, probably welding collector-emitter to a short-circuit! If you look at the graph for 150mA you will see that with 2mA base current you will have a Vce (collector-emitter) of about 0.15 V, which is probably okay since you will have very low power dropped, 0.15V * 0.15A = 0.0225 W.Īlso in the data sheet you can see that the transistor will heat up 200 ☌ per Watt dissipated.Ġ.0225 * 200 = 4.5 ☌. Now look at the table from the data sheet about the Collector Saturation Region. You have put a 2k2 resistor with 5V on your base, you will drop about 0.7V from base to emitter, that means that there will run about (5 V - 0.6 V) / 2200 = 2mA through your base. can someone please explain to me what im experiencing here? thanks my base resistor which i blindly picked from the 2k200 OHM pile is connected to a 5VDC Source along with a 10kOHM pull_down resistor on the base of the transistor. this is especially true if i cold start the motor at 20 or higher volts. On the motor i have a flywheel diode and a filtering cap however if i raise the voltage about 19.0 volts something happens to the transistor and it seems as if it shorts to the on position because when i pull the base low the motors is still running and the transistor begins to heat fast. letting the motors run at 12V for numerous hours consuming. So just for fun i hooked up a 12VDC motor that according to my "RIGOL DP832A Programmable Power supply" is consuming about. Focusing on transistors, more specifically the "ON Semiconductor P2N2222A NPN" According to the specs here the transistor has a maximum emitter voltage of 40VDC and a collector current rated at 600mA. Right now i'm tinkering with MOSFETS and NPN Trainsistors.
0 kommentar(er)
