3V频闪灯电路的疑问
本帖最后由 AnJoy 于 2010-3-19 10:54 编辑按电路图做了这个闪烁电路，当我把灯泡换成LED怎么就直亮不闪烁了呢。
如果想让把灯泡换成LED能闪烁，请问电路改怎么修改呢。
按电路图做了这个闪烁电路，当我把灯泡换成LED怎么就直亮不闪烁了呢。 看不见图 看不到图。 也许是灯泡和led 的导电特性不同吧 http://pic.wenwen.soso.com/p/20091130/20091130184609-463027707.jpghttp://pic.wenwen.soso.com/p/20091130/20091130184609-463027707.jpg
试试这个
神奇的传送门:http://wenwen.soso.com/z/q167642662.htm http://www.elecfans.com/article/UploadPic/2010-1/20101179243355569.jpg
Parts:
R1_________________Photo resistor (any type)
R2________________100K 1/2W Trimmer Cermet
R3,R4______________10K 1/4W Resistors
R5________________470R 1/4W Resistor
R6_________________47R 1/4W Resistor
C1________________220΅F 25V Electrolytic Capacitor
D1______________1N4148 75V 150mA Diode
D2_________________LED Any type and color (See Notes)
Q1,Q2____________BC337 45V 800mA NPN Transistors
SW1_______________SPST Switch
B1__________________3V (Two 1.5V AA or AAA cells in series, etc.)
Circuit operation:
This circuit adopts the rather unusual Bowes/White emitter coupled multivibrator circuit. The oscillation frequency is about 1Hz and is set by C1 value. The LED starts flashing when the photo resistor is scarcely illuminated. The onset of flashing can be set by trimming R2.
Notes:
Best results in flashing frequency can be obtained using for C1 a value in the 100 to 1000΅F range.
To drive a filament lamp the following changes must be made:
Use a 2.2 to 3V, 250-300mA lamp in place of the LED
R2 = 10K 1/2W Trimmer Cermet
R3, R4 = 1K 1/4W Resistors
R6 = 1R 1/4W Resistor
C1 = 470 to 1000΅F 25V Electrolytic Capacitor
In LED-mode operation the stand-by current consumption is less than 400΅A.
In Lamp-mode operation the stand-by current consumption is about 3mA. 可以用万用表测测二极管通电电压 频闪要有取样的，可在LED发光管上并联一电阻，470--3K慢慢试好，注意LED的正负极。
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