...| |
| | __V2__|
<-t1-> <-t2->
Due to above values and asume that VDC is the displayed value on the volt meter, we have:
VDC=((V1*t1)+(V2*t2)/(t1+t2))
if V2=0 then VDC=V1 * t1/(t1+t2) where t1/(t1+t2)=Duty Cycle
Hence:
Duty Cycle= VDC/V1
and Duty Cycle% = (VDC/V1) *100...
take a look at: Art of electronics by paul horowitz
it's a really nice book and also contains some helpful informations about grounding considerations and low noise devices.
you can also use S-R latchs which are very inexpensive and 6 of them are integrated in a single chip and also most of the semiconductor making factories have these chips.
S-R latchs are great for debouncing a push button!
Hi
National Semiconductor has a very powerfull Microcontroller with A/D, D/A, PWM, CTCs, SPI, UART and ... peripherals (Sorry i forgot it's number!).
you can also use ATmega Microcontrollers of Atmel corporation.
and at last take a look at Microchip, they have very nice and high efficient MCUs.
Most TV remote controllers send a conventional number of pulses to IR emitter diode in a known amount of time, to send a command to TV.
For exmaple to send ON command, you can send 10 pulses in 2 milliseconds!
Ofcourse these numbers vary on different types of remote controllers.
But, I didn't...
try Analog devices AD202, it can do, what exactly you want.
but the only problem is it's cost, it's a lil bit expensive.
the another way s using linear opto couplers such as CP Clare's LIA100, they send 2 or 3 samples of their ICs if you want.
I think HP no longer produces any semiconductor...
Hello liu93083,
Photodiode generates a small current proportional to amount of light which is directed at it's face!
This current is very small, usually in range of micro amperes, so if we want to show amount of light in a screen whether digitally or even analog then we have to first change...
...low ripple, full input protection in two versions
(LM2907-8, LM2917-8) and its output swings to ground for a
zero frequency input.
Advantages:
* Output swings to ground for zero frequency input
* Easy to use; VOUT = fIN * VCC * R1 * C1
* Only one RC network provides frequency doubling
*...
there is an IC that provides everything you want!
national semiconductor's LM3915:
The LM3915 is a monolithic integrated circuit that senses analog voltage levels and drives ten LEDs, LCDs or vacuum fluorescent displays, providing a logarithmic 3 dB/step analog display. One pin changes the...
hi
use ULN2003 to drive relay from a digital circuit like a microcontroller or even you can use a single transistor.
you can see ULN2003's data sheet on www.ti.com
555 can handle your purpose.
in astable configuration the pulse period is equal to
T=.693*C*(2Ra+Rb)
where Ra is resistor between pin number 6 and 7
and Rb is resistor between pin number 7 and 8 or Vcc (+5)
high time=.693*C*(Ra+Rb)
low time =.693*C*Ra
you can make very large duty cycle with...
Hi
why you think 80 C is a high temperature for a power supply circuit
when a approximately 20 watt none switching power supply works it's temperature rises about 150 c !
you want a 24 V DC 50 watt power supply
and if you don't want to waste your money you must make it by urself
now i'll guide...
you must use a schmitt trigger to have a stable comparator
by using positive fidback.
if you dunno what is a schmitt trigger you can contact me
by this email address:
kasra_ravanbakhsh@hotmail.com
or see any electronic books!!!!
such as Integrated Electronics by Millman-Halkias
McGraw-Hill...
...anti logarithmic amplifier to make a multiplier.
with just four OP-AMPs and two diods or two transistors and it's very low cost.
with this theory:
x*y=exp(ln(x)+ln(y))
because ln(x)+ln(y)=ln(x*y) and then exp(ln(x*y))=x*y
;)
and making logarithmic and antilogarithmic amplifiers and an adder...
