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70 Threads found on edaboard.com: Zener And Regulator
The aim is to prevent battery voltage from going over 13.8 volts or so. This simple zener and NPN regulator might be PV panel voltage varies according to how much current you draw from it. No-load maxi
I have used a NPN power transistor (BD137) plus a 270Ω resistor and a 5V zener to make a regulator which gives me a 4.4V output which is still too high. BD137 isn't suited for 2A load, neither in terms of rated current nor power disspation.
Simple transistor and zener regulator. (The zener can also be a combination of diodes/ led's/ current goes through the load, so it may not be satisfactory with every load.
Hi all, I've made a Remote Controlled switch using TSOP1738, a Timer 555 and a CD4017. The working is this : 1) The 555 timer is set to monostable mode with the trigger input connected to the output of TSOP1738 2) Whenever pulsed IR falls on the TSOP1738, it triggers the timer. 3) The timer drives the clock of CD4017. 4) The CD4017 is wired
Your schematic shows no filter, it is simply a voltage limiter consisting of R 65 and CR 11 (a zener diode). The capacitor is not necessary. If it might filter anything then one will need to know the Vin source impedance.
Thanks all, Do you have any idea why they used 220/15V transformer and then used zener to regulate voltage to 3.3V ?! why didn't they use lower voltage transformer instead of 15V ? the higher voltage just makes much loss power on zener or the regulator ! and about life time ? which type usually has longer (...)
This is basically a continuous Buck regulator switching oscillator than regulates the pulse width for an average DC voltage across Vbe controlled by D1 zener voltage , Vbe and Ie*Re and duty cycle. Offline buck designs have improved over this and work in principle like active PFC to provide a sinusoidal (...)
A low voltage zener diode is a poor voltage regulator because its voltage changes with load current and with temperature changes. A zener diode wastes battery current all the time. Instead you should use a low dropout linear voltage regulator IC. The one I use is not made anymore but I still have some to use (...)
There are good reasons to stay with transformers and linear voltage regulators for your project. Using integrated voltage regulator ICs instead of discrete voltage regulator circuits with transistors, zener diodes etc. utilized in the original Moog devices can make the design a bit more convenient but (...)
Dear All, I heard that in vehicle use it's good idea to protect regulator from voltage spikes. So my question is, does this circuit work? 111312 Idea is that the zener diode will ground through that 60ohm resistor voltage over 18V which is way before the maximum limit of 25V of LM7805 regulator voltage limit.
zeners are not efficient nor stable compared to bandgap reference diodes used in all LDO's (LM317 type and many others) zeners must draw more than the worst case load to ensure when loaded there is still enough current to get past the knee in the zener. Then when no load, that current * voltage can lead (...)
Use the switching regulator or dc-dc charge pump convertor like MCP1252 etc. You can also use linear drop out regulator like LM series. zener diode will work too but heat dissipation will rise. But, if you are worried about the transient and spike protection, simply use metal oxide varistor or diode bypass circuit to power (...)
u have to add a current limiting resistor between diode and ground if u want to limit the current to zener and prevent overheating. Put the value of resistor which will not cross your zener max reverse current specification. If this zener diode is used for power supply, i suggest using switching (...)
Ambient temperature changes the base-emitter voltage of the transistor a little and changes the voltage of the zener diode a little. They work well between -55 degrees C or less to 150 degrees C or more. Of course if they have power dissipation then they heat themselves higher than the ambient temperature. Look at their datasheets to see.
There is no filter capacitor after the rectifier? 350W for the output is almost THIRTY amps! If you have a regulator why do you need a series zener based regulator?
not sure how you define 'best' mriad of ways: from LM317 to plain old series pass regulator with a zener diode. Or a voltage divider. Cheapest solution. and possibly worst solution.
Just cut the grounded terminal of R2 and connect it to the cathode of a 16 V zener diode and connect the anode to the ground.
you can vary the o/p by changing r2. zener also can be adopted as a reference & it will give you a very precise o/p
it will be a affordable to by a 9volt 500ma transformer rather than using any dc to dc converter use lm317 as a voltage regulator to get 3.3v or simply use a zener
Hi Steven, I clearly am not in the league with your other helpers, but here goes: 1 solution: use a zener diode and a resistor as a simple regulator, yes simple, yes there will be heat dissipated. To spread the heat(and current) set one up for each string. 2 solution: Use a transformer in your power supply. You (...)