I'm a little bit confused about TV damper diode current specs. Specifically the maximum current and the peak current.
I'm using EY88 diodes in my power supply in a full wave center tapped configuration. My amp consumes 250 mA.
EY88 max current is 220 mA. Peak current is 550 mA.
My amp has been working flawless for months so I'm not that worried, but still, they are above their max apparently.
I understand that what they were intended for is not the way I use them,. but I'm having trouble giving it a place. Why the difference between maximum and peak current? Is 220 mA what it can take continuously (non stop) and 'peak' for occasional short bursts? Which one is closer to rectifying 50 Hz AC?
Any insights would be appreciated, thanks.
I'm using EY88 diodes in my power supply in a full wave center tapped configuration. My amp consumes 250 mA.
EY88 max current is 220 mA. Peak current is 550 mA.
My amp has been working flawless for months so I'm not that worried, but still, they are above their max apparently.
I understand that what they were intended for is not the way I use them,. but I'm having trouble giving it a place. Why the difference between maximum and peak current? Is 220 mA what it can take continuously (non stop) and 'peak' for occasional short bursts? Which one is closer to rectifying 50 Hz AC?
Any insights would be appreciated, thanks.
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The EY88 average current limit is for a single diode. Since you have a full wave rectifier, the individual diode load is actually about 125mA. The peak repetitive plate current is 550mA but, so long as your filter is not too extreme (i.e. first cap not too large or choke input topology), the peak plate current could easily be less than 550mA (or at least similar).
Personally I'd expect a good long lifetime from these little diodes.
Personally I'd expect a good long lifetime from these little diodes.
Thanks. I edited my post, mostly because I forgot to mention that it's a center tapped transformer. So if I understood correctly each diode takes turns supplying the full 250 mA.
The rest of the PS is 60 µF - 10H - 90 µF.
Not really. Each diode conducts during one half of the cycle. But the 250mA rating is the average plate current. So by definition the average is 250mA/2 for each diode. But the peak current rating of the diode is 550mA . This means that each diode must not be passing more than this peak current in order to average that 125mA. The peak to average ratio in a capacitor input power supply topology is usually between 4:1 and 6:1. It depends on the specific conduction angle.
If the amp has been working fine for months, I really wouldn't worry about it.