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13 votes

What does T_L mean in a diode datasheet?

With respect to power dissipation characteristics, the temperature of the lead frame to which the chip is attached to the PCB or heat sink is relevant. This temperature is referred to as TL. ...
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12 votes

Is there such thing as an inline ideal diode?

I would argue that an ideal two-terminal diode does not exist. I am also assuming that having an internal power source, such as a battery, is not allowed. My thinking is as follows: An ideal diode ...
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11 votes
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What does T_L mean in a diode datasheet?

TL is the Lead Temperature. This is sometimes but not always defined in the datasheet.
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11 votes
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Is there such thing as an inline ideal diode?

For your application - it’s not possible to have such a diode without qualifications (unrestricted use), since they require power to operate, being active devices, and it’s not possible to get power ...
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8 votes

Is there such thing as an inline ideal diode?

While continuing a research on the topic, I've stumbled upon this chip: LM74610. So, here is a simple answer: yes, it is absolutely possible to make 2-terminal "ideal" diode. Note the term ...
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4 votes
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Reverse recovery time of diodes and its effect in buck converters

Your general understanding of the diode behaviour is correct. When the FET turns on, the voltage at its drain doesn't begin to fall until the FET's current exceeds the inductor + diode reverse ...
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4 votes

Is there such thing as an inline ideal diode?

Consider a hypothetical ideal inline diode. Connect it in series with a resistor and a DC motor. The diode would rectify Johnson noise from the resistor, thus powering the motor, turning heat into ...
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4 votes
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What type of SMD diodes are these?

I'd say those are 4 RD7.5S, Zener diodes made by Renesas: https://www.renesas.com/us/en/general-parts/rd75s-diodes-constant-voltage My Google search term: "RD7.5S" You're quite lucky, that ...
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3 votes
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Why is there current flowing through the resistor R1?

I'll assume by "input voltage", you mean \$V_B\$. We don't have values for R1 or \$I_{IN}\$, so I am not sure how one is expected to produce a graph of \$I_{R1}\$ vs. \$V_B\$. I suppose we ...
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  • 8,338
3 votes

Using 2 AC-DC adapters in parallel with block diodes to safely increase current capacity

You can indeed try this, but you have to keep in mind several things: Diodes have a forward voltage drop, I'm not entirely sure about solar panel blocking diodes, but seeing as they tolerate higher ...
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  • 103
3 votes

Diode reverse recovery time and the speed (snap back) in which recovery takes place

My experience with my own recovery test jig, is that regular rectifier diodes exhibit specified behavior (\$t_{rr}\$ and softness) for \$t_{on} \gg t_{rr}\$. This is a hidden assumption that they don'...
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2 votes

Identifying SMD diode

Try tracing the circuit (follow traces and vias between components; remove components and check continuity if necessary). I would guess the circled diode is a zener, in MELF package. The left-hand ...
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  • 3,027
2 votes

Can the connection of collector and base in these circuits be considered as a diode connected transistor?

The diode connected transistor requires a direct short circuit between collector and base, to be called a "diode connected transistor". That is, a 0Ω resistance, a wire, connects them. The ...
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2 votes

Diode reverse recovery time and the speed (snap back) in which recovery takes place

I believe--but am not 100% certain--that this "snap-back time" is what we in the semiconductor industry call \$t_b\$ (with \$t_a\$ being the rest of the recovery time--\$t_{rr}=t_a+t_b\$). ...
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2 votes

Is there such thing as an inline ideal diode?

No, for the reasons explained in other answers, but there are some things, like the TI SM74611, that get damn close. The internal charge pump means that it injects a bit of switching noise, and it's ...
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1 vote
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Do I need a diode in my circuit when using a USB-powered DC power supply to power a laptop camera?

2 silicon diodes in series will have a nominal voltage drop of 1.4V. 5V source from the USB - 1.4V drop from the diodes = 3.6V. Most 3.3V devices are probably maybe fine with 3.6V. This isn't ideal as ...
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1 vote

Is there such thing as an inline ideal diode?

No, there are no ideal diodes, just as there are no other ideal elements but you can use a diode with a lower drop. Source: https://pediaa.com/difference-between-schottky-and-zener-diode/ Another ...
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1 vote

Diode reverse recovery time and the speed (snap back) in which recovery takes place

The topology of this circuit your are testing is unusual for a SRD, as it involves such low impedances, and ignores some key parasitics. Usually, when we come to build a circuit physically, the L/C ...
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1 vote

Thermal rise for a dual diode package (common cathode)

Before or after it fails? If your assumptions are correct then the junction temperature will (typically) be around the absolute maximum 175 degrees C even with non-elevated 25 degrees C ambient ...
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