# Tag Info

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The Cross point is very important. Below the crosspoint you have thermal stability of paralleled devices. Above the crosspoint you may not depending on your heat sink system. Low crosspoint is better. Many devices have a crosspoint that exceeds their rating which is a disaster.

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It doesn't have any special meaning, but at that point (about VCE=1.25 V in the example), the current that flows is independent of temperature. The temperature independent occurs because the VCE is a combination of a PNP junction voltage and the VDS voltage of the internal structures in the IGBT. The PNP junction voltage has a negative temperature ...

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I disassembled this transformer and determined its following data: primary winding - 27 turns, wire diameter 0.11, two secondary windings, each with 30 turns, wire diameter 0.1. The outer diameter of the ferrite ring is 9 mm, the inner diameter is 6 mm, and the height of the ring is 5 mm.

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If your load resistance is below 0.75 ohm (with safety margin and at room temperatures,) a pulsed inrush current from capacitor C2 could surpass the datasheet specification for maximum pulsed current of 84A. That IGBT adds 0.17 ohm for a voltage drop of 1.7V for 10A measured to load resistance and on about 4V for 84A that calculates to only 0.012 Ohm. ...

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"Threshold" in MOSFETs and IGBTs is a trap for newbies. It's a deep technical term that has to do with the shape of the current vs. gate voltage curve, but isn't something that you can just measure. Probably the simplest way to put it is it's the gate voltage where the device just barely starts to conduct -- but even that is kinda-sorta wrong. For ...

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The IGBT may have a Vth of 3-6V, but it'll need 10-15V to properly turn on to its minimum on-state resistance. The gate threshold voltage is determined under this condition: Take a look at the Vge vs Ic graph in the datasheet From the graph, at Tj = 25, you can see that the IGBT needs close to 6V for an amp of current to start flowing through it. ...

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According to this post it has a relative high gate resistance in order of 100 Ohm to 1 kOhm. Perhaps you do need this way: simulate this circuit – Schematic created using CircuitLab EDIT: The datasheet values are obtained with RG=1k, so there might be a reason for that. If you look the internal structure of the this IGBT hybrid, you can see that it ...

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Also I'm not sure if gate driver has any additional benefits for current application. Given the speeds you are operating at you shouldn't need a gate driver but, watch out for $C_{IES}$: - You should consider $C_{IES}$ because it is approximately 2 nF and, the gate resistor (if you use one) will have a slight effect. However, if the gate resistor is 1 ...

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