Quote
With competitive price and timely delivery, Hornby Electronic sincerely hope to be your supplier and partner.
Voltage on VDD with respect to VSS ..... -0.6V to +7.0V
Voltage on SCL, and SDA with respect to VSS..... -0.6V to 12.5V
Voltage on all other pins (A, W, and B) with respect to VSS ..... -0.3V to VDD + 0.3V
Input clamp current (VI < 0, VI > VDD, VI > VPP ON HV pins) ........... ±20 mA
Output clamp current (VO < 0 or VO > VDD) ....................................... ±20 mA
Your statement "I still need to prevent greater than 5volts across the pot" is probably far too strong of a constraint. Where's the datasheet for your digital pot? Since you haven't provided one, I'll use this one as an example (first one that I found): MCP datasheet If you look at what the actual requirements are, in the absolute maximum ratings section:That shows you that not only is a voltage of up to VDD+0.3V (i.e., 5.3V) OK, but it also describes the limits of the included clamp diodes. So you don't need to worry at all about the voltage spec; as long as you keep the shunt currents below 20mA, you'll be fine.For instance, the 100 ohm resistor I mentioned earlier will provide protection for voltages up to 7V (20mA * 100 ohm + 5V). If you use a 1k resistor, then suddenly that goes up to protection up to 25V. This is all without using any extra diodes.If you want to use silicon protection diodes (to avoid leaky Schottky diodes), then it's pointless to put them directly in parallel with the dpot pins because the dpot clamp diodes will die before the Silicon diodes even start conducting. If, instead, you place the silicon diodes before the protection resistor, then you can create an extremely robust solution indeed with quite small resistances.There's basically no configuration in which Schottky diodes make sense, because if you put them directly on the dpot pins, you can't guarantee that the diode will actually start conducting before the clamp diodes in the IC, and if you put them before the resistor, there's no point in them being Schottky because even a normal 0.7V drop diode will work perfectly well and will mess with your signal less.The point is, this is all simulatable and calculatable using the datasheet figures; there's nothing magical or different about the job of protecting inputs.
In the last blog, we looked at the durability of SiC. In this blog, we will take a look at the properties and performance of SiC Schottky diodes, including a review of what makes Schottky diodes different and how they work.
In the typical diode, a p-n junction is formed by combining p-type and n-type semiconductors. Schottky diodes are different, however: metal is used in place of the p-type semiconductor. Then, instead of a p-n junction, you have an m-s junction known as the Schottky Barrier (which is where these diodes get their name).
How a Schottky diode works depends on whether it&#;s in an unbiased, forward-biased, or reverse-biased state. When a Schottky diode is in an unbiased state, the free electrons will move from the n-type semiconductor to the metal. This forms a barrier where the positive and negative electrons meet, and any free electrons are going to need energy other than their built-in voltage to successfully overcome this barrier.
For more information, please visit Custom Schottky diode protection Factory.
In the case of a forward-biased state, electrons can cross the barrier if the voltage is greater than 0.2 V. On the other hand, with a reverse-biased state, the barrier is actually expanded and an electric current is prevented. But there is a catch: if the reverse bias voltage keeps increasing, it can break down the barrier and cause damage.
One of the most well-known benefits of a Schottky diode is the fact that it consumes less voltage than a standard diode, resulting in a low forward voltage drop and leaving more voltage to actually power the load. Because these diodes consume less power, they work extremely well for low-voltage applications. They are also known for their high switching speeds because the small amount of charge that remains stored within the diode lends itself to faster recovery time. And, last but not least, Schottky diodes generate less EMI noise during switching.
The use of SiC with an MPS (merged-PiN Schottky) design takes advantage of the natural durability of SiC to provide a more robust, reliable, and rugged alternative to traditional Si designs. SiC Schottky diodes have better conductivity (both electrical and thermal) than their Si counterparts. These combined properties make it possible to achieve a low forward voltage drop across the entire operating temperature range of the diode, not over just a small portion. The MPS design enabled by SiC makes it possible to achieve a higher forward current-carrying capacity. The SiC Schottky diodes also have a higher breakdown voltage and better surge capability than Si models.
SiC Schottky diodes have found many different applications, mainly in power electronics. They can be found in applications related to solar cells, electric and hybrid vehicle power systems, radio frequency detectors, power rectifier circuits, and industrial power. Wolfspeed has specialized in the development of SiC Schottky diodes and their 6th generation design is ready for you to implement in your own designs.
Contact us to discuss your requirements of Custom Schottky diode EMI Factory. Our experienced sales team can help you identify the options that best suit your needs.