In this video we are going to talk about the protection capabilities of the ZL8800. This is a dual output or a dual phase device. So I'm just gonna show one channel because whatever happens for this, is applicable for both of them.
The device is very comprehensive and has a range of protection options. So as you will walk through the schematic we can talk about each and every settings that can be individually adjusted through the PMBus interface, so as we look at the input, the device monitors the input current but then we also have the ability to monitor the input voltage and set alarms whether it's overvoltage or an under voltage event. And it stops the device from reacting negatively in those situations.
Another possibility is on the output voltage, this is constantly monitored and we have a very fast volt responses for overvoltage and under voltage events. For current, it's the same thing, the output current can be constantly monitored by looking at the DC or inductor current, and so we can respond to either overcurrent events or also undercurrent events, so in that case, you can set the device so if there is ever a negative current, that could occur in some applications, you can set either at levels very far below ground or below zero amps I should say or we can have it at zero amps to prevent negative current from occurring.
All these settings feedback in the device and you have got a couple of ways of monitoring the status, there is a power good pin which will always alert you whether the output voltage is in the regulation or not.
The other way you have to monitor the device is through the PMBus interface and this is essentially the SMBus interface or the I2C with the PMBus commands, this gives you the ability to read the status at all times upon all these parameters, find out whether a fault has occurred, and it is also a snapshot tool built into the device which is essential like a black box capability. If there is ever a fault, the device will set the flag and alert you and you can go in and query to find out exactly what fault occurred, so maybe during qualification, there is an overvoltage event that occurred on the output, you can go back in after days later and look to see what that last fault was, so you can go back and find the root cause.
In the subsequent videos, we will go through each one of these faults in detail and look at how to set them up.