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I recently decided on the Delta D12F200 DC/DC converter for my current project (datasheet: https://www.mouser.com/datasheet/2/632/DS_D12F200-1141659.pdf). My project will be powered by lithium ion batteries, so having a built-in programmable under-voltage lockout will be a big benefit. However, I am having a bit of trouble understanding the formula for programming the under-voltage lockout. The datasheet describes it with the following formula:

Input under-voltage lockout formula

What I am failing to understand is where I get "Ven", as this is not described anywhere else in the data sheet. My best guess is that I should read that part of the formula as 14 * "minimum allowable voltage" + 3.8. I am hoping someone with experience on the D12F200 or similar DC/DC converters can help me out here.

I am also a bit confused on how pulling the enable pin low with a certain resistor value changes the lockout. The enable pin will be driven above 1.6 volts to turn the converter on and according to the data sheet, turns off when pulled below 600mv. I also thought of using a zener diode (and possibly a voltage divider as necessary) to control the enable pin state, but I don't want to mess up the programmable lockout due to lack of understanding. I am pretty space limited for this circuit, so I can't use anything more than a handful of components to prevent the battery voltage from dropping below ~8.5-9v under load (3s battery lithium ion pack).

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I would interpret the equation to mean Ven as the underlocking voltage, then find Ren.

So if I wanted the underlocking voltage to start at 5V,

\$ R_{en} = \frac{315}{14*(5)+3.8} = 4.26\$

At this point I would assume they mean 4.26 kiloohms, but this is not clear, you could experiment with the device and turn down a lab supply below the 5V limit and see if the device shuts off, and that would confirm the intuition.

But really, this datasheet is crap. There is no other information at all in the datasheet and no nice example table like there is for Rtrim. I would complain loudly to the manufacturer. They would be the best resource to clear this up, and they need to fix their datasheet.

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