Some difficulties in geting my LTC4015-Board running the first time. Technical data:
- V-in = 12V ... 20V
- V-sys = 8V ... 20V
- V-bat = 8V ... 12,8V, 8 x NiMH in series
- I chose 3xLiIon programmable
- I-charge = 3A (max)
- I-discharge = 3A (max)
- I-sys: 4A max
- No software installed yet.
The whole system went perfectly on demo circuit DC2039A.
The two difficulties are:
- 1. Infet-Pin (34) was never above V-in, so the Fet of the ideal diode was never conducting. Only the body diode of the in-Fet. It got warm to 90°C.
- 2. Buck Converter was never running, excepted one situation: Instead of a battery I took 6 x SuperCaps in series (100F, 2,7V each + 8 x 3,2 kOhm to symmetrize) to make the charge- and discharge time smaller. When the SuperCap voltage was between 5,0V and 5,2V the buck converter startet , when V-in startet, but stopped 1 sec later. The SuperCap was charged with some mV.
Now my questions:
- Why do Infet-Pin and Buck-Converter not start ? Are there any pre-conditions I did not take care off ?
I checked the boost capacitor (datasheet p.44, 470nF like the democircuit) between boost and SW-pin. My Buck-Mosfets are PSMN9R1-30YL,115 with input capacitance = 894pF. It should work in my eyes ...
Thanks for support
This is for a custom design, right? I've sent you a friend request. Can you share your schematic and PCB layout with me privately?
Hello Zack, thanks for your kind offer, but how do I accept your friend request ? I cant find any button to accept in ez. To answer your email to "email@example.com" does not sound like a successful step. So what to do ? btw: Thanks for your quick answer :-)
found it on your email
Customer support continued through email. Considered close.