LM5176: LM5176 output current not enough

Hello CS kk,

Is it possible that the device gets very hot in these 5 minutes?

Would you please measure the input and output voltage with a scope while the output voltage falls down.

Hello CS kk,

Any update on the issue?

dear

1. At present, we are producing 450W 24V output power. May I ask what is the maximum power of this chip?

2. At present, we use two sets of LM5176 for 225W and 450W 24V in parallel. As a result, two SETS of LM5176 are burned as soon as the power is switched on. The parallel mode is Vin+ and VIN-parallel, and the two sets of Vout+ and Vout-parallel

3. When the power supply has overload protection and short circuit protection, is there any way to realize that when the overload protection or short circuit protection is removed, the output voltage can be restored only after the disconnected power is restarted. At present, the output voltage can be restored automatically after the chip is removed

any advise?   thanks in advance

Hello CS kk,

1. I would say that with an output power of 450W you are coming close to the internal driver capability with the external MOSFET gate charges, but this depends on the used MOSFETs.

2. If you are putting 2 different converters with separate voltage loops in parallel, one of them will most probable take all the power and the other one will not do anything. The reason is that they do not have exactly the same output voltage and the one that has a slightly lower reference voltage or slightly different result in the resistor divider will always think that the output is high enough, so it does not need to do anything. You need to define a main and secondary device and connect them according this app note: 

3. If I understand your comment correctly, then the MODE pin setting into hiccup mode (R = 93.1 kohm) would solve this issue. In hiccup mode, the converter tries to restart after some time when it got into overcurrent.