To decrease the dissipation in the LM25149 internal VCC regulator in our application, we need to supply 5V external bias to the LM25149 VCCX-pin. We are using precision enable with a resistive divider on the enable pin.
Section 8.3.3 of the datasheet states:
"When using precision enable and a VCCX supply, place a series diode with the cathode connected to the LM25149 VCCX pin."
Can you please elaborate on the exact use of this mentioned diode - is the anode connected to the external 5V supply so the bias is supplied through the diode?
We have tested with the external 5V VCCX-supply connected directly to the LM25149 VCCX-pin and that seems to work fine - and the mentioned diode does not seem to exist in any of the typical applications in section 9.2 of the datasheet (there is seems to be connected directly).
Thank you very much!
