Hi,
On the LMZM33604EVM, is it normal for the VFB to change when IOUT starts dropping below 1.0A?
Setting the output to 5V, I observed that my output voltage is stable at 5.068V (RFBT=56k, RFBB=13k92) when IOUT is high and down to about 0.7A. Then the following happens..
| IOUT (A) | VOUT (V) | VFB (V) |
| >1.0 | 5.068 | 1.004 |
| 0.7 | 5.070 | 1.004 |
| 0.6 | 5.081 | 1.006 |
| 0.5 | 5.086 | 1.007 |
| 0.4 | 5.099 | 1.010 |
| 0.3 | 5.109 | 1.012 |
| 0.2 | 5.121 | 1.014 |
| 0.1 | 5.131 | 1.016 |
| 0 | 5.138 | 1.018 |
So it seems the increase in VFB is causing the output voltage to increase since the feedback resistor ratio has not changed. When the load is disconnected, VFB becvomes 1.018 which is higher than maximum stated in the datasheet (May 2019).
Is this normal or do I have a faulty chip?
Thank you,
Best regards,
Saxon
