Other Parts Discussed in Thread: LM5176
I have created a variant of the evm board from files previously provided in this forum, effectively so I can use it for a custom battery charging solution. First off, I own one of the EVM boards and can confirm it works very well. I have been trying to do both schematic and electrical comparisons between the EVM board when its in operation against the one I have designed.
Powering mine up I noticed that its default power usage is ~85mA@12V against the 15mA@12V on the evm board. My board is outputting at 0V at Vout. A few obervational notes:
- The input series 10Ω resistor to Vin is dropping ~800mV
- HDRV1 is showing as a noisy ground signal. Even after disconnecting all components on its net, its still sits at 0. See scope below.
- I have 2 boards built up that have the same current draw/results/issues
- When i pull the enable pin to ground, my board draws 0mA, so it appears that current is not leaking outside of the IC
- I have reflowed majority of the components at least once and tested everywhere possible for shorts
I created the following table of observations:
|Pin Num||Devboard||Custom board||I/O||Function|
|3||11.6 Noisy||11.8||I||Vin Sense|
|23||7.4||7.3||I/O/P||Vcc - Out|
HDRV1 output signal: scoped
Schematic PDF for better resolution: http://a.uguu.se/7pnQPFOL2gKW_LM5176Customboard.pdf