Hi,
I'm using TPS61163 on a new design using a 8LEDs per String, 2 String LCD.
I see switching at the immediate start or after toggling the enable pin high, but after a few cycles the part seems to be disabled & our 5V input power, is passed through to our LCD anode instead of a boosted voltage.
I'm hoping someone can point me in the right direction of where to look, as the micro bga pins make it hard to debug.
The part does not seem to be going into a protection mode, as I would expect the part to start switching again after the appropriate amount of cycles have passed, but this is not the case.
Is there any way to find out the status of the LED string in the display?
I expect that 0V on one of the feedback pins means the LED string is open, while a voltage about equal to the SW pin, would mean that LED string is shorted...
So, is there a voltage I can expect to see there, or do I need to measure the current to truly get idea of the LED string's status?
Can Vin, En, and PWM all be brought up High at the same time, such that connecting them all to our 5V input power, would put the part into normal operation when the 5V supply is turned on?
On the PWM timing diagram it shows Enable and PWM pins start low and are brought up high after a bit of time, is this necessary?
I appreciate any help,
Daniel Abbate