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Part Number: DLPA2000
The maximum LED current we are aiming for is only ~300mA. However, transitioning between Red, Green, and Blue, there are huge input current spikes (1.5A) since the buck-boost is trying to fill the output capacitors as fast as possible. I am worried these current spikes will result in voltage dips throughout the entire VSYS rail that will cause buzzing caps.
Since the target current is much lower than the chip's max current (750mA), is there any way to reduce the input current spikes?
Could we reduce the VLED capacitance since our max loading current is lower than normal?
Are there any internal registers that would slow down the VLED voltage ramps?
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In reply to Kyle Rakos:
Below is a screenshot of the input current waveform for the entire PMIC. This is sensed across a 10mOhms resistor with a differential probe. Is this magnitude current spike expected?
In reply to Gerald:
Below is a section of our schematic specific to the VLED buck boost.
Note that 2 of the PPVLED capacitors are not placed. The total output capacitance is ~44uF for the waveform i presented. I will provide a combined V and I waveform shortly.
CH3: VLED CH4 ILED (anode):
CH3: VLED CH4: I_Input
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