1. VL817 C0 and B0 VL817S pin to pin
1. What is the ripple requirement of each power supply?
No special requirements. DC-DC can basically meet the ripple requirements
2. VL817 C0/B0 VL817S are independent FW
3. VL817 C0 is an advanced version of B0
2. What is the timing requirement between 3.3V and 1.2V?
Attached is the power-on sequence of VL817(S). In the reference line, there is no increase in the upper part 0. 1uF to adjust the timing.
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4. VL817S is powered by external LDO
The use of external power supply does not need to be connected to 5V, please refer to the reference design for grounding of HUB 5V. Internal 3.3 LDO output please leave
open. 1. 2V LX and FB please leave open. Shown below, see Reference Design for details.
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3. The comparative test data of the two chips, 817 and 817S, needs to be provided. We need to
evaluate the key test content and precautions based on your data.
The internal test is OK, and the report is still being sorted out. , and send it to you after sorting it out.
4. It is necessary to provide LAYOUT guidance documents or reference PCB files,
please refer to the attached PCB Design Guide Lines is the latest Layout Guide
VL817 Power On Sequence power-on sequence: