It seems Si3404 is a new product, so many parameters are unclear. Can Silabs provide some more informations about the loop compensation design. Such as how much is the slope compensation in the chip? This information may be useful in the loop compensation calculations.

Hi,

I designed a prototype board with POE using Si3402 for 5V output but its giving 12V instead. 

I would really appreciate if anyone can look at my attached schematics and figure out what I need to change.

 

Thank you

Si3402 is designed to deliver 24V,15W. I have done the design verification by silabs using your internal sales force. I have made the modifications in the circuit as per your recommendations.

I am using PoE Injector to provide power to PoE controller. The DC jack of PoE injector is connected to Keysight DC power supply(U8001A) and an ethernet cable is used to connect btw PoE injector and RJ-45 Jack. 

As I increased the input voltage beyond 24V, the output also increases linearly. Since this is designed for 24V, even if the input (actual input will be around 42-57V )increases beyond 24V output should stay stable at 24V. I checked this in 2 of our boards, both have the same issue.

If neede i can provide BOM also.

Is this because PoE controller is damaged?? Please put some light on this.

 

We are looking to implement an isolated design using the SI3402-C in which we only need deliver a small amount of power, less than 1W @ 3.3V. Are there any reference designs optimized at this power level? Our design is heavily constrained by board space and any modifications (such as a smaller replacement for the FA2924-ALB) that we can make would be most helpful. 

Thanks,

Pieter

Are there a variante of SI3402-B-GM with temperature range -40 ~125° or for automotive applications? We are designing a new product for automotive and must guarantee that all components can work in the this range.

We are designing the switching regulator output for 24V,15W. I would like to confirm that 50V rated capacitors could be used for C11uF, C2 12uF,C3 1uF ,C4 1uF between Vpos and Vss And C18 0.1uF between Vpos and Vneg as per AN956 document. We are designing the switching regulator output for 24V.

Hi,

The Document "UG333: Class 4 Isolated Evaluation Board for the Si34061" refers to Application Note 1130.
Where can I find the “AN1130: Using the Si3406/Si34061/Si34062 PoE+ and Si3404 PoE PD Controller in Isolated and Non-Isolated Designs”?

Tank you and best regards

We have designed a PoE system for 24V,15W with SI3402-B-GM controller. We have customized the design to 24V since the EVB is 5V.

We would like to review our schematics by Silabs team and provide valuable suggestions.

In the Application notes and other areas, it is said to mail your queries to PoEinfo@silabs.com 

This is what I received on sending mail

 

We are in last quarter of the design phase and we need to finalize the design. Where should I contact get the schematics review done??

Please respond asap

Does Si34061-A-GM hot swap controller supports operating supply voltage like +/- 9 V, +/- 12 V, +/- 15 V

Hi,

We are using SI3402-B-GM controller for a production of 1 million devices. We would like to clarify whether this product has support for more than 5 years. Please respond asap.

Hi,

We would like to use Si3404 for one of our PoE application. I am referring to Si3404-ISO-FB EVB schematics and BOM. But, I am not able to get the datasheet of the transformer, TOEP13-0155S1 used in the design. Could you please send the datasheet of the transformer. Or is there any alternate Coilcraft or well known Transformer which can be used?

Thanks,

Shashank

Hi,

I bought the Si34061ISOC4-KIT two weeks ago. I can't find any datasheet or information for CX-9642 made by Coilcraft. Cloud you help support the datasheet?

Is there any other transformer can compatible.

The user guides for Si34061ISOC4-KIT https://www.silabs.com/documents/public/user-guides/ug333-si34061isoc4evb.pdf

Thanks,

 

Hello,

I want to design a PoE non-isolated DC/DC converter using SI3402. The Input supply from PoE is 6.5W and the output load is maximum 3W with 3.3V output. In normal working condition, output current is around 0.2A. I am referering AN956 application note for my design. To run in continious mode for 0.2A output current, I have selected 100uH inductor. Apart from this is there any changes required?

Due to my board dimension constrain, It's difficult to have 560uF or 1000uF output capacitor, is there any other way to reduce the capacitor value. As per application note AN956, the output volatge variation for a load step of 10mA will be 0.32V for 1000uF (correct me if I am wrong), is there any way to reduce the output ripple?

AS attached file ,PD ,Pout is less than 5W, no Vout;