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?
I have implemented for firt time your PoE driver Si3402-C (isolated variant, in attachment is schematic) how ever I could not make it work correctly. The main problem is that on SWO I can see 15kHz pulses and not 350kHz. Then the output voltage is not stable and the output voltage depends on current load. It seems that the loopback is not working properly. How ever in datasheet is not closer description about the ERROUT pin so I dont know how to check if it is working properly or not. Any ideas what to check?
We are currently using Si3452 PSE controller for Power over Ethernet application. We would like to know the current status of the IC. Is it obsolete?
I need to design POE+ PSE endpoint , please suggest some IC which require minimum hardware and firmware. Also let me know if any reference circuit design any eval board available?
Si3402-C datasheet pointed to "AN1050: Si3402-C POE PD Controller Design Guide" - I don't see it on the website.
Where this app notes can be found?
I measured supply current from Si4730's.
I use QFP module that revision is D60, but current imitate by SSOP.
This datasheet is right, is it?
How can I get the EVB for Si3402B?
We are urgently need this EVB to evaluate for new project.
Also, we are studying TI, Maxim & Linear solution.
Without it, we can add Si3402B into project.
Is it any problem of Si3402B production?
Please let me know your advice.
Am currently using Si8900 to monitor mains current and voltage. So far I get both graphs for current and voltage in the range 0 ~ 1023. But am having trouble scaling down the current to measure correctly. Am assuming 512 is the 0 reference. So I get the Voltage drop at current sense resistor subtract 512 and divide by 512 so my resulting graph shows the max AC mains current graph. But the result is off by about 0.25A. need to offset this error, if it is or any ideas on how to make this feasible are much appreciated.
We are using the wide body Si8501 in our PFC boost. For some reason, as we increase the voltage during open loop testing we find that the sensor stops working. We have followed the layout guidelines as best we could. Can you provide any additional information about why this might happen?
Also, just to alleviate any confusion about the suggested layout, could you provide us with the layout files for the Si85xx test boards?
I'm looking for a recommendation, or better yet reference design, for the Si3402 using a physically small flyback transformer. My design is Class 1, 12V 2W output, and it seems like most of the available reference designs are more in the 10W range and use correspondingly sized transformers. We're pretty space-constrained, so it would sure be nice to use something smaller. Thanks.
I have a signal... +/- 12V AC square wave, 8-10kHz frequency. Depending on load, current may range from 1mA under minimal use up to 5A under short circuit conditions (before the protection kicks in, anyway).
I'd like to detect the presence of current draw on this signal (1mA). I do not need to measure current amplitude, merely measure that current is being drawn, and give a "on/off" indication to my control.
I'm currently doing so with a 50:1 CT coil and some conditioning circuitry, but I am wondering if the SI8501 might be able to do the job of the coil and some of the circuits. I'm not clear from the documentation found whether it has the required sensitivity to detect 1mA.
I have a problem in communication with ADC Si8902. It send me wrong data when I poll it for ADC conversion result in Demand mode. I put to CNFG_0 Command byte 0xE3 and get back 0xC7 with ADC_H, ADC_L bytes are zero. I read AIN2 analog channel with around 1 V on it. On other analog inputs 0 V is present. When I put to CNFG_0 Command byte 0xD3 I get back 0xC8 with ADC_H, ADC_L bytes are zero. On attached oscillograms you may see all signals on the following pins: SDO, SDI, SCLK, EN. When SDO is blue, SDI is pink, SCLK is yellow and EN is green. Images TEK0000 and TEK0001 are one oscillogram split into to image. I don't tested Si8902 in Burst mode.