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I have following question: For TOP265KG-TL is there any limit for negative startup current? We got some specification in that it is given that negative starting current limit for TOP265KG-TL is -200mA. Negative startup current means source to drain current. But in TOP265 datasheet & other application note, we have

I'm replacing a blown LNK304 in a washing machine. After replacing this component plus the 33ohm fusible resistor, I found that the output voltage is pulsing at aprox 500ms. Tested all the components in the power suply and all are ok. Mounted an external board with the same schematic as

I am using TOP268KG-TL for 4.5 W output. At 19.2V DC converter operating in CCM, But from from 40V above it is operating in DCM. Input: 19.2 - 373V DC & Universal AC input output: 12V, 5W Transformer: Primary 24; Secondary 16; Auxillary 17 ( output voltage 15); Primary magnatizing

Hi Im making 20W adaptor using INN3279C-H114 The topology is Quasi-resonant flyback and input is 220rms and out put is 5V 4A CV The R2CD snubber spec R=270K C=1000p Line R with diode=33 but when we simulate the product the IC get hotter and E-load voltage is getting up but

I designed a circuit using TNY178D and during the testing process, I found that the current limiting value for different loads is 100mA. If the load is heavy, it will enter an automatic restart state. However, its current value still turns off the MOSFET at 100mA, which is significantly different

Hello, We are experiencing an issue with the status outputs (SO) of the 2SC0435T when the driver is damaged. Specifically, faults are not being reported, and the SO is always in a high impedance state, even though the fault criteria (secondary side under voltage or overcurrent) are met. By "damaged,"

Mr. / Ms. PI engineer, currently our company is going to use inn3949cq chip to build a power output, if I want to meet the 300V-1000V input, 12V/15W output, can you tell me the relevant parameters of the transformer to meet this demand? For example, the number of primary and

Hello, I have another feature request for PI Expert. Since the company I work for only uses pre-gapped cores, it would be very useful if I could enter the desired core gap, and the remaining values were calculated with that in mind, instead of the core gap being calculated based

Our team is designing SMPS Input DC : 19.2 - 373 Volt & universal AC voltage range output : 12V , 5W We have previous design of 3W output, Which is working fine in above input range (primary inductance 240uH). This design we are modifying for 12V, 5W. Here V

How to interpret magnetic designer result regarding the core needed? There are instruction to put together E core plus Plate, but according to stack high two E cores should be used. At the same time, there is reference about nominal inductance and gap size, but there is no solution how

Hello, in the PI University Course Notes "Bringing Up a Flyback Supply for the First Time" there is a link to a PI University course named "Fixing a Flyback Supply that Does Not Deliver Full Power". The link doesn' t work any more. Is there a course note for this

Using top265 Input 19.2 to 373DC has been designed now I am trying it to extend for 5W. for higher voltage it is working fine. but at 19.2V it is not turning on and with some changes even it got tuned on then after some time input current start increasing

Hi Team, I want to know in SMPS design when feedback voltage from the output side increase beyond a certain limit then smps goes off due output overvoltage but at this condition when smps output off then feedback voltage is also zero then switching IC will sense zero feedback voltage

I designed a SW power supply using LNK6774. I want to design protection for SW power supply by Overvoltage protection function I would like to know about "External shutdown and reset options" by change resistor to comparator circuit connect base of transistor, can I do that? and can you please

Hi I'm looking some family note of INN327x series There are some technique reduce out put ripple This picture put Cap between Gnd and Vout In my opinion this cap reduce signal noise for Vout pin, so it can help reduce output voltage ripple This cap is relative for Foward

Hi All, I have designed a power supply using a TOP244 + Myrra 74030 transformer (see .pdf schematic attached). The issue is when I connect some load on the 12Vdc (less than 100mA), the voltage fall down to 7Vdc. (When no load connected, I have 12.32Vdc) Can you please help

Hello, I am trying to design a circuit using the LYTSwitch5. We almost exclusively use EF16 inductor cores, however this selection is not available in the design tool, making it difficult for me to use the tool to calculate the number of primary and secondary windings required for my purposes

In the datasheet for the LNK6663K, there are are two statements that I find conflicting. On page 3, the description for the source pin says: SOURCE (S) Pin: This pin is the power MOSFET source connection. It is also the ground reference for the BYPASS, FEEDBACK, PROGRAM and COMPENSATION pins

I have made the attached design in PI Expert online. The TVS in the RCD + Z snubber was chosen by PI Expert as a bidirectional TVS, is this correct? In the schematic VR1 is shown as a unidirectional. What is the correct type TVS to choose?

The application note says NC PIN must open This mean is NC PIN is floating or connect to GND?