LinkSwitch PH App Note
I am missing PI App notes on recent products compared to old ones like TOP-II, GX etc had. PH series have no app note available. e.g. more details required on following parameters :
> Resistor and Current characteristics for Rv
(also why der286 shows 4M from +ve bus only against typical schema showing along with 1M4 to Gnd ?)
> Resistor and Current characteristics for Rref (24.9k etc)
e.g. what is its behavior if its value changes a bit, say 5%
> BP pin said to have Capacitor dependent gain but no charts and details
> FB pin chart doesnt shows only normalized chart instead of uA vs Dmax values
why PH series is in Archived Products, is it going to be obsolete ?
is there replacement for PH device that have Universal input/CC/PFC/isolated/PSR all capabilities ?
Hi,
>>Typical design requires a 4M or 2M rfrom V-pin to Bulk(+). In case the line regulation slope is not flat, then a correction resistor to ground will be helpful. Use the spreadsheet to help you to calculate for the resistors.
>>As for the Rref resistor: 1% is recommended since we use this resistor to stabilize the band gap over temperature. If the application is not particular with the tight regulation then a 5% resistor is acceptable.
>>BP capacitor only sets the mode of the IC, full or reduce mode. This is a two digital level setting based on the input capacitance. Sorry for the confusion.
>>What is the information you are looking for FB pin chart,please refer to figure 5 of data sheet if this is acceptable to you. You're feedback is highly appreciated to improve the datasheet.
>>We are not planning to retire the LinkSwitch-PH product family - we have many customers like yourselves who are using the part for wide-range applications. For general applications we typically promote our LYTSwitch-4 product family which is a 2nd iteration of the LinkSwitch-PH design, but while LYTSwitch-4 is an excellent product it does not support wide-range operation. For those applications we still recommend LinkSwitch-PH.
Power integrations has many parts that have been in production for more than 10 years - so there is not threat to the continued availability of LinkSwitch-PH for your programs
The only issue for you to be aware of is that as the volume of LinkSwitch-PH being produced reduces over time, we become less able to react immediately to spikes in demand, please keep this in mind with respect to upside requirements within the typical product lead times (which should not themselves change).
I hope that this note reassures you as to the ongoing availability of this product family.
Regards,
PI-Jono