how to control driver automatically

51 posts / 0 new

Dear sir,

 

we hav now one led driver ckt using LINK SWITC PH family, we developed it for using out side street light application. but now we need to operate the light unit with automatically on/off using LDR, so how to include this control circuit to my main driver..is it possible???

pls replay

with regards

 

Pradeep M

Kerala

India 

  Pls refer to page 3 on the datasheet for Remote ON/OFF and EcoSmart. You can basically build a circuit here using the Vpin and your LDR to control the on-off of the device. 

dear sir,

 

i can't understand ur suggestion, ur mentioned "PAGE3" is in which data sheet..pls expalin..becaz the matter is very urgent

 

regards

 

Pradeep

page 3 of LinkSwitch-PH datasheet. http://www.powerint.com/sites/default/files/product-docs/linkswitch-ph_family_datasheet.pdf

 

The V pin can be used to do remote-on off. If you pull it down below 1V, the unit will turn-off. Configure your LDR with a comparator to do this function.

sir

can u suggest a comparator with LDR circuit to shut down the LNK408, tht wil very help me to control the driver automatically

 

waiting for ur valuable support 

 

regards

Pradeep  

Pls see attached circuit idea using TL431. You just need to adjust the values based on your LDR.

dear sir,

very thanks for ur support, me have one doubt regarding the ckt , there three zeners r used 5.1V, 10V and one more..so wht wil be its value. Q1 is TL431 as for ur mail. and wht will be the value of resistor conncted in first to the bridge??

waiting for ur replay

 regards

 

Pradeep M 

There are two zeners, 5.1 and 10V. The resistor in series with the 10V zener from the bridge should be adjusted to provide the bias currents for the circuit. You can start with a 100k value for low line designs. You can also use a low current shunt regulator like LMV431 which requires less operating current, and replace the bjt with a 2n7000 fet. Hope you get the idea.

very very thanks sir, understand ur suggestion, and me have one more help frm ur side. now am developed one led driver ckt for 15-25W range using LINK swith PH/ LNK408. now we want to develop two more models thts watts ranges from 25 to 80W, required spec as input line 90-300VAC/50Hz, need input PF of  0.9< and THD of 15>. pls suggest ur IC for making this model. we want to develop economoc and easily manufacturable model. suggest ur circuit and send as ur mail.am using Osram LED of LUWW5AM , which is suitable for to load 350mA to 700mA range.

waiting for ur valuable suggestion and replay

my native place is in kerala/country -India, so pls advice me whre i get technical support classes from PI

regards

 

Pradeep M 

Forr 25 to 80W power and requires power factor, you can use LinkSwitch-PH ICs. You can contact our sales office in Bangalore, there are technical FAEs  in that office which can answer your questions regarding your design.

http://www.powerint.com/en/company/sales-information/worldwide-sales-support-locations

You can also look at the design selector site for design examples with complete engineering reports which will be useful for you for jumpstarting your designs.

http://www.powerint.com/en/applications/led-driver-ics/led-design-selector

 

sir,

can u suggest any link swicth PH ic for meeting my requirements..availability is important..i need 25 to 90 wattage ratings ..suggest  the ics and its rating, after i can refer the detail for the perticular ic and contact them..waiting for ur valuable suggestion and support..

 

regards

 

Pradeep M 

You can use LNK407-410 for nondimming or LNK417-LNK420 for dimming. There is an output power table on LinkSwitch-PH datasheet page 1 for your device selection based on output power and input voltage range http://www.powerint.com/sites/default/files/product-docs/linkswitch-ph_family_datasheet.pdf

sir,

 

if i hav one boubt regarding the above, in my area the input AC flactuation is very more..so i think while using smd component its a chance to damage my driver easily [ street light application, operated @ mains 230V/50Hz ] so i wil plan to change the smd by thru hole components...the price and size wil be increasing som...so wht is ur suggestion regarding this matter..and giv me the advabntage disadvantage over this

 

waiting for ur replay

Regards

Pradeep M Nair 

SMD should be ok as long as you take into consideration the fluctuations in the line and incorporate it in your design of the smd components. Thru-hole or discrete can be an advantage if you have the space and reduce it to single sided board, because basically you can reduce the process in production that probably will save you some cost.

dear sir

 

in my ckt LNK 408 /22W design the following components r too heated

 

IC LNK 408 , MUR 860  nd transformer

am using ur Vpin cut off ckt as parally..can u sugest how to recover the prblm, if u need my ckt nd design i wil send u the same shortly

 

with regrads

pradeep

my no +919495574670 

Pls send your design docs

For the devicem increasing the BP supply current can reduce the temperature, for the output diode, check your derating, if hot you can use a next bigger size diode, for the transformer, check your winding CMAs and make sure the core doesnt saturate.

dear sir

 

can u send ur personnel mail id pls 

 

 

 

Pradeep

No need. If you dont want to discuss the problem in this forum, pls contact the local PI sales office in your area and the local FAE can help you for your technical inquiries.

Regards

sir,

  i wil send my details shortly 

dear sir

 

we identified the heating problem, ie we hav connecting the Vpin cut off ckt [ tht given by u for ur previous mail] the load current incresing that is 750 mA became 1.20A..we develop the Vpin cutoff ckt using mosfet 2N7000, how to overcome the difficulty in LNK408.

pls replay us

pradeep 

dear sir

 

still am waiting for ur replay regarding the heating problem. my project wrk now stopped due to that.

 

pls advice me why the load current became increase whn connecting the vpin cutoff ckt

pls replay

 

 

Pradeep

pls attached your schematic with values you are using so I can better understand your problem.

dear sir,

if am attaching my design details of orcad file can u correct with the design as per schematic, the ckt containg driver of 25 w lnk 408 based and its vcc shut down ckt, due to som of my personnel prblms i can't follow up this project in time. in my ckt am not using smd components only using thru hole components.

waiting for ur replay 

 

Pradeep

 

 

no attachment

i can't attach the details becaz attachments became failed, giv me ur any id pls

 

my attachments containing .max file and .pdf files

 

waiting for ur replay 

 

 

Pradeep

Im not sure why your attachment doesnt work. Please try it again

dear sir

 

i developed the schematic of 80w led driver using ur PI expert software, but i need to cahnge the ckt with 15 to 85 w @ variable range, i don't know how to change the setting for the custome design. can u help me whether am upload the details??? 

 

 

 

sir

 

here am attaching my ckt, pls redesign it to 15 to 80w ranges/also convert the o/p txr to economical design

 

waiting for ur replay

 

bye 

Its not clear on what you meant by variable range, which is variable?, the output voltage or the current?

 

LinkSwitch-PH or LYTswitch devices are constant current controllers, so the output current is nearly constant for a specified design. The only variable is the output voltage, since LED voltage have small changes due to tolerance or manufacturing spread. With the variation in output voltage, the IC maintains the output current constant . The output voltage range that the IC will maintain a CC depend on the operating IFB.  Normally, the recommended IFB for the nominal output voltage is 150uA. The output voltage range then should give IFB of 100uA to 200uA.

 

15-80W is too big of a range  of power for a single LinkSwitch-PH design.

if it is possible to chnge my design to 40 to 80 range for the following ckt LNK420??

if possiblegiv me the design values 

Again for a particular design or output current, the range of output voltage it can deliver is on line 8 and 9 of the PIXls spreadsheet. VO_MIN to VO_MAX. To get the power range you multuply Iout with these two values.

dear sir

 bunow me hav on driver LNK 419 ic based of 30W, but its input THD is belo 30% how to reduce it by <10%. i  know  it can be reduced by adding two more resistors and caps frm VCC to FB pin. how its posible nd ..which values can be used for that..pls advice??

 

 

Pradeep

you can refer to the DER below for improving THD

http://www.powerint.com/sites/default/files/PDFFiles/der344.pdf

br

dear sir,

 

we hav one ac driver @ ordinary operation, we tried it to auto on/off operation using ur ckt. but its not working properly.so pls advice any other methord for making the driver by auto on/off using LDR. 

 

 

 

 

 

Pradeep

We dont have an app note for turning off lytswitch using ldr right now. Well post it once we have developed and tested it.

pls check the attachments

 

thts i got it frm thid forum, advice how to correct it 

 

 

Pradeep

Well post once weve tested and developed this circuit using LDR

dear sir

 

we take vcc frm driver i/p section and connect the vpin to switching mosfet, for addine this external ckt the o/p current is changed ie increasing. so how we can produce the vcc for this ckt nd how to provide isolation b/w these two ckt 

 

 

Pradeep

The output current will change if the transistor connected on V-pin has some leakage when it is supposed to be off. For this you need to figure out how you can avoid this leakage.

pls giv me a gud solution for making a desk to dawn control LED driver [ LNK PH ] using LDR, if u hav any schematic layout ets , pls share us ur idea 

 

 

Well share it with you once its available. As of now we dont have a tested solution yet.

so wht wil we do for next???????

What is the part number of the ldr you are using? If possible give me the schematic of your current turn-off circuit with values and well go from there.

 

 

We dont have an app note for turning off lytswitch using ldr right now. Well post it once we have developed and tested it.

sir,

 

i wil send my details to u soon, whn wil u available on online chat... 

 

Pradeep

sir,

 

wht wil be the minimum signal voltage for apply to Vpin to shut down the IC ????

 

regards

 

Pradeep

0.5 V minimum. You can see it on the remote on-off threshold of the datasheet.

dear sir,

we r using TNY264P ic in our circuit, now we know that it became obsolete. so pls advice which is the equivalent for this part?? and what cahnges can be need in the circuit for replacing the same.

dear sir

we r using TNY264P in our circuit, but nw we came to know that it became obsolete. so advice which ic is equivalent for this part??and advice what changes can be need for replacing the same.

What are your Input and Outpower specifications for the current design using TNY264P? Send us the current transformer design spec's? Probably there will be a lay out change?

Also go through the below device datasheet, whether you can use the below part:

http://ac-dc.power.com/sites/default/files/product-docs/tinyswitch-iii_family_datasheet.pdf

 

Regards,

PI-KSAN