ICL5102 Operation in CV/CC LED driver application

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Rakesh_Infineon
Employee
Employee
10 sign-ins 5 sign-ins First reply posted

Hi,

 

We are working on developing LED Driver for different rating ranging from 60W to 250W based on ICL5102. These drivers are basically CC/CV types.

 

In this regard, we want to understand few things,

 

1. Can we disable the BM ( Burst Mode) and operate the driver in CV mode in all load condition ( no load to full load).

2. How can we adjust the Power Limit in Burst mode and How can we calculate the Power Limit value and Power Limit frequency. Can the Power limit be made very low, say 1% of full load.

 

Regards,

Rakesh Sharma

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1 Solution
AliAsgar
Moderator
Moderator
Moderator
1000 replies posted 250 solutions authored 750 replies posted

Hi Rakesh Sharma,

1. To disable the BM, you could put a resistor between BM pin and the opto-coupler’s output, see figure below (I used ICL5102HV here, but the same for ICL5102). Design the RBM_DA such that when the opto coupler is saturated around 0.15V, the BM pin voltage is always above 0.75V. Note that the RF pin voltage is 2.5V.  RBM_DA can be calculated as:

AliAsgar_0-1669182021982.jpeg

 

AliAsgar_1-1669182034091.png

2. 

In principle, we can tune the RPL resistor to control the power transfer. During on-time of the high side MOSFET, the control injects a current (100uA) into the RPL resistor. We tune the Rpl value such that the controller in the burst mode will regulate the BM pin voltage to achieve an average voltage over the current sensing resistor = 100uA*Rsense, meaning the average power delivered is controlled and programmed by this Rpl resistor. 

However, the burst mode in ICL5102 is not easy to tune, even in  CV mode. Please disable it if they have other means to supply the rest of the circuit in the standby.

If  wide output voltage range and also wide current range is to be acheived, then I suggest to use LCC topology, instead of LLC. Of course, still stay away from the burst mode for the standby.

Best Regards,
AliAsgar

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2 Replies
AliAsgar
Moderator
Moderator
Moderator
1000 replies posted 250 solutions authored 750 replies posted

Hi Rakesh Sharma,

1. To disable the BM, you could put a resistor between BM pin and the opto-coupler’s output, see figure below (I used ICL5102HV here, but the same for ICL5102). Design the RBM_DA such that when the opto coupler is saturated around 0.15V, the BM pin voltage is always above 0.75V. Note that the RF pin voltage is 2.5V.  RBM_DA can be calculated as:

AliAsgar_0-1669182021982.jpeg

 

AliAsgar_1-1669182034091.png

2. 

In principle, we can tune the RPL resistor to control the power transfer. During on-time of the high side MOSFET, the control injects a current (100uA) into the RPL resistor. We tune the Rpl value such that the controller in the burst mode will regulate the BM pin voltage to achieve an average voltage over the current sensing resistor = 100uA*Rsense, meaning the average power delivered is controlled and programmed by this Rpl resistor. 

However, the burst mode in ICL5102 is not easy to tune, even in  CV mode. Please disable it if they have other means to supply the rest of the circuit in the standby.

If  wide output voltage range and also wide current range is to be acheived, then I suggest to use LCC topology, instead of LLC. Of course, still stay away from the burst mode for the standby.

Best Regards,
AliAsgar

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Rakesh_Infineon
Employee
Employee
10 sign-ins 5 sign-ins First reply posted

Thank you very much.

 

Regards,

Rakesh Sharma

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