LT4276 ITHB Pin in flyback mode

Question

Hello,

Am i correct in stating ITHB pin is used for control loop compensation only?

Page 12 of the component datasheet "FEEDBACK AMPLIFIER OUTPUT, ITHB" explains how the network on ITHB pin can be used to control the current threshold. What is the function of this comparator?

Also, Page 14 of the component datasheet "CONTROL LOOP COMPENSATION" sates in flyback mode this pin can alter the control loop.

Could you please give me clarification on how this pin is used in flyback mode? And more specifically how it functions internally?

Thank you in advance!

EHorsma · Accepted Answer

Hello, 
 Yes, you are correct. The ITHB voltage is inversely proportional to the sense resistor voltage when the primary gate turns off. Effectively, the lower the ITHB voltage the higher the sense voltage and thus the higher the duty cycle which sets the amount of energy delivered to the output. 
 
 In flyback mode, an external compensation network stabilizes the LT4276 and allows it to respond quickly to transient events. 
 
 Best Regards, 
 Eric)

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LT4276 ITHB Pin in flyback mode