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please help check the follow problems:
1、When we test 5V/3A, 9V/2A,the OCP trigger is below:
a、Expect test results:
5V/3A: 3A * (1 +10%) = 3.3 A , gain_sel : 0x16 , vref_sel : 62 ---->Vsense : 1.92*2 = 3.84V (above 10%?why)
9V/2A: 2A * (1 +10%) = 2.22A, gain_sel : 0x1B , vref_sel : 55 --->Vsense : 1.85*2 = 2.7v(above 10%?why)
b、Actual test results : whether OCP trigger threshold is OK? 10% thresold?
5V/3A:about 3.7-3.8 A
9V/2A: about 2.6 A
2、but when we test 15V/2.33A 、15V/3A, it is falied,the actual test results is small than expect value
a、Expect test results:
15V/2.33A :2.33A * (1 +10%)= 2.56 A , gain_sel : 0x16 , vref_sel : 15 -->Vsense : 1.45*2 = 2.9V (above 10%,why?)
15V/3A : 3A * (1 +10%)= 3.3 A , gain_sel : 0x16 , vref_sel : 62 --->Vsense : 1.92*2 = 3.84V (above 10% ,why?)
b、Actual test results : OCP trigger threshold is failed according to expect value above
15V/2.33A :about 1.7 A
15V/3A : about 2.2 A (but 5V/3A is OK)
Solved! Go to Solution.
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Hi,
Please follow a similar thread -
Vsense = 1.3V + (Vref_sel *10mV)
There is a linear inequality in the CSA block, therefore the above look up table you are referring to is used to correct these values.
You can further tune the values to your particular system.
Please note that error in current sensing can be due to bad layout or inaccurate Rsense values too. Please check if these are correct in your board. You can refer to our hardware design guidelines appnote - https://www.infineon.com/dgdl/Infineon-AN210403_Hardware_Design_Guidelines_for_DRP_Applications_Usin...
Pranava
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Hi,
Please follow a similar thread -
Vsense = 1.3V + (Vref_sel *10mV)
There is a linear inequality in the CSA block, therefore the above look up table you are referring to is used to correct these values.
You can further tune the values to your particular system.
Please note that error in current sensing can be due to bad layout or inaccurate Rsense values too. Please check if these are correct in your board. You can refer to our hardware design guidelines appnote - https://www.infineon.com/dgdl/Infineon-AN210403_Hardware_Design_Guidelines_for_DRP_Applications_Usin...
Pranava