TPS92692-Q1: Dual Buck-Boost Driver

Hello,

The applications engineer who would reply to this is out of office today. He will get back to you shortly. Thanks for your patience.

Regards,

Sumeet

Hi Josnei,

Can you please give us your part list along with your requirements of input voltage range, output VLED range and output current requirement.  What is the signal for INV_FA used for?  Where is the Viadj_FAROL coming from?  You only have a total of 6.6uF at the output. How did you come up with the power stage components?

It looks like you have a fault condition so we need to figure out why.

Please give scope capture of the following signals and trigger on SS with 1mS time base:

Scope capture 1:             CH1: SS        CH2: DIM/PWM      CH3:  IADJ        CH4:  GATE

Thanks Tuan

Hi Tuan.

The circuit is already working correctly, but the current on the LEDs should be 1A and is 0,5A. If we increase the iadj pin voltage above 0.6V(0,5A) the current starts to decrease. The maximum should be 2,1V for 1,2A.

Specifications:

Vin = 9V - 16V

Vout = 13,6 (1 LED active) or 27,2(2 LEDs actives)

ILED = 1A

Hi Josnei,

We will need the scope capture of the signals above that we have requested.  Without the scope capture we can't really debug the issue.

Thanks Tuan

Fig1: Gate 

Fig2: Dim/pwm

Fig3:iadj

Fig4: SS

Hello,

We need the scope capture with all 4 signals triggering on SS as we asked for above in order to trouble shoot this.  Can you please get us that data.  Your scope capture is not what we asked for.

Thanks Tuan