TPS92692-Q1: schematic review

Ivy,

How  can you expect me to review a design without any input and output specifications or switching frequency?

Hi Daniel,

The Vin and Vout have been shown on the picture, Vin=12V (9-16V), Vout=33V(Vout max =40V).

I'm sorry to have missed the switching frequency information, which is 390 kHz.

Regards,

Ivy

The Voltage RANGE was not shown in the picture and Vout is set to 35V in the picture, not 33V. This is important information for me to evaluate the design. I will get to it ASAP

Hi Daniel,

The vout range is 30-37V, the 33V is the normal value, 40V is the maximum limit value.

Regards,

Ivy

Thanks!

I looked through the configuration of the components and they look good so far... I have a few questions below:

is it okay that this is on a public forum?

What is the output power? Current set point? 

Hi Daniel,

The vout range is 30-37V, the output current can be divided into two situations:
For DRL, the external PWM frequency is 5KHz, the duty cycle is 100%, and the current is 170mA

For position lighting, the external PWM frequency is 5KHz, the duty cycle is 17%, and the current is 29mA

The problem now is that the LED will blink when the duty cycle is in the 30%-70% range, the customer wants to know what could be the cause of the flickering.

Regards,

Ivy

Hi Ivy,

I thought this was a preliminary schematic evaluation... I need wave forms when I have to diagnose an issue post-production. However, 5Khz is extremely fast for PWM dimming, we typically recommend under 1KHz to ensure proper resolution and accuracy.

If you would like me to thoroughly diagnose this issue, I will need the following wave forms:

Preliminary design phase:

In the event you are asking me a general question before your customer has begun designing their project,

I need to know the input/ output requirements and switching frequency.

Post design testing phase:

If your customer has an issue with their design and their pcb is already constructed.

I need the following wave forms as well as the input/ output requirements and switching frequency:

Inductor current
Switch node voltage
fault pin if it is present on the IC
Input voltage
Output voltage
Register settings (if applicable)

any other wave forms that provide me information on the issue that is occurring

I am also more than happy to arrange a meeting with you so we can solve this issue in a timely fashion.

I look forward to assisting you and your customer further.

Best,
Daniel