Other Parts Discussed in Thread: TPS23758, TPS23755
Tool/software:
Hi expert,
This is Uni-trend FAE Ryker, recently Uni-trend is evaluating TPS23758 in latest thermal camera project. And they need TI help to design the suitable transformer spec to use TPS23758 consistently and then they can contact LinkCom to produce. The background and support need as below:
- Background: Uni-trend have previously developed several models using the TPS23758: UTi591A, UTi594A, etc. They are currently experiencing the following issues:
- Uni-trend products are equipped with adapters for 12V/1A. On the UTi591A model, the TPS23758 is stable. On the UTi594A model, a small number of samples occasionally experience power down to the TPS23758 output 5V supply.
- The main difference between the UTi591A and the UTi594A is the power consumption. The UTi591A consumes less than 4.5W and the UTi594A consumes less than 5.5W. R&D attempts to use the 24V adapter to supply power can solve the problem.
- After consulting the E2E before, the response was:
The applied transformer is suitable for input voltages from 36 - 57V. When used at 12 volts and with a 6:1 ratio, you need a 74% duty cycle. The maximum duty cycle range of the TPS23755 is 75% - 80%. If the potential error of the transformer is taken into account, the inversion mode may not provide sufficient duty cycle, especially in heavy duty peak current mode. The output line of a 12V adapter may be long considering the end customer's actual application environment. In this case, the voltage input to the device side may actually be around 11V.
- Support need:
- In order to completely solve this problem, we want to ask Ti experts to help redefine the transformer turn ratio and other parameters based on the architecture of the LDT1018-50 (Ti custom transformer), so that the transformer can meet the input voltage of 8 (or even lower) -57V. If the design of this parameter is difficult, the output power can be appropriately reduced (such as down to 10W), to ensure that our products adapt to the customer's 12V adapter, can be stable operation. After Ti has designed the transformer, Uni-trend will find LinkCom to manufacture and validate it.
Best Regards,
Ryker
