TPS40211 Internal LDO

Matthias Terhorst

Other Parts Discussed in Thread: TPS40211

Team,

my customer is using the TPS40211 device as LED driver (min. quantity 100ku/y). He got stuck because of missing informations in the datasheet regarding the internal LDO (Pin BP).

Could you please provide me this additional informations:

Output Voltage of the internal LDO at Vdd=4.5V - 30V at ILDO_Out=5mA, 10mA, 15mA)
Saturation Voltage of the LDO at VDD=4.5V - 30V at different Temperatures.

This informations are very important for my customer to win the design. I would highly apprechiate if you could me this set of informations.

Thanks and Regards,

Matthias

over 14 years ago

0 Sureena Gupta over 14 years ago

TI__Intellectual 1130 points

Matthias,

I tried to look up the information, but the ic designer is unavailable. I believe I should be able to get in touch with him on Monday and get you the required information or an update.

Sureena Gupta

0 Sureena Gupta over 14 years ago in reply to Sureena Gupta

TI__Intellectual 1130 points

Matthias,

The expected drop across the LDO is estimated to be around 500mV. Hecne the output voltage of LDO can be calculated accordingly.

As for the variation in saturation voltage over temperature, please check the attached file.

Sureena Gupta

0647.40211InDropOut.pdf

0 Matthias Terhorst over 14 years ago in reply to Sureena Gupta

TI__Expert 5150 points

Sureena,

thanks for providing me this informations.

My customer would like to see a graphic with f(V_DD=4.5V to 30V, I_Out=5mA,10mA,15mA)=V_BP (x-axis: VDD=4.5V to 30V and y-axis=V_BP with I_Out=5mA, 10mA, 15mA as a parameter). In the datasheet is mentioned V_BP=7..9V which is not accurate enough for my customer.

The second question is regarding the saturation voltage of the LDO. Your attached file shows this very good for V_DD=4.5V. Could you provide me same plots for V_DD=4.5V to 30V ? My customer likes to see a graph with x-axis=V_DD=4.5V to 30V and y-axis=V_Saturation with Temp as parameter.

Thank you very much and Regards,

Matthias