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LM3552SDEV: Obsolete alternate request

Part Number: LM3552SDEV
Other Parts Discussed in Thread: LM3553, TPS54201, LM2751, TPS61165, TPS61161A, TPS61150A

Hi All,

We have been used LM3552 led driver in our project ,but currently LM3552 has went obsolete.

we need to have driven two led as series which forward voltage is 3.1V and current 160mA . Input voltage is 5V.

We found alternate part LM3553 but it is I2C control.in our project The torch and flash mode is controlled by GPIO pin from the camera module.we don't want I2C control one.

Could any one please help us on this issue?.

Thanks,

Jabir m.

  • Hi Jabirali,

        You can check whether TPS54201 can support your requirement , since TPS54201 is a synchronous buck LED driver and can support from 4.5V to 28V, 1.5A maximum output current. That may be a good choice.

    Regards

    Sean

  • Hi Sean,

    We need independent Torch and Flash mode in our project, can you suggest any other  alternate LED driver  which meet  our requirement .

    Thanks,

    Jabirali m

  • Hi jabirali m,

         I'm sorry that our flash/torch LED driver are all with I2C interface. but you can check LM2751, you can use two of LM2751 for such kind of application.

    Regards

    Sean

  • Dear Sean,

    Thanks for your reply!

    I am working with Mr.Jabir for this LED driver design and we have decided to use the single channel TPS61165 LED driver. For the torch and flash modes, We have planned to use the NFET circuitry shown in the image below to have two different modes. Kindly let us know whether there is something we need to know reg. the use of this circuitry.

    Also, I am considering the TPS61161A part as well which seems like a package equivalent(WSON) to TPS61165 with few rating/functionality differences namely lack of one-wire interface , lower voltage/current rating etc. However, our application requires a LED drive current of 160mA in flash mode & as per the calculation TPS61161A seems to be capable but the efficiency vs led current graphs in the datasheet only seem to show upto 50mA which makes me bit doubtful. My intention here is to keep TPS61161A chip as a backup option for TPS61165 as it looks to be a close match with identical package. Kindly let me know on this.

    In addition, I would like to know on the availability/life time information for both of the above parts. The TI webpage for the each part did show as "ACTIVE" but an exact figure would be more helpful for me.

    Will appreciate a quicker reply on this.

    Thanks,

    N.Balaji

     

  • Hi N.Balaji,

         For the application to use the FET to change the total resistance between "ISET" and gnd, we suggest when you change the Q1 turn on or turn off, we recommend to disable the TPS61165 and when the Q1 state is stable, then enable the Q1, that can make sure the total system is stable.

        For TPS61161A and TPS61165, we don't have the plan to EOL or NRND, so don't worry about to use those devices.

    Regards

    Sean

  • Dear Sean,

    Thank you for the reply!

    Please find my inline replies.

         For the application to use the FET to change the total resistance between "ISET" and gnd, we suggest when you change the Q1 turn on or turn off, we recommend to disable the TPS61165 and when the Q1 state is stable, then enable the Q1, that can make sure the total system is stable.

    [Balaji] : I went through the datasheet of TPS61150A 2-ch LED driver. I could see that on-the-fly brightness variation using FET scheme is possible(please refer image below). Based on this, We understand that brightness dimming using FET could be done when LED driver is enabled and operational.

    May I know whether the concern regarding the LED driver stability with regards to use of FET circuitry is limited to TPS61165?  If so, can you suggest any other stable brightness adjustment scheme which is possible with two GPIO signals(PWM /I2C/1-wire interface not possible)? 

    Kindly let me know on this asap.

    Thanks,

    N.Balaji

  • Hi Sir,

        Yes understand the concern, My main concern is that what's the PWM frequency that used on Q1, it should not be very much. If the frequency is low,  I think it is ok. But I suggest you do some experiment with your application specs and MOSFET.

    Regards

    Sean

  • Dear Sean,

    Thanks for your reply!

    We do not use PWM or high frequency to control Q1 FET. Its just ON and OFF based on the brightness modes. So I hope we are good with this. Please Let us know.

    However, as you mentioned we will be doing experiments with the configuration practically.

    I wanted to know regarding the usability of TPS61161A for our application which i mentioned in previous post. I have quoted my query below for your reference. Please let us know this as well.

    "Also, I am considering the TPS61161A part as well which seems like a package equivalent(WSON) to TPS61165 with few rating/functionality differences namely lack of one-wire interface , lower voltage/current rating etc. However, our application requires a LED drive current of 160mA in flash mode & as per the calculation TPS61161A seems to be capable but the efficiency vs led current graphs in the datasheet only seem to show upto 50mA which makes me bit doubtful. My intention here is to keep TPS61161A chip as a backup option for TPS61165 as it looks to be a close match with identical package. Kindly let me know on this."

    Thanks,

    N.Balaji

  • Hi Balaji,

        The main difference between TPS61161A and TPS61165 is the input voltage range. Both should be ok for your application.

    Regards

    Sean