16 Channel Adjustable Constant Current LED Driver

MLang.11 · ‎2021-12-10

I'm looking for a drop in replacement for the TI TLC5926IPWPR LED driver.

It's 16 channel constant current LED driver. Max current is set via an external resistor, but we can also adjust the current via the SPI interface.

Does ST have this as well? I do not need error detection feature. Just need to adjust the current via SPI bus.

5mA to 61mA output current.

I looked at the STP16CPC26 but it uses the ~OE pin as a PWM input to adjust the current, so it's not a constant current source unless the max current trips. If I'm understanding that right. I need to be able to adjust the current and still have it be a constant current source.

Peter BENSCH · ‎2021-12-13

OK, I think I got it now.

However, the three suggestions are not PWM controllers, but linear current sources with central setting of the segment currents, which can only be switched on or off via SPI. Correct, it would then also be possible to control the currents centrally via PWM.

Otherwise, the only variant that can be set via SPI would be the LED1642GW that you can take a look at. However, the circuit would have to be adapted a little, and of course the control program, so that you can use it.

Regards

/Peter

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Peter BENSCH · ‎2021-12-11

Welcome, @MLang.11, to the community!

you could check:

Good luck!

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/Peter

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MLang.11 · ‎2021-12-13

Peter,

Unfortunately, those are all PWM controllers. You can not adjust the constant current limit via the SPI interface. They require the use of the ~OE pin as a PWM input to adjust the brightness.

Do you have any that are true constant current controllers? Where you can adjust the current via the SPI interface?

Peter BENSCH · ‎2021-12-13

OK, I think I got it now.

However, the three suggestions are not PWM controllers, but linear current sources with central setting of the segment currents, which can only be switched on or off via SPI. Correct, it would then also be possible to control the currents centrally via PWM.

Otherwise, the only variant that can be set via SPI would be the LED1642GW that you can take a look at. However, the circuit would have to be adapted a little, and of course the control program, so that you can use it.

Regards

/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

MLang.11 · ‎2021-12-13

Thank you Peter, that is what I'm looking for. It will indeed need some adaptation, but with the supply chain as it is, I'll take firmware changes any day to support another part.

Now I just have to find the lead time on this guy.