TLC59711 LED Strip Driver

[24602]

Hey All,

Working on driving 12-24V LED strips from a TLC59711, I have attached a schematic

Just need a double check of the work and confirm would the Gate voltage be ok at 5V?

Need a double check if my Transistor and mosfet combination is correct.

Will be driving approximately 1A of LEDs per channel

Thanks!

[ahsrabrifat]

You can add a small gate resistor (e.g., 10Ω) in series with the MOSFET gate. It will limit the inrush current.

[Ian.M]

What inrush current?  The gate charges to turn on the MOSFET via a fricking 10K resistor!

Edit:  The driver is too slow to turn the MOSFET off except at extremely low duty cycles due to the 10K pulldown being the only discharge path for the gate charge, and inrush is limited by the gain of the SS8550 and its <0.5 mA  base current.  At 150 mA (max possible current the SS8550 can supply), the effect of a 10 ohm gate resistor would be negligible.

The PWM period is about 50us, (nom. 10MHz internal greyscale clock divided by 512, see datasheet: Figure 22. ES-PWM Operation) and I suspect the above gate drive circuit will be *far* too slow.

Edit: confirmed by simulation.  Wont work!