Maximum output current value of PWM, TIM

[Ken Inoue]

Posted on September 16, 2017 at 18:18

Sorry for my poor English.

What is the maximum output current value of PWM using TIM? Where can I find it in the data sheet? I am using STM32F334. I am investigating whether the MOSFET can be directly driven by the PWM from the microcomputer without the gate driver.

On page 78/121 of the data sheet of STM32F334x4 STM32F334x6 STM32F334x8, the following description was given

Is IIO=8mA, 20mA the PWM maximum output current value? Which is 8 mA or 20 mA?

Best Regards,

Ken Inoue

[Tesla DeLorean]

Posted on September 16, 2017 at 18:40

It's a CONDITION, that impacts the high/low voltage outputs. ie you draw more current the further VOL gets from zero

Look at the current tables, with max per pin, and max total across all pins.

[Vangelis Fortounas · Accepted solution]

Posted on September 16, 2017 at 21:15

Hi Ken

>>>I am investigating whether the MOSFET can be directly driven by the PWM

Driving MOSFETs its not a static condition to make calculations with currents only.  MOSFET's Gate has very high Ohmic resistance. Load Capacitance of Gate, and Frequency are the main factors to decide to drive a MOSFET (also min GateSource threshold voltage must be <VCC)

In dynamic conditions like you described , the appropriate table of DataSheet to look at, is

Regards

vf

[Ken Inoue]

Posted on September 18, 2017 at 03:03

Dear

Mr./Ms. 

Clive One

Thank you for your reply. 

You mean that as more current flows, Vol increases. 

Best Regards,

Ken Inoue

[Ken Inoue]

Posted on September 18, 2017 at 03:07

Dear 

Mr./Ms. 

Vangelis Fortounas

Thank you for your reply. 

The MOSFET I use can be driven at 2.5 V, Ciss = 15 pF. And I want to operate the MOSFET at around 100 kHz. Therefore it seems possible to drive without gate driver.

Best Regards,

Ken Inoue