suitable MCU or DSP for UPS/inverter application

[--BawA--]

HEllo , I am designing a Pure sine wave inverter, Plz suggest me any MCU or DSP which satisfy the following needs
1) Independent pwm,
2) easily available
3) not too much costly
4) simulation software should be easily available

 

[memarian]

Hi,

Currently i'm using STM32F303 in my inverter project. it has everything you need. ST released a new chip from ST32F3 family (STM32F334) specially for inverter/switching power supply and similar applications.

check this :

https://www.st.com/web/en/catalog/m...?icmp=ln1820_pron_pr1_jun2014&sc=stm32f334-pr

Good Luck!

 

[--BawA--]

Thanx memarian, Could you please answer some of my questions
1) what is the cost of above mcu?
2) Which simulation software are you using?
3) Are you using any development board for the same?

 

[memarian]

Thanx memarian, Could you please answer some of my questions
1) what is the cost of above mcu?
2) Which simulation software are you using?
3) Are you using any development board for the same?

Hi,


1) Price : it very much depends on which distributor you buy your chips. for Example i use STM32F303CBT6 in my design , Mouser Electronics Sell it for 7.57$ (quantity < 10) , but Wuhan P&S sell it for 4.41$, but if i want to buy less than 10 Chips, i'll buy them from Mouser, because the shipping cost is much lower to my location and total order+shipping cost will be cheaper than Wuhan. so i think you should check different distributors and calculate price with shipping cost.
Also STM32F3 Series have many models with different peripherals and very different prices, so you should select you microcontroller carefully.if you search you can even find less than 2$ models of STM32F3 Series , but you should check and see if their peripherals satisfy your project requirements.

2) i'm not using any simulation software for the microcontroller, but i use Orcad Cadence for simulating the Analog sections. BTW,STM32F3 Series are ARM Cortex M4 with FPU and i didn't find any simulation software that could simulate ARM Cortex-M4 Core with all peripherals and interrupts ... etc.

3) No, but i tested my initial code on STM32F3DISCOVERY and after checking the result, i designed my own board.

STM32F3DISCOVERY is very chip (10~15 USD) with many capabilities.
check this : https://www.st.com/web/catalog/tools/FM116/SC959/SS1532/PF254044

Also check ST Site, they have several development boards.

Good Luck!

 

[--BawA--]

Anyone , please tell me " How many independent pwm signal can be generated from stm32f303" ?
I'll be needing 7 pins for pwm ,is it possible for this mcu?

 

[memarian]

Anyone , please tell me " How many independent pwm signal can be generated from stm32f303" ?
I'll be needing 7 pins for pwm ,is it possible for this mcu?

Hi,

Yes, it's possible.

STM32F303 has these timers :

TIM1 & TIM8 : 2 Advanced timers upto 6ch PWM each with dead-time and full control.

TIM2 & TIM3 & TIM4 : General Purpose Timers with PWM Capability.

TIM 15 & TIM16 & TIM17 : 16 bit Auto reload Timers with PWM capability and more.

You can use these 8 timers for PWM (fully independent). Some of them can have several channels (with complementary), so there is a lot more than 7 pin for PWM.
check Chapters 16 ,17 & 18 from STM32F3 Reference Manual :
https://www.st.com/web/en/resource/technical/document/reference_manual/DM00043574.pdf

There is only one thing : Select Your STM32F303 model carefully, it has 48 & 64 & 100 pin models. in All models each pin could have several functions, that you choose in your program. in 48 pin or 64 pin models you may have some difficulty to configure your mcu. for more information Check Tabel 11 in STM32F303 Datasheet.

 

[--BawA--]

but on website it's written that stm32f303 has only 6 channel pwm ..

 

[memarian]

but on website it's written that stm32f303 has only 6 channel pwm ..

Hi,

could you please send the link on ST.com about this?

Because currently i'm using STM32F303 with more than 6 PWM outputs in my design!! (currently i'm using 8 PWM outputs from different timers : TIM1 , TIM8 , TIM2,TIM4 & TIM15)

Please check the reference manual and datasheet carefully , because as far as i know, each of TIM1 & TIM8 could have up to 6 PWM Channels, and there are other timers and they could have PWM output too!

 

[--BawA--]

my requirement is
DC DC converter 2 pwm pins in pushpull fashion @75KHz
DC AC inverter 4 pwm pins in full bridge topology @ 25KHz
charger 1 pwm pin in forward mode converter @ 20KHz

can it be fulfilled by stm32f303?

 

[memarian]

my requirement is
DC DC converter 2 pwm pins in pushpull fashion @75KHz
DC AC inverter 4 pwm pins in full bridge topology @ 25KHz
charger 1 pwm pin in forward mode converter @ 20KHz

can it be fulfilled by stm32f303?

Hi,

Yes , it's possible.

1) DC-DC Converter 2 Pins @ 75 KHz: You can use TIM1 or TIM8 for this purpose easily. with correct configuration you only need one of them. You can also use TIM15.
2) DC-AC converter 4 Pins @ 25KHz : You have 2 ways for this , using TIM1 and TIM8 together or one of them (Different configuration).
3) 1 pin forward converter @20 KHz : you can use anyone of these timers : TIM2 , TIM3 , TIM4, TIM16, TIM17.(or TIM15)

But please check Reference manual and select your timers and configuration you want to use,and after that select your STM32F303 Model from Datasheet, because if you choose your stm32f303 model incorrectly (some of 48 pin models have limited capabilities), you may have encounter some troubles setting up your chip.