WEBENCH® Tools/CC3220: can it drive 3.3V for GPIO

Ashwin Lakshman

Intellectual 470 points

Part Number: CC3220

Tool/software: WEBENCH® Design Tools

Hi,

we are considering CC3220SF and CC3220moda for one of our project. and we have the below 2 questions

1. CC3220moda:

> Can the module CC3220moda drive 3.3V for the GPIO pins, VBAT1(pin 37) and VBAT2(pin40) is connected to 2.8V (output of a buck converter)

> Can the module interface a 1.8V GPS chip over a UART or should we need a level shifter.

2. CC3220SF

> Can CC3220SF drive 3.3V for the GPIO pins when used in wide voltage mode. (Pin 10, 54, 44, 39, 37 set to 2.8V)

> We see that VDD pin 9 and 56 is powered from Pin 43 which is DCDC_DIG_SW. whats sets this voltage? is there an internal DC DC converter Buck/Boost? How is the digital IO voltage set?

> Can the module interface a 1.8V GPS chip over a UART or should we need a level shifter.

over 7 years ago

0 Kevin Allen18 over 7 years ago

TI__Mastermind 45206 points

Hi Ashwin,

What digital logic levels does the GPS module support?

Regarding our part, the minimum digital logic level is 2.4V, so you will probably need a level shifter between your GPS chip and the UART.

The GPIOs are driven by the VDD voltage, so if it's 2.8V you won't be able to drive 3.3V.

Best,
Kevin

0 Ashwin Lakshman over 7 years ago in reply to Kevin Allen18

Intellectual 470 points

Hi Kevin,

Thanks for the reply.
GPS uses 1.8V, so we will use a level shifter.

I agree GPIO's are driven by VDD voltage, on CC3220SF, Pin 9(VDD_DIG1) and Pin 56(VDD_DIG2) are the VDD pins which is set from pin 43.
we apply our 2.8V to pin 10,54,44,39,37,47. Can we consider 2.8V as our VDD, or is it the voltage that appears on pin 9 and pin56 to be considered as Vdd, if so then what is the voltage that appears on pin 9 and pin56. (if we need to worry about it)

0 Vincent Rodriguez over 7 years ago in reply to Ashwin Lakshman

TI__Mastermind 28285 points

Ashwin,

Digital output levels for various voltages are listed in our Datasheet on page 31

.http://www.ti.com/lit/ds/symlink/cc3220.pdf

The voltage you supply to those pins is considered you VDD voltage, not what is present on pin 9 and pin 56.

Regards,

Wi-Fi

Wi-Fi forum

WEBENCH® Tools/CC3220: can it drive 3.3V for GPIO