RTC (Real Time Clock) support

[Ishwar Sharma]

Hi,

We are looking to use nRF5340 device in our new design. We need RTC (Real Time clock) feature with this design.

Does nRF5340 device support RTC (Real Time Clock). nRF5340 supports only Real Time counters. 

Best Regards

Ishwar

[Kazi Afroza Sultana]

Hello,

1. There are different option given for RF signal (ANT) connection with Antenna. What should be the matching circuit. Is there any calculation for this. We need to use SR4W035 Antenna (2.4 GHz) with NRF52840-QIAA-R device.

 The radio match is specific for the version of the chip which should be followed in accordance with our reference design. For the antenna, the datasheet should show the required matching network. 

2.  Do we need to populate series resistors and capacitors to Ground for I2C signals.

No capacitors and series resistors are needed to ground I2C lines.

3. Should we go with High drive 0 and High drive 1 if the GPIO (output) is used with connector/Cable.

Low drive mode is the default configuration when a gpio is configured as output. 

S0S1 = "low drive" or standard drive

H0H1 = "high drive" for both driving output low and high. So, it depends on your application. It is not necessary to go with HOH1 always. 

Thanks.

Best Regards,

Kazi Afroza Sultana

[Ishwar Sharma]

Hi,

1. Can you please provide Gerber file for any Evaluation board with NRF52840-QIAA-R for reference design. 

2. How much power losses can be saved when VDDH is used in place of VDD input and internal DC-DC converter is used        with NRF52840-QIAA-R device. We will use this device for low power application (with Battery).

Best regards

Ishwar

[Kazi Afroza Sultana]

Hello,

You can use any ESD diode here.

[Ishwar Sharma]

Hi,

We are designing new board with nRF5340-QKAA device. Can you please share reference design for nRF5340-QKAA device for Schematic and PCB design where QSPI flash (external memory) is used.

Best regards

[Kazi Afroza Sultana]

You can find hardware design file here for nRF5340DK here https://nsscprodmedia.blob.core.windows.net/prod/software-and-other-downloads/dev-kits/nrf5340-dk/nrf5340-development-kit---hardware-files-2_0_0.zip .

[Ishwar Sharma]

Hi,

Thanks for sharing the information.

Need some more clarification as below.

1. What is GPIOs state during pin reset (By Pin AC31). Can we connect 3.3V on GPIO (output) during pin reset. We need this in our application. This GPIO is configured as output.

2. As per datasheet, VOH is shown minimum as VDD-0.4 V. Will it depend upon current drawn from GPIO ? If yes can you please provide graph between VOH and current drawn from GPIO.

Best regards

[Kazi Afroza Sultana]

Hello,

The original case was RTC related so it would be better if you open a new case with your queries about GPIO pin state?