Ble receive and send collisions

RE: Ble receive and send collisions

Kenneth — Thu, 22 Aug 2019 06:42:00 GMT

Hi,

I didn't think of you may be using rev 1 (C), new production is based on rev 2 (D):
https://infocenter.nordicsemi.com/pdf/pcn_111_v1.0.pdf?cp=3_0_2_0

So if you place an order for new samples of the nRF52840 today, then you should get the latest revision 2 (D) where this issue is fixed.

Best regards,
Kenneth

RE: Ble receive and send collisions

hongpal — Thu, 22 Aug 2019 03:55:39 GMT

I found out Errata and our chip is QIAA-Cx0.

We used DCDC in high voltage mode.

So I knew Errata 202 and 197. We will change from DCDC to LOD.

Today we are going to test on LDO.

Our device also is not start up after reset.

I think it is due to Errata 202.

What do I do to solve this problem ? We want to use DCDC.

RE: Ble receive and send collisions

Kenneth — Wed, 21 Aug 2019 11:06:01 GMT

You need to look at the battery and decoupling on VDDH. I expect that the voltage on VDDH drop and this cause VDD to not able to output 1.8V anymore. So you need a bigger battery or more decoupling on VDDH input.

Best regards,
Kenneth

RE: Ble receive and send collisions

hongpal — Wed, 21 Aug 2019 09:03:37 GMT

We tested. But I found the rest.

How to solve this problem ? Give me a direction.

RE: Ble receive and send collisions

hongpal — Tue, 20 Aug 2019 08:51:43 GMT

Today, I have found out voltage drop below 1.7V on VDD.

Our REGOUTO is set on 0, so VDD is 1.8 V.

I think it would be below. Therefore we are going to set REGOUTO to 1.

So Vdd is 2.1V. I will report that after we will test.

RE: Ble receive and send collisions

Kenneth — Mon, 19 Aug 2019 11:48:05 GMT

It is very likely some kind of excessive current draw that cause a ripple on VDD, so please try to measure this ripple on VDD. For test you may also try a steady power supply (bench supply) when testing outdoor instead of battery.

Best regards,
Kenneth

RE: Ble receive and send collisions

hongpal — Mon, 19 Aug 2019 11:17:23 GMT

No I don't measured VDD on a oscilloscope because I don't experience resetting indoor. The reset only occur outdoor test.

Our design is Config.4

RE: Ble receive and send collisions

Kenneth — Mon, 19 Aug 2019 11:00:03 GMT

Have you measured VDD on a a oscilloscope to check if there are large dips in VDD when you experience reset?

Also, what power supply option are you using in your design?
https://infocenter.nordicsemi.com/topic/ps_nrf52840/ref_circuitry.html?cp=3_0_0_6_2