Difference between chip version 3 and chip version 2

[lakshman]

Dear Nordic, I have developed the software using development kit with latest chip version 3

nRF51422_xx_AC --->32KB RAM and 256 KB FLASH SDK ---->nRF51 SDK 9.0.0 S110 ---> 8.0.0

• IRAM base - 0x20002000
• IRAM size(32kB RAM) - 0x6000
• IROM base - 0x18000
• IROM size(256 kB Flash) - 0x28000

Then I bought a off-the-shelf BLE Nordic Module Chip version 2.

nRF51422_xx_AA --->16KB RAM and 256 KB FLASH SDK ---->nRF51 SDK 9.0.0 S110 ---> 8.0.0

• IRAM base - 0x20002000
• IRAM size(32 kB RAM) - 0x6000( i didnt configure -->IRAM size(16 kB RAM) - 0x2000)
• IROM base - 0x18000
• IROM size(256 kB Flash) - 0x28000

I have flashed Chip version 3 software directly into chip version 2. The software still working fine.

My question is ,

1. As per compatibility matrix, For chip version 2 I need to use SDK -->nRF51 SDK 6.1.0 . But I used nRF51 SDK 9.0.0 didn't use nRF51 SDK 6.1.0.
2. I didn't configured IRAM size(16 kB RAM) - 0x2000). I used same chip version 3 IRAM size(32 kB RAM) - 0x6000.

Its working fine. No issue. The software I developed based on UART. May I know the difference between Chip version 3 and Chip version 2? I am not using DC-DC & LDO but I am using low voltage mode.

Thanks and regards Lakshman,PMP,PMI-RMP

[MartinBL]

Hi

1. For the first question see the explanation in this thread.
2. For the second question, as long as your application does not require more than 16kB of RAM it will work fine on both chips