topic Sleep mode current increases when i2c wakeup source used in LPC Microcontrollers

Sleep mode current increases when i2c wakeup source used

VasuVirpariya — Tue, 26 Dec 2023 14:37:43 GMT

I used the SDK's example (power_mode_switch_lpc) for exercising power-down mode. I added support for i2c wakeup in power-down mode. The issue that we are facing is as per below.

1) Entering power-down mode from the UART menu.

2) Power down mode current = 14 uA.

3) Wake up from the I2C.

4) Entering power-down mode from the UART menu.

5) Power down mode current = 67 uA.

I have attached the project below. What could be going wrong in second time?

Re: Sleep mode current increases when i2c wakeup source used

xiangjun_rong — Wed, 27 Dec 2023 06:20:26 GMT

Hi,

Because you use I2C as slave to wake-up the LPC, I suppose that you activate SRAM block, as you know that each SRAM block requires a lot power.

Pls check the SRAM block power up or down in PDRUNCFG register for your different configuration

BTW, can you tell us the part number of LPC?

XiangJun Rong

Re: Sleep mode current increases when i2c wakeup source used

VasuVirpariya — Wed, 27 Dec 2023 09:09:31 GMT

It is LPC804. I am using the LPCxpresso804 kit.

What I am wondering is why first time it is consuming 14uA current and the second time onward it is taking 67uA. The attached firmware can be run on the LPCxpresso804 kit.