LPC deep sleep mode

[lpcware]

Content originally posted in LPCWare by CroesJeroen on Mon Apr 01 05:52:48 MST 2013
Hello guys,

I wanted to know if the LPC1227 has its PWM module (coming from timer) activated in deep sleep mode?

This quote comes from the LPC1227 data sheet (page 44).

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Quote:

Deep-sleep mode
In Deep-sleep mode, the system clock to the processor is disabled as in Sleep mode. All analog blocks are powered down, except for the BOD circuit and the watchdog oscillator,which must be selected or deselected during Deep-sleep mode in the PDSLEEPCFG register. The RTC and the RTC oscillator are operating in Deep-sleep mode unless the RTC is powered down.

Deep-sleep mode eliminates all power used by the flash, analog peripherals and all dynamic power used by the processor itself, memory systems and their related controllers, and internal buses. The processor state and registers, peripheral registers, and internal SRAM values are maintained, and the logic levels of the pins remain static.

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The problem is that I can't really sort out of the peripheral is active or not because it's not a analog peripheral.

kind regards

[lpcware]

Content originally posted in LPCWare by CroesJeroen on Thu Apr 11 06:04:48 MST 2013

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Quote: tha
According to the datasheet, the IRC is typically 0.29mA and the WDosc is 0.25mA, so there is a difference in the current consumption.  So this should translate to a different power consumption.

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Hello tha, you're right.

But a current consumption of 500 µA is obtained using the WDT oscillator setup and 1.8mA when using the IRC oscillator. (both normal sleep mode)

Lot of difference. Are there peripherals that use the main clock instead of the system clock?

kind regards

[lpcware]

Content originally posted in LPCWare by tha on Wed Apr 10 15:37:30 MST 2013
According to the datasheet, the IRC is typically 0.29mA and the WDosc is 0.25mA, so there is a difference in the current consumption.  So this should translate to a different power consumption.

[lpcware]

Content originally posted in LPCWare by CroesJeroen on Wed Apr 10 13:43:59 MST 2013
bump

[lpcware]

Content originally posted in LPCWare by CroesJeroen on Fri Apr 05 13:27:15 MST 2013
Someone happened to know why the power consumption isnt the same in the next 2 cases :

main clock = IRC (12MHz), system clock = 500kHz;
main clock = WDT osc (2MHz), system clock = 500kHz.

The main clock goes to the UART0 and 1 who are disabled. The system clock is just a divided main clock.

kind regards

[lpcware]

Content originally posted in LPCWare by CroesJeroen on Fri Apr 05 13:22:46 MST 2013

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Quote: sallys21
I've been messing around with Power down mode as well, but with the LPC11u14. I believe if  you select the wdt osc for the main clock, you can still have the timer peripheral running. I'm not 100% sure on the answer, but it's worth trying.

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Hello,

Yep using the WDT osc as main Clk when sleeping. The timers are still running  but there are only external interrupt wake up causes (and RTC).

[lpcware]

Content originally posted in LPCWare by sallys21 on Mon Apr 01 14:19:17 MST 2013
I've been messing around with Power down mode as well, but with the LPC11u14. I believe if  you select the wdt osc for the main clock, you can still have the timer peripheral running. I'm not 100% sure on the answer, but it's worth trying.