Wake up time from sleep/deep sleep

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Anonymous
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I have checked the datasheets

BCM20732S Bluetooth Low Energy SiP Module Data sheet

but i have not found any information on the wake up time from sleep/deep sleep. I basically need to know the time it take from a interrupt to the module is ready to send

I guess that i must have missed something obvious. But could someone please point me in the right direction to find this information?

Br

Mikkel

1 Solution

Wake time from deep sleep has many moving parts. Since this involves a full boot, it depends on whether you are using the module or SOC design, EEPROM or Serial flash (application + patch size), speed of NV access and 20732 or 20736/7.

For the 20732S modules, since they have an EEPROM internally, a good thumb rule is boot time* ~= 50ms + ~45mS/KByte of application + patch code (whats printed at the end of a build) assuming default I2C speed (400 KHz).

For a 20732 chip-on-board design, if the EEPROM supports it, you can increase the read speeds to 1MHz instead of the default 400 KHz. But the boot time will not reduce by 2.5 times because there is a lot of processing involved during this process. So this will be 50mS + ~30mS/KByte of app + patch code. When NV storage is serial flash, boot time ~= 50mS + 4mS/KByte of code.

For 20736/7 modules that have an EEPROM in them, boot time ~= 20mS + ~35mS/KByte of app + patch code @ 400 KHz. If I2C speed is increased to 1 MHz, this should be ~ 20mS + 23mS/KByte. If a serial flash is used for NV, boot time ~= 20mS + 900uS/KByte when SPI speed is 12 MHz.

*boot time here is the time from wake interrupt to application create call.

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MichaelF_56
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This response includes the latency for waking up from sleep: http://community.broadcom.com/message/4678#4678

But it’s missing the latency to wake from deep sleep.

I'll check to see if we can provide a discrete value for deep sleep.

Wake time from deep sleep has many moving parts. Since this involves a full boot, it depends on whether you are using the module or SOC design, EEPROM or Serial flash (application + patch size), speed of NV access and 20732 or 20736/7.

For the 20732S modules, since they have an EEPROM internally, a good thumb rule is boot time* ~= 50ms + ~45mS/KByte of application + patch code (whats printed at the end of a build) assuming default I2C speed (400 KHz).

For a 20732 chip-on-board design, if the EEPROM supports it, you can increase the read speeds to 1MHz instead of the default 400 KHz. But the boot time will not reduce by 2.5 times because there is a lot of processing involved during this process. So this will be 50mS + ~30mS/KByte of app + patch code. When NV storage is serial flash, boot time ~= 50mS + 4mS/KByte of code.

For 20736/7 modules that have an EEPROM in them, boot time ~= 20mS + ~35mS/KByte of app + patch code @ 400 KHz. If I2C speed is increased to 1 MHz, this should be ~ 20mS + 23mS/KByte. If a serial flash is used for NV, boot time ~= 20mS + 900uS/KByte when SPI speed is 12 MHz.

*boot time here is the time from wake interrupt to application create call.