BLUENRG-1 datasheet(16/173 Pages) STMICROELECTRONICS

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Functional details

BlueNRG-1

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DocID028866 Rev 1

3.3

Memories

The memory subsystem consists of 160 KB Flash memory and two banks of 12 KB ultra-

low leakage static RAM blocks.

The 160 KB Flash memory is available to the user and can be accessed per 32-bit for read

access and per 32-bit for write access (with 4x32-bit FIFO).

The access to the static RAM can be as bytes, half words (16 bits) or words (32 bits).

A 12 KB RAM block is always in retention mode, whereas the second 12 KB RAM block is

switchable and can be put in retention mode according to the user needs.

3.4

Power management

The BlueNRG-1 integrates both a low dropout voltage regulator (LDO) and a step-down

DC-DC converter to supply the internal BlueNRG-1 circuitry.

The BlueNRG-1 most efficient power management configuration is with DC-DC converter

active where best power consumption is obtained without compromising performances.

Nevertheless, a configuration based on LDO can also be used, if needed.

A simplified version of the state machine is shown below.

Figure 4: BlueNRG-1 power management state machine

3.4.1

States description

3.4.1.1

Preactive state

The preactive state is the default state after a POR event.

In this state:



All the digital power supplies are stable.



The high frequency clock runs on internal fast clock RC oscillator (16 MHz).



The low frequency clock runs on internal RC oscillator (32.768 kHz).

BLUENRG-1 Datasheet(PDF) 16 Page - STMicroelectronics