BLUENRG-LP datasheet(8/72 Pages) STMICROELECTRONICS

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Private key accelerator (PKA) including:

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Elliptic curve Diffie-Hellman (ECDH) public-private key pair calculation accelerator

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Based on the Montgomery method for fast modular multiplications

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Built-in Montgomery domain inward and outward transformations

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AMBA AHB lite slave interface with a reduced command set

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Cyclic redundancy check calculation unit (CRC)

1.5

RF subsystem

The BlueNRG-LP embeds an ultra-low power radio, compliant with Bluetooth® Low Energy (BLE) specification.

The BLE features 1 Mbps and 2 Mbps transfer rates as well as long range options (125 kbps, 500 kbps), supports

multiple roles simultaneously acting at the same time as Bluetooth® Low Energy sensor and hub device.

The BLE protocol stack is implemented by an efficient system partitioned as follows:

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Hardware part: BlueCore handling time critical and time consuming BLE protocol parts

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Firmware part: Arm® Cortex®-M0+ core handling non time critical BLE protocol parts

1.5.1

RF front-end block diagram

The RF front-end is based on a direct modulation of the carrier in TX, and uses a low IF architecture in RX mode.

Thanks to an internal transformer with RF pins, the circuit directly interfaces the antenna (single ended

connection, impedance close to 50 Ω). The natural band pass behavior of the internal transformer simplifies

outside circuitry aimed at harmonic filtering and out of band interferer rejection.

In transmit mode, the maximum output power is user selectable through the programmable LDO voltage of the

power amplifier. A linearized, smoothed analog control offers a clean power ramp-up.

In receive mode, the automatic gain control (AGC) can reduce the chain gain at both RF and IF locations, for

optimized interferer rejections. Thanks to the use of complex filtering and highly accurate I/Q architecture, high

sensitivity and excellent linearity can be achieved.

BlueNRG-LP

RF subsystem

DS13282 - Rev 2

page 8/72

BLUENRG-LP 데이터시트(PDF) 8 Page - STMicroelectronics