Comparsion of Bluetooth Low Energy – BLE – Bluetooth Smart ICs

BLE = Bluetooth Low Energy = Bluetooth Smart = a part of Bluetooth 4.0

Competitor vers. nRF51 (left side third party / right side nRF51 for my application)

  • Switch Mode Power Supply & Linear regulators/ ditto
  • Not supported / Individual power management for all peripherals inside the IC
  • 1 x 10-bit ADC / 8/9/10 bit ADC – 8 configurable channels
  • 3 x Analogue IO / ditto and number not named
  • 3 x PWM modules / Up to 4 PWM
  • 4 x quadrature decoders / Quadrature decoder
  • 64KB RAM and 64KB ROM / 256KB flash 16KB RAM
  • Watchdog timer / state of the art inside 32-bit ARM® Cortex™ M0 32-bit CPUN
  • 32KHz & 16MHz Crystal or System Clock
  • SPI for external Flash and debug / ditto and for communication as well
  • UART / Digital interfaces -SPI Master, 2-wire, UART
  • I2C for EEPROM / external companion chips / ditto and for communication as well
  • Not supported / 16 channel CPU independent Programmable Peripheral Interconnect (PPI)
  • Not supported / 31 GPIO
  • ??? / RTC
  • ??? / Counters: 2 x16       bit, 1 x 24bit, 2 x 24bit
  • Not supported / Temperature sensor
  • 48-pin 6×6 QFN / 32-pin, 5×5  – or 56 pin , 8×8
  • Stack: BLE only / BLE, ANT, Gazel or special customized stacks like OpenBeacon
  • 1 BLE stack / 2 BLE stacks (master and slave), 1 BLE (master and slave)+ ANT, BLE plus Gazel, ANT + Openbeacon or any other combination you like

The nRF51 series offers 256kB flash in total, with 128kB available for application development. The third party names ROM only. That means you can´t upgrade the stack in the field. You can´t get an upgrade to new features. The third paty chip names no memory (flash) for own code. All mentioned features of the protocol stack are related to BLE slave only. If I am right it offers no BLE master and BLE master is necessary in a lot of applications that are not connected to a phone or laptop.
The third party can´t save the external crystal and the crystal is still one of the biggest and most expensive parts on the PCB.
The third party has the balun included. This will save 2 mm2 and some trouble to wire PCB tracks wrong. This also means that it can use single ended monopole antennas only. The two port RF interface of the transceiver can´t wired to a dipole antenna.

Worst case size of the BLE application:

  • Third party IC+ size for own memory for own code + 0 mm2 for Balun + crystal ??? mm2 = final size
  • nRF51 + 0 mm2 for memory + 2 mm2 for balun + 0 mm2 for crystal = final size

Size is not all. The best IC is useless if the is no FAE behind that will support it. Nevertheless, there is a market for all IC with BLE or BLE/ANT on this nice green planet.
If you have further questions on how to design a BLE, ANT, Gazel or any other 2400 MHz related application then just email to harald.naumann (at)

Leave a Reply

Your email address will not be published. Required fields are marked *

Blue Captcha Image