Stand-alone Bluetooth Smart module

OLS425 Bluetooth low energy moduleThe stand-alone Bluetooth low energy (Bluetooth Smart) modules OLS425 and OLP425 are compact modules that support ultra low power consumption and are suitable for applications using coin cell batteries. They come complete with embedded Bluetooth stack and offer solder castellations for visual inspection as well as Apple iOS and Google Android connectivity.

The OLS425 embeds firmware with the u-blox Low Energy Serial Port Service for replacing serial cables or accessing UART devices using Bluetooth low energy technology.

The OLP425 is tailored for those who wish to embed a customer developed application and/or Bluetooth services/attributes on top of the integrated software stack and tools. The stack and tools include object code with the latest Bluetooth low energy protocol stack supporting multiple connections, sample projects and applications covering an extensive set of profiles with source code.The OLP425 is a stand-alone product with no additional hardware required since it offers several mounting options including temperature sensor, accelerometers and LEDs. The OLP425 sample code package includes sample projects for accessing the LEDs, temperature sensor and accelerometers. The OLP425 offers GPIO, SPI, I2C, and UART interfaces as well as analog inputs.

The modules are fully Bluetooth qualified and provide modular radio type approvals for the US, Europe, Japan and Canada (FCC, R&TTE, MIC, IC). They are also compliant with EMC, Safety and Medical standards. The operating temperature range is –40°C to +85°C.


  • Bluetooth v4.0 with Bluetooth low energy (Bluetooth Smart)
  • Serial port application firmware for UART serial data
  • MCU for customer developed applications
  • GPIO / SPI / I2C / UART interface
  • Options for integrated sensors and LEDs
  • u-blox Low Energy Serial Port Service
  • Apple iOS and Google Android connectivity

Click here for high resolution image.


  • Bluetooth v4.0 (Bluetooth low energy)
  • Range:
    • 50 m, internal antenna
    • 200 m, external antenna
  • Output power:
    • 3 dBm, internal antenna
    • 6 dBm, external antenna
  • Receive sensitive level: –91 dBm
  • Throughput: 26 kbps (max)
  • Temperature sensor1 (optional):
    • Accuracy 0.5°C (max) from 0°C to +65°C
    • Accuracy 1.0°C (max) from -40°C to +125°C
  • Accelerometer1 (optional):
    • ±2g / ±4g / ±8g / ±16g dynamically selectable. 2 independent programmable interrupt generators for free-fall and motion detection 6D/4D orientation detection
  • Other sensors1:
    • 4 pcs through hole solder points for other sensors (2 GPIO or 1 ADC)
  • Embedded software:
    • Bluetooth stack
    • Serial port application2
    • Customer implemented Bluetooth low energy profiles, services & attributes1
  • GATT based service:
    • u-blox Low Energy Serial Port Service2
  • Profile roles:
    • OLS425: Peripheral Role
    • OLP425: Central Role, Peripheral Role
  • Max. number of slaves:
    • OLS425: 1
    • OLP425: 3
  • Configuration tools2:
    • AT commands
    • Serial Port Toolbox (Windows-based SW)
  • Development environment1:
    • IAR Embedded Workbench for 8051 (not included)
  • Security: Simple Pairing
  • Android connectivity
  • iOS connectivity




1 Applies to OLP425 only
2 Applies to OLS425 only

  • Electrical data:
    • RF power supply 2.0 to 3.6 VDC
    • Power consumption: 0.4 μA @ 2.0V (min.), 10 mA @ 2.0V (average Tx)
  • Interfaces:
    • SPI1, I2C1, UART logic level
  • Supported baud rates:
    • OLS425: 57.6 kbps (max.)
    • OLP425: 115.2 kbps (max.)
  • Flow control: CTS/RTS (hardware) or none
  • GPIO pins:
    • OLS425: 11
    • OLP425: 18
  • ADC channels1: 4
  • LEDs1: 2 (optional red and green LEDs)
  • U.FL antenna connector (external antenna version only)
  • Package:
    • Dimensions:
      • 14.8 x 22.3 x 3.2 mm (internal antenna)
      • 14.8 x 22.3 x 2.8 mm (external antenna)
      • 14.8 x 22.3 x 4.2 mm (JST connector)
    • Weight: 1.5 g
    • Mounting:
      • Mounting holes
      • Machine mountable
      • Solder edge pads with castellations
  • Environmental data, quality & reliability:
    • Operating temperature –40°C to +85°C (JST version: -25°C to +85°C)
  • Certifications and approvals:
    • Type approvals:
      • Europe (ETSI R&TTE)
      • US (FCC/CFR 47 part 15 unlicensed modular transmitter approval)
      • Canada (IC RSS)
      • Japan (MIC - formerly TELEC)
    • Medical Electrical Equipment: IEC 60601-1-2
    • Bluetooth Qualification: v4.0"Bluetooth Smart" is the same as "Bluetoot low energy", a low power, lower data rate version of Bluetooth originally introduced for the healthcare, fitness, security, and home entertainment industries.




Product Documentation

cB-OLP425 App


  • View the Bluetooth low energy demo video that shows the use of the u-blox Low Energy Serial Port Service in an industrial setting with a robot, a computer, an iPhone and the modules OLS426, OBS421, and OLP425.

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