Video: An Overview of the Differences between the Nordic nRF51 and nRF52
About Stephanie Guimera
The Nordic nRF51-DK and nRF52 Preview DK are versatile development boards for Bluetooth® Smart, ANT, or 2.4GHz proprietary applications. The nRF52 introduces a number of new features and peripherals, bolstered by the addition of a Cortex M4F processor, which has been implemented with full debug and trace support.
Differences between the Nordic nRF51 and nRF5
nRF51 | nRF52 | ||
|---|---|---|---|
| Frequency band | 2.4GHz ISM ( 2.40000 –2.4835GHz) | Frequency band | 2.4GHz ISM (2.36000 –2.4835GHz) |
| On-air data rate | 250 kbps, 1 Mbps or 2 Mbps | On-air data rate | 1 Mbps or 2 Mbps |
| Sensitivity | 51822 : -93dBm for Bluetooth smart (-96dBm at 250kb -90dBm at 1Mbs -85dBm at 2Mbs) 51422 : -93dBm for Bluetooth smart, -90dBm ANT, -85dBm at 2Mbs, -30dBm whisper mode | Sensitivity | -96dBm for Bluetooth smart, -92.5dBm at 1Mbs ANT, -89dBm at 2Mbs, -30dBm whisper mode |
| Radio current consumption LDO at 1.8V | -16mA –TX at +4dBM output power -10.5mA –TX at 0dBm output power -13mA –RX at 1Mbs | Radio current consumption LDO at 1.8V | -15.2mA –TX at +4dBM output power, -10mA –TX at 0dBm output power, -10.4mA –RX at 1Mbs |
| Microcontroller | 32-bit ARM Cortex M0 | Microcontroller | 32-bit ARM Cortex M4F |
| Program memory | 256/128 KB Flash(40kB-180kB available for application development) | Program memory | 512kB Flash (400 kB available for application development) |
| RAM | 16/32kB | RAM | 64kB |
| Oscillators | -16MHz crystal oscillator -16MHz RC oscillator -32kHz crystal oscillator -32kHz RC oscillator (±250 ppm) | Oscillators | -32MHz crystal oscillator, -64MHz RC oscillator, -32kHz crystal oscillator, -32kHz RC oscillator (±250 ppm) |
| PPI | 16-channel | PPI | 20-channel |
| Voltage regulator | LDO (1.8 to 3.6V), LDO bypass (1.75 to 1.95V) Buck DC/DC (2.1 to 3.6V) | Voltage regulator | -LDO (1.7 to 3.6V), -Buck DC/DC (1.7 to 3.6V) |
| GPIO | 31 configurable | GPIO | 32 configurable |
| Peripherals | 10-bit ADC, RNG, Temperature sensor, RTC | Peripherals | 12-bit/200KSPS ADC, RNG, Temperature sensor |
| Timers/counters | 2 x 16 bit, 1 x 24bit, 2 x 24bit, RTC | Timers/counters | 5 x 32bit, 3 x 24bit RTC |
New Features of the nRF52
- General purpose comparator
- Event Generator Unit (EGU)
- A 2 kB direct mapped cache
Features Removed
- UICR configuration options in the nRF52 Series:
- RBPCONF - Replaced by APPROTECT
- CLENR0 - Because the nRF51 style MPU is removed, this has been removed as well
- XTALFREQ - 32 MHz crystal support only
- FWID - Uses generic NRFFW registers
- FICR configuration options in the nRF52 Series:
- CLENR0 - Because the MPU has been removed, this has been removed as well
- PPFC - Replaced by APPROTECT in UICR
- OVERRIDEEN - Not needed
- NRF_1MBIT[x] - Not needed
- BLE_1MBIT[x] - Not needed
New Peripherals
- Near Field Communication Tag (NFCT)
- Pulse Density Modulation (PDM)
- Inter-IC Sound (I2S)
- Memory Watch Unit (MWU)
- Pulse Width Modulation (PWM)
Additions and Improvements
- The radio now offers TXPOWER modes configurable from +4 dBm to -40 dBm, support for Bluetooth Low Energy packet length extension, and Fast radio ramp-up time (40 µs)
- An additional UART peripheral has been added
- An additional RTC instance has been added
- The ADC peripheral is replaced by a differential Successive Approximation Register Analog to Digital Converter (SAADC). The interface supports up to 4 differential inputs and EasyDMA for CPU offloading
- All timers now support all bit modes (8, 16, 24, and 32 bits)
- Set and Clear tasks have been added, and the number of tasks/events increased from 4 to 8
- The number of PPI groups has increased from 4 to 6. A new type of endpoint called FORK can be used to trigger an additional task from a single event endpoint
- New UICR configuration options in the nRF52 Series:
- PSELRESET - Programmable reset pin that can be multiplexed to either GPIO or RESET
- APPROTECT - Read-back protection mechanism
nRF51
The nRF51 is still a solid option, especially for existing developments in which timing is crucial.
For more information about the nRF51, nRF52, and the associated development kits, call Symmetry at (310) 536-6190 or contact us online.