RF-Star RF-BM-ND04C User manual

RF-BM-ND04C and RF-BM-ND04CI nRF52810
Bluetooth 5.0 Low Energy Module
Version 1.1
Shenzhen RF-star Technology Co., Ltd.
May 26th, 2023
All rights reserved. Those responsible for unauthorized reproduction will be prosecuted.

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 1 of 27
1 Device Overview
1.1 Module Series
There is a series of RF-BM-ND04C(I) Bluetooth 5.0 Low Energy modules. All of them are based on Nordic nRF52810
SoC. Those modules are pin-to-pin compatible with each other as well.
Table 1. Module Series of RF-BM-ND04(I)
Model
Antenna Output
Mode
Chip Model
TX
Power
FLASH
RAM
Protocol
ND04C
PCB onboard
nRF52810
+4 dBm
192 KB
624 KB
BLE5.0
ND04CI
IPEX connector/Half-
hole RF pin
1.2 Description
RF-BM-ND04C and RF-BM-ND04CI are RF modules based on Nordic BLE SoC nRF52810 with ARM® Cortex®-M4 32-
bit processor. It integrates a 32.768 kHz and a 32 MHz crystal, an LC filter, an antenna matching and a meander line
inverted-F PCB antenna or IPEX connector respectively. It supports Bluetooth 5.0 LE, including the high-speed 2 Mbps
feature and ANT and 2.4 GHz proprietary protocols for simple programming. The module has numerous digital
peripherals and interfaces such as PDM, PWM, UART, SPI, I2C and 12-bit ADC. It features low power consumption,
small size, robust connection distance, and rigid reliability. 1.27-mm pitch stamp stick package for easy assembling and
cost-effective PCB design.
1.3 Key Features
•RF features
- Bluetooth 5.0 low energy
- ANT
- 2.4 GHz proprietary
•TX power: -20 to +4 dBm
•ARM® Cortex®-M4 32-bit processor, 64 MHz
•Supply voltage range 1.7 V ~ 3.6 V
•Memory
- 192 KB flash
- 24 KB RAM
•Support for concurrent multi-protocol
•Peripherals
- 12-bit, 200 ksps ADC
- 29 GPIOs
- 4-channel PWM
- Digital microphone interface (PDM)
- SPI master/slave
- I2C master/slave
- UART (CTS/RTS)
•Programmable peripheral interconnect (PPI)
•Quadrature decoder (QDEC)
•AES HW encryption
•Dimension: 24.8 mm x 15.0 mm x 2.3 mm
•Certificates of RF-BM-ND04C: SRRC, FCC, RoHS

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 2 of 27
1.4 Applications
•Mouse and keyboard
•Mobile HID
•Remote controls
•Wearables
•Virtual reality headsets
•Health and medical
•Industrial lighting
•Retail
•Commercial
•Beacons
1.5 Functional Block Diagram
RF-BM-ND04C
RF-BM-ND04CI
Figure 1. Functional Block Diagram of RF-BM-ND04C(I)
nRF52810
GPIO
Debug
Reset
PCB
Antenna
LC Filter
Power Supply
1.7 V ~ 3.6 V
Antenna
Matching
32.0 MHz
32.768 kHz
nRF5281
0
GPIO
Debug
Reset
LC Filter
Power Supply
1.7 V ~ 3.6 V
Antenna
Matching
32.0 MHz
32.768 kHz
IPEX
Connect
Half-
hole
Antenna
Switch

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 3 of 27
1.6 Part Number Conventions
The part numbers are of the form of RF-BM-ND04C(I) where the fields are defined as follows:
Figure 2. Part Number Conventions of RF-BM-ND04C(I)
RF
BM
ND
Company Name
RF-STAR
Wireless Type
Bluetooth Module
Chipset Manufacturer
Nordic Semiconductor
-
-
04C(I)
Module Version
Without I: nRF52810 PCB Version
With I: nRF52810 IPEX Version

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 4 of 27
Table of Contents
1 Device Overview............................................................................................................................................................. 1
1.1 Module Series ..................................................................................................................................................... 1
1.2 Description............................................................................................................................................................ 1
1.3 Key Features ....................................................................................................................................................... 1
1.4 Applications.......................................................................................................................................................... 2
1.5 Functional Block Diagram .............................................................................................................................. 2
1.6 Part Number Conventions.............................................................................................................................. 3
Table of Contents................................................................................................................................................................ 4
2 Module Configuration and Functions ...................................................................................................................... 6
2.1 Module Parameters........................................................................................................................................... 6
2.2 Module Pin Diagram ......................................................................................................................................... 7
2.3 Pin Functions....................................................................................................................................................... 7
3 Specifications .................................................................................................................................................................11
3.1 Recommended Operating Conditions .....................................................................................................11
3.2 Handling Ratings..............................................................................................................................................11
3.3 Power Consumption .......................................................................................................................................11
4 Application, Implementation, and Layout.............................................................................................................12
4.1 Module Photos..................................................................................................................................................12
4.2 Recommended PCB Footprint....................................................................................................................12
4.3 Schematic Diagram.........................................................................................................................................13
4.4 Reference Design............................................................................................................................................14
4.5 Antenna................................................................................................................................................................15
4.5.1 Antenna Design Recommendation ..............................................................................................15
4.5.2 IPEX Connector...................................................................................................................................16
4.5.3 Antenna Output Mode Modification..............................................................................................17
4.5.4 External Antenna Design Recommendation of the Half-Hole ANT Pin..........................17
4.6 Basic Operation of Hardware Design ......................................................................................................18
4.7 Trouble Shooting..............................................................................................................................................19
4.7.1 Unsatisfactory Transmission Distance........................................................................................19
4.7.2 Vulnerable Module..............................................................................................................................20
4.7.3 High Bit Error Rate .............................................................................................................................20
4.8 Electrostatics Discharge Warnings ...........................................................................................................20

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 5 of 27
4.9 Soldering and Reflow Condition.................................................................................................................20
5 Optional Package Specification ..............................................................................................................................22
6 Certification .....................................................................................................................................................................24
6.1 SRRC ...................................................................................................................................................................24
6.2 FCC.......................................................................................................................................................................24
6.3 RoHS ....................................................................................................................................................................25
7 Revision History ............................................................................................................................................................26
8 Contact Us.......................................................................................................................................................................27

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 6 of 27
2 Module Configuration and Functions
2.1 Module Parameters
Table 2. Parameters of RF-BM-ND04C(I)
Chipset
nRF52810
Supply Power Voltage
1.7 V ~ 3.6 V, recommended to 3.3 V
Frequency
2402 MHz ~ 2480 MHz
Transmit Power
-20.0 dBm ~ +4.0 dBm (typical: 0 dBm)
Receiving Sensitivity
-96 dBm
Data Rate
1 Mbps, 2 Mbps
Power Consumption
4.6 mA peak current in TX (@ 0 dBm)
4.6 mA peak current in RX
GPIO
29
Crystal
32 MHz, 32.768 kHz
RAM
24 KB
Flash
192 KB
Package
SMT Packaging (1.27-mm half-hole pitch stamp stick)
Frequency Error
±20 kHz
Dimension
24.8 mm x 15.0 mm x 2.3 mm
Type of Antenna
RF-BM-ND04C: PCB antenna
RF-BM-ND04CI: IPEX connector / half-hole RF ANT pin
Operating Temperature
-40 ℃ ～ +85 ℃
Storage Temperature
-40 ℃ ～ +125 ℃

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 7 of 27
2.2 Module Pin Diagram
RF-BM-ND04C RF-BM-ND04CI
Figure 3. Pin Diagram of RF-BM-ND04C(I)
2.3 Pin Functions
Table 3. Pin Functions of RF-BM-ND04C
Pin
Name
Chip Pin
Pin Type
Description
1
GND
GND
GND
GND
2
VCC
VCC
Power
Power supply 1.7 V ~ 3.6 V, Recommend to 3.3 V
3
P21/RST
P0.21
nRESET
Digital I/O
General purpose I/O
Reset, active low. Internal pullup.
4
P22
P0.22
Digital I/O
General purpose I/O
5
P23
P0.23
Digital I/O
General purpose I/O
6
P24
P0.24
Digital I/O
General purpose I/O
7
P25
P0.25
Digital I/O
General purpose I/O

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 8 of 27
8
P28
P0.28/AIN4
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
9
P29
P0.29/AIN5
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
10
P30
P0.30/AIN6
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
11
P26
P0.26
Digital I/O
General purpose I/O
12
P27
P0.27
Digital I/O
General purpose I/O
13
P02
P0.02/AIN0
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
14
P03
P0.03/AIN1
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
15
P04
P0.04/AIN2
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
16
P05
P0.05/AIN3
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
17
P06
P0.06
Digital I/O
General purpose I/O
18
P07
P0.07
Digital I/O
General purpose I/O
19
P08
P0.08
Digital I/O
General purpose I/O
20
P09
P0.09
Digital I/O
General purpose I/O
21
P10
P0.10
Digital I/O
General purpose I/O
22
P11
P0.11
Digital I/O
General purpose I/O
23
P12
P0.12
Digital I/O
General purpose I/O
24
P13
P0.13
Digital I/O
General purpose I/O
25
P14
P0.14
Digital I/O
General purpose I/O
26
P15
P0.15
Digital I/O
General purpose I/O
27
P16
P0.16
Digital I/O
General purpose I/O
28
SWDIO
SWDIO
Digital I/O
Serial wire debug I/O for debugging and
programming

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 9 of 27
29
SWCLK
SWDCLK
Digital input
Serial wire debug clock input for debugging and
programming
30
P17
P0.17
Digital I/O
General purpose I/O
31
P18
P0.18
Digital I/O
General purpose I/O
32
P19
P0.19
Digital I/O
General purpose I/O
33
P20
P0.20
Digital I/O
General purpose I/O
Table 4. Pin Functions of RF-BM-ND04CI
Pin
Name
Chip Pin
Pin Type
Description
1
GND
GND
GND
GND
2
ANT
ANT
ANT
Antenna output interface. Default as none use.
3
GND
GND
GND
GND
4
GND
GND
GND
GND
5
VCC
VCC
Power
Power supply 1.7 V ~ 3.6 V, Recommend 3.3 V.
6
P21/RST
P0.21
nRESET
Digital I/O
General purpose I/O
Reset, active low. Internal pullup.
7
P22
P0.22
Digital I/O
General purpose I/O
8
P23
P0.23
Digital I/O
General purpose I/O
9
P24
P0.24
Digital I/O
General purpose I/O
10
P25
P0.25
Digital I/O
General purpose I/O
11
P28
P0.28/AIN4
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
12
P29
P0.29/AIN5
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
13
P30
P0.30/AIN6
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
14
P26
P0.26
Digital I/O
General purpose I/O
15
P27
P0.27
Digital I/O
General purpose I/O
16
P02
P0.02/AIN0
Digital I/O
General purpose I/O

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 10 of 27
Analog input
SAADC/COMP input
17
P03
P0.03/AIN1
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
18
P04
P0.04/AIN2
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
19
P05
P0.05/AIN3
Digital I/O
Analog input
General purpose I/O
SAADC/COMP input
20
P06
P0.06
Digital I/O
General purpose I/O
21
P07
P0.07
Digital I/O
General purpose I/O
22
P08
P0.08
Digital I/O
General purpose I/O
23
P09
P0.09
Digital I/O
General purpose I/O
24
P10
P0.10
Digital I/O
General purpose I/O
25
P11
P0.11
Digital I/O
General purpose I/O
26
P12
P0.12
Digital I/O
General purpose I/O
27
P13
P0.13
Digital I/O
General purpose I/O
28
P14
P0.14
Digital I/O
General purpose I/O
29
P15
P0.15
Digital I/O
General purpose I/O
30
P16
P0.16
Digital I/O
General purpose I/O
31
SWDIO
SWDIO
Digital I/O
Serial wire debug I/O for debugging and programming
32
SWCLK
SWDCLK
Digital input
Serial wire debug clock input for debugging and
programming
33
P17
P0.17
Digital I/O
General purpose I/O
34
P18
P0.18
Digital I/O
General purpose I/O
35
P19
P0.19
Digital I/O
General purpose I/O
36
P20
P0.20
Digital I/O
General purpose I/O

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 11 of 27
3 Specifications
3.1 Recommended Operating Conditions
Functional operation does not guarantee performance beyond the limits of the conditional parameter values in the table
below. Long-term work beyond this limit will affect the reliability of the module more or less.
Table 5. Recommended Operating Conditions of RF-BM-ND04C(I)
Items
Condition
Min.
Typ.
Max.
Unit
Operating Supply Voltage
Battery Mode
1.7
3.3
3.6
V
Operating Temperature
/
-40
+25
+85
℃
Environmental Hot Pendulum
/
-20
+20
℃/min
3.2 Handling Ratings
Table 6. Handling Ratings of RF-BM-ND04C(I)
Items
Condition
Min.
Typ.
Max.
Unit
Storage Temperature
Tstg
-40
+25
+125
℃
Human Body Model
HBM
±4000
V
Moisture Sensitivity Level
3
Charged Device Model
±1000
V
3.3 Power Consumption
Table 7. Power Consumption
Event
Average Current
Testing Conditions / Remark
Sleeping
1.23 µA
EN disconnected
Broadcast
70.33 µA
Broadcast cycle: 200 ms
Broadcast
28.38 µA
Broadcast cycle: 500 ms
Broadcast
14.02 µA
Broadcast cycle: 1000 ms
Broadcast
7.64 µA
Broadcast cycle: 2000 ms
Broadcast
3.49 µA
Broadcast cycle: 5000 ms
Connection
64.72 µA
Connection cycle: 50 ms
Connection
33.80 µA
Connection cycle: 100 ms

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 12 of 27
4 Application, Implementation, and Layout
4.1 Module Photos
RF-BM-ND04C RF-BM-ND04CI
Figure 4. Photos of RF-BM-ND04C(I)
4.2 Recommended PCB Footprint
RF-BM-ND04C

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 13 of 27
RF-BM-ND04CI
Figure 5. Recommended PCB Footprint of RF-BM-ND04C(I) (mm)
4.3 Schematic Diagram
RF-BM-ND04C

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 14 of 27
RF-BM-ND04CI
Figure 6. Schematic Diagram of RF-BM-ND04C(I)
4.4 Reference Design
Note: EN falling edge active.
RF-BM-ND04C

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 15 of 27
Note: EN falling edge active.
RF-BM-ND04CI
Figure 7. Reference Design of RF-BM-ND04C(I)
4.5 Antenna
4.5.1 Antenna Design Recommendation
1. The antenna installation structure has a great influence on the module performance. It is necessary to ensure the
antenna is exposed and preferably vertically upward. When the module is installed inside of the case, a high-quality
antenna extension wire can be used to extend the antenna to the outside of the case.
2. The antenna must not be installed inside the metal case, which will cause the transmission distance to be greatly
weakened.
3. The recommendation of antenna layout.
The inverted-F antenna position on PCB is free-space electromagnetic radiation. The location and layout of the
antenna is a key factor to increase the data rate and transmission range.
Therefore, the layout of the module antenna location and routing is recommended as follows:
（1）Place the antenna on the edge (corner) of the PCB.

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 16 of 27
（2）Make sure that there is no signal line or copper foil in each layer below the antenna.
（3）It is best to hollow out the antenna position in the following figure to ensure that the S11 of the module is
minimally affected.
Figure 8. Recommendation of Antenna Layout
Note: The hollow-out position is based on the antenna used.
4.5.2 IPEX Connector
RF-BM-ND04CI module is integrated the IPEX version 1 antenna seat, the specification of the antenna seat is as follow:
Figure 9. Specification of Antenna Seat

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 17 of 27
The specification of the IPEX wire end is as follow:
Figure 10. Specification of IPEX Wire
4.5.3 Antenna Output Mode Modification
RF-BM-ND04CI has two antenna output modes: IPEX connector output and stamp half-hole antenna output (ANT pin,
see pin function table for details).
The default delivery is IPEX connector mode. Under IPEX connector mode, C1 is off and C2 is welded. If you would like
to change to half-hole antenna output mode, please disconnect C2 and weld C2. The locations of C1 and C2 (8 pF) are
shown in the figure below.
Figure 11. Antenna Output Mode Change
4.5.4 External Antenna Design Recommendation of the Half-Hole ANT Pin
1. A Π-type matching circuit is reserved for the antenna, and 50 Ω impedance control is performed on the RF traces.

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 18 of 27
The traces are as short as possible, and 135° or arc traces are used as much as possible. No vias are used to
change layers. More GND vias are placed around the RF traces.
Figure 12. Reference Design of the External Antenna
Figure 13. Reference Design of the External Antenna Traces
2. The RF trace width and copper-clad spacing can be calculated by SI9000 software, and the impedance is controlled
to 50 Ω according to the actual board thickness, number of layers, plate, dielectric thickness, dielectric constant,
copper thickness, line width, line spacing, and solder mask thickness.
Example: FR4 is a double-layer board with a thickness of 1.0 mm. Through calculation, the width of the trace is
0.8254 mm, and the spacing between traces and copper is 0.22 mm.
Figure 14. SI9000 Impedance Calculation Diagram
4.6 Basic Operation of Hardware Design
1. It is recommended to offer the module with a DC stabilized power supply, a tiny power supply ripple coefficient, and
reliable ground. Please pay attention to the correct connection between the positive and negative poles of the power

RF-BM-ND04C(I)
www.szrfstar.com V1.1 - May, 2023
Shenzhen RF-star Technology Co., Ltd. Page 19 of 27
supply. Otherwise, the reverse connection may cause permanent damage to the module;
2. Please ensure the supply voltage is between the recommended values. The module will be permanently damaged
if the voltage exceeds the maximum value. Please ensure a stable power supply and no frequently fluctuated voltage.
3. When designing the power supply circuit for the module, it is recommended to reserve more than 30% of the margin,
which is beneficial to the long-term stable operation of the whole machine. The module should be far away from the
power electromagnetic, transformer, high-frequency wiring, and other parts with large electromagnetic interference.
4. The bottom of the module should avoid high-frequency digital routing, high-frequency analog routing, and power
routing. If it has to route the wire on the bottom of the module, for example, it is assumed that the module is soldered
to the Top Layer, the copper must be spread on the connection part of the top layer and the module, and be close
to the digital part of the module and routed in the Bottom Layer (all copper is well-grounded).
5. Assuming that the module is soldered or placed in the Top Layer, it is also wrong to randomly route the Bottom Layer
or other layers, which will affect the spurs and receiving sensitivity of the module to some degrees;
6. Assuming that there are devices with large electromagnetic interference around the module, which will greatly affect
the module performance. It is recommended to stay away from the module according to the strength of the
interference. If circumstances permit, appropriate isolation and shielding can be done.
7. Assuming that there are routings of large electromagnetic interference around the module (high-frequency digital,
high-frequency analog, power routings), which will also greatly affect the module performance. It is recommended
to stay away from the module according to the strength of the interference. If circumstances permit, appropriate
isolation and shielding can be done.
8. It is recommended to stay away from the devices whose TTL protocol is the same 2.4 GHz physical layer, for
example, USB 3.0.
4.7 Trouble Shooting
4.7.1 Unsatisfactory Transmission Distance
1. When there is a linear communication obstacle, the communication distance will be correspondingly weakened.
Temperature, humidity, and co-channel interference will lead to an increase in communication packet loss rate. The
performances of ground absorption and reflection of radio waves will be poor when the module is tested close to the
ground.
2. Seawater has a strong ability to absorb radio waves, so the test results by the seaside are poor.
3. The signal attenuation will be very obvious if there is a metal near the antenna or the module is placed inside the
metal shell.
4. The incorrect power register set or the high data rate in an open-air may shorten the communication distance. The
higher the data rate, the closer the distance.
5. The low voltage of the power supply is lower than the recommended value at ambient temperature, and the lower