Wurth Elektronik OPHELIA-I User manual

OPHELIA-I REFERENCE MANUAL
2612011022000
VERSION 1.0
JANUARY 27, 2022

Revision history
Manual
version
HW
version Notes Date
1.0 1.0 • Initial release December
2021
Ophelia-I reference manual version 1.0 © January 2022
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Abbreviations
Abbreviation Name Description
BER Bit Error Rate
DC Direct Current
ESD Electrostatic
Discharge
EV (Board) Evaluation (Board) Ophelia-I populated on motherboard with USB
interface for test and evaluation purpose.
FCC
Federal
Communications
Commission
GND Ground Ground signal level that corresponds to 0 V.
GPIO General Purpose
Input/Output
IC Integrated Circuit
I/O Input/output Pinout description
LDO Low Dropout Low dropout voltage regulator
Bluetooth LE Bluetooth Low
Energy
PCB Printed Circuit
Board
RAM Random Access
Memory
RF Radio frequency Describes wireless transmission.
RSSI Receive Signal
Strength Indicator
The RSSI indicates the strength of the RF signal. Its
value is always printed in two’s complement notation.
SMA SubMiniature
version A
SWD Serial Wire Debug
UART
Universal
Asynchronous
Receiver
Transmitter
Allows the serial communication with the module.
VDD Voltage Drain
Drain Supply voltage
VSWR Voltage Standing
Wave Ratio
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Contents
1 Introduction 5
1.1 Operational description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Blockdiagram................................... 6
1.3 Orderinginformation............................... 6
2 Electrical specifications 7
2.1 Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 Powerconsumption................................ 8
2.3.1 Static................................... 8
2.4 Radiocharacteristics............................... 9
2.5 Pincharacteristics ................................ 10
3 Pinout 11
4 Antenna connection 13
4.1 On-boardPCBantenna ............................. 13
4.2 Externalantenna................................. 13
5 Custom firmware 14
5.1 Customerfirmware................................ 14
5.2 Contact for firmware requests . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6 Firmware flashing using the production interface 15
7 Design in guide 16
7.1 Advice for schematic and layout . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.2 Dimensioning of the micro strip antenna line . . . . . . . . . . . . . . . . . . 18
7.3 Antennaconnection ............................... 19
7.3.1 Simple short using internal antenna . . . . . . . . . . . . . . . . . . 20
7.3.2 22 pF coupling capacitor using internal antenna . . . . . . . . . . . 21
7.3.3 22 pF coupling capacitor using external antenna . . . . . . . . . . . 22
7.4 Antennafinetuning................................ 23
7.5 Antennasolutions ................................ 23
7.5.1 Wireantenna .............................. 23
7.5.2 Chipantenna .............................. 24
7.5.3 PCBantenna .............................. 24
7.5.4 Antennas provided by Würth Elektronik eiSos . . . . . . . . . . . . 25
7.5.4.1 2600130021 - Himalia - 2.4 GHz dipole antenna . . . . . . . . 25
8 Reference design 26
8.1 EV-Board ..................................... 27
8.1.1 Schematic................................ 27
8.1.2 Layout .................................. 28
9 Manufacturing information 29
9.1 Moisture sensitivity level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
9.2 Soldering ..................................... 29
9.2.1 Reflowsoldering ............................ 29
9.2.2 Cleaning................................. 30
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9.2.3 Potting and coating . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
9.2.4 Othernotations ............................. 31
9.3 ESDhandling................................... 31
9.4 Safety recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
10 Physical specifications 33
10.1 Dimensions.................................... 33
10.2 Weight....................................... 33
10.3 Lightsensitivity .................................. 33
10.4 Moduledrawing.................................. 34
10.5 FootprintWE-FP-4+ ............................... 35
10.6 Antennafreearea ................................ 35
11 Marking 36
11.1 Lotnumber .................................... 36
12 Information for explosion protection 37
13 References 38
14 Important notes 39
14.1 General customer responsibility . . . . . . . . . . . . . . . . . . . . . . . . . 39
14.2 Customer responsibility related to specific, in particular safety-relevant ap-
plications ..................................... 39
14.3 Best care and attention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
14.4 Customer support for product specifications . . . . . . . . . . . . . . . . . . 39
14.5 Productimprovements.............................. 40
14.6 Productlifecycle ................................. 40
14.7 Propertyrights .................................. 40
14.8 General terms and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 40
15 Legal notice 41
15.1 Exclusionofliability................................ 41
15.2 Suitability in customer applications . . . . . . . . . . . . . . . . . . . . . . . 41
15.3 Trademarks .................................... 41
15.4 Usagerestriction ................................. 41
16 License terms 43
16.1 Limitedlicense .................................. 43
16.2 Usageandobligations .............................. 43
16.3 Ownership..................................... 44
16.4 Firmwareupdate(s)................................ 44
16.5 Disclaimer of warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
16.6 Limitationofliability................................ 44
16.7 Applicable law and jurisdiction . . . . . . . . . . . . . . . . . . . . . . . . . . 45
16.8 Severabilityclause ................................ 45
16.9 Miscellaneous................................... 45
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1 Introduction
1.1 Operational description
The Ophelia-I is a radio module for wireless communication between devices such as control
systems, remote controls, sensors etc. The module is based on the radio chipset nRF52805
from Nordic Semiconductor and is meant as hardware-only module: no firmware is imple-
mented on the module. It is customer’s responsibility to develop the firmware for the module
fulfilling the requirements of the specific application.
Since the Ophelia-I does not integrate any firmware, no radio certification is provided for
this radio module. Nevertheless, the Ophelia-I is ready for CE/RED, FCC, IC and TELEC.
The Ophelia-I hardware platform mounting Bluetooth®LE firmware has been tested within
the certification of Proteus-e [3]. Test reports can be requested from BDM or support.
Depending on the firmware developed and flashed on the module, a wide range of applica-
tions is possible. For example, the module can be configured to communicate with external
sensors, can use security configurations, and can be optimized for low power consumption.
Ultra small dimensions of 7 x 9 mm including a strongly miniaturized PCB antenna make
the Ophelia-I ideal for small form factor design. It is possible to connect an external antenna,
in case higher radio ranges are required.
For firmware development and all functional topics, please refer to the documentation and
resources available for the nRF52805 chipset [1].
For firmware customization topics, please refer to chapter 5 and to the Bluetooth®5.1 ra-
dio module Proteus-e [3].
Figure 1: Ophelia-I
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1.2 Block diagram
Ophelia-I
Shielding
Wireless MCU
High accuracy
crystal
RF Filter & 50Ω
matching
UART,
Reset, GPIO,
SWD
Power
supply
DCDC voltage
regulator
ARM Cortex M4,
Flash, RAM
Radio core,
2.4GHz
50Ω port to λ/4
antenna
Antenna
external wiring
according to
reference design
Figure 2: Block diagram of the module
1.3 Ordering information
WE order code Description
2612011022000 Ophelia-I Module, Tape & Reel
2612019022001 Ophelia-I Evaluation Board
Table 1: Ordering information
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2 Electrical specifications
Unless otherwise stated, the values specified are measured on the evaluation board of the
Ophelia-I with T=25°C, VDD=3 V, f=2.44 GHz, internal DC-DC converter in use.
Many electrical specifications depend on the specific firmware flashed on the
module. For example specifications with Bluetooth®LE 5.1 firmware, please
refer to the Proteus-e user manual [3]. For chipset specifications, please refer
to documentation from Nordic [1]
2.1 Recommended operating conditions
Description Min. Typ. Max. Unit
Ambient temperature -40 25 85 °C
Supply voltage (VDD) 1.8 3 3.6 V
Supply rise time (0V to ≥1.7V) 60 ms
Table 2: Recommended operating conditions
The on-chip power-on reset circuitry may not function properly for rise times
longer than the specified maximum.
An instable supply voltage may significantly decrease the radio performance
and stability.
2.2 Absolute maximum ratings
Parameter Min. Max. Unit
Supply voltage (VDD) -0.3 +3.9 V
Voltage on any digital pin (VDD<3.6V) -0.3 VDD+0.3 V
Voltage on any digital pin (VDD≥3.6V) -0.3 3.9 V
Input RF level 10 dBm
Flash endurance 10 000 Write/erase cycles
Table 3: Absolute maximum ratings
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2.3 Power consumption
2.3.1 Static
Parameter Power Test conditions Value Unit
TX Current
consumption
Maximum out
put power
Transmitter only, 1Mbps Bluetooth®LE,
CPU current not included, from nRF52
data sheet
8 mA
Full module current consumption
(Proteus-e module, Bluetooth®LE
firmware)
9.3 mA
Table 4: Current consumption - transmitting
Parameter Test conditions Value Unit
RX Current
consumption
Receiver only, 1Mbps Bluetooth®LE, CPU current not
included, from nRF52 data sheet 6.1 mA
Full module current consumption (Proteus-e module,
Bluetooth®LE firmware) 6.8 mA
Table 5: Current consumption - receiving
Parameter Test conditions Value Unit
Current
consumption Sleep (system off mode) 0.3 µA
Table 6: Current consumption - low power
Figure 3: Sleep current (no RAM retention, wake on reset) over operating temperature range
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2.4 Radio characteristics
Parameter Min. Max. Unit
Frequency 2360 2500 MHz
Table 7: Frequency range
Parameter Min. Max. Unit
RSSI accuracy valid range (±2dB) -90 -20 dBm
Table 8: RSSI accuracy
Parameter Value Unit
Enable TX or RX delay 140 µs
Enable TX or RX delay (fast mode) 40 µs
Disable TX delay 6 µs
Disable RX delay 0 µs
Table 9: Timing
Parameter Test conditions Value Unit
Output power Conducted +4 dBm
Radiated -4 dBm
Input sensitivity Conducted, BER=1E-3, 1Mbps, Bluetooth®LE -93 dBm
Conducted, BER=1E-3, 1Mbps, Bluetooth®LE, LDO mode -97 dBm
Radiated, BER=1E-3, 1Mbps, Bluetooth®LE -85 dBm
Table 10: Transmit and receive power
All transmit and receive power levels are measured on the evaluation board. The values
already include losses of transitions from module to motherboard to SMA or modules PCB
antenna. They are realistic values for the end application.
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