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help me create the antenna for the nrf52840

jakobabs

@copilot help me create the antenna for the nrf52840

copilot

The nRF52840 is a versatile SoC from Nordic Semiconductor that includes a built-in RF transceiver supporting various wireless protocols. In designing the antenna for the nRF52840, you need to follow careful layout and design principles to ensure optimal RF performance.

Key Steps to Design the Antenna for the nRF52840:

Select the Antenna Type: The most common types for this frequency are PCB trace antennas like meandered or inverted-F antennas (IFA), chip antennas, or external antennas.
Place the Antenna Properly: Position the antenna at the edge of the PCB, away from noisy components.
Impedance Matching: Ensure the antenna is impedance-matched to 50 Ω to maximize power transfer and minimize reflection.
RF Layout Guidelines: Follow Nordic’s PCB layout guidelines for the RF section, such as grounding, shielding, and trace width.

Steps for a Meandered Inverted-F Antenna (MIFA)

Antenna Layout:
- Create a meandered line on the PCB with a length that achieves resonance at approximately 2.4 GHz.
- Start with a trace width of around 1 mm and a length adjusted to fit the space available.
Ground Plane:
- Ensure there is a continuous ground plane under the RF section, but keep it away from the antenna area itself.
Matching Network:
- Include a matching network with SMT components like capacitors and inductors to fine-tune the impedance. Use the network connected to the antenna feedpoint.
Testing and Tuning:
- Use a vector network analyzer to measure the impedance and adjust the matching network as necessary.

Sample Schematic Connections:

Connect the antenna to the nRF52840 as follows:

Antenna Feedpoint: Connect to $U1:ANT$ .
Matching Network: This typically includes components like an inductor (L1) and two capacitors (C16 and C17).

Example connections:

Connect $U1:ANT$ to matching network components.
Connect matching network output to the antenna feedpoint.

Example Layout:

Antenna Design:
- Start from the $U1:ANT$ pin and draw the antenna trace.
Ground Plane Clearance:
- Keep a clearance of around 2-3 mm around the antenna’s trace.

Adding Parts to Your Schematic:

You can use the built-in components in Flux:

Matching Network Components: Choose appropriate 0402 or 0603 capacitors and inductors.
PCB Antenna: Design the trace to match your antenna specifications directly on the PCB layout tool in Flux.

Example Values for a Matching Network:

$L1$ : 3.9 nH
$C16$ : 0.5 pF
$C17$ : 1.0 pF

Would you like to proceed with a specific antenna type, or do you need further details on the matching network components and layout? Let me know, and I can provide more tailored guidance!

Someone is typing...

Note: IC2 the PAT9130 trackball sensor from PixArt. Since the datasheet is confi...

jakobabs

Note: IC2 the PAT9130 trackball sensor from PixArt. Since the datasheet is confidential, the information shown here is in compliance with the NDA I signed. No further information regarding the PAT9130 will be given.

Someone is typing...

C5 -> W1 C6 -> AD23 C7 -> A22 C8 -> AD14 C9 -> B1

jakobabs

C5 -> W1 C6 -> AD23 C7 -> A22 C8 -> AD14 C9 -> B1

Someone is typing...

what capacitance should I use for this oscillator?

jakobabs

@copilot what capacitance should I use for this oscillator?

copilot

To determine the appropriate capacitance values for your oscillator circuit with the ABS07-32.768KHZ-T crystal, you typically need to refer to the crystal's datasheet. The common load capacitance for 32.768 kHz crystals is usually between 9 pF to 12.5 pF.

However, based on common practices, you might start with 12 pF for the capacitors ($C13$ and $C12$) if the specific datasheet is not available.

Here is a typical configuration to connect your oscillator:

Connections:

Connect $X1$:P1 to $U1$:XL1/P0.00.
Connect $X1$:P2 to $U1$:XL2/P0.01.
Connect $X1$:P1 to $C13$:P2.
Connect $X1$:P2 to $C12$:P2.
Connect $C13$:P1 to GND.
Connect $C12$:P1 to GND.

This should give you a stable 32.768 kHz oscillation for your NRF52840-QIAA-R microcontroller. If you have the specific datasheet for your crystal, I would recommend confirming the exact load capacitance values.

Someone is typing...

TFT_TC

TFT_CC

TFT_RT

GPIO5

TFT_BL

TFT_SI

GPIO5

PAT_5

TFT_TC

TFT_RT

TFT_SO

GPIO3

TFT_CC

GPIO2

PAT_9

TFT_SO

PAT_8

GPIO2

TFT_SI

TFT_CK

GPIO1

TFT_DC

TFT_BL

GPIO6

GPIO3

3V3

PAT_7

GPIO4

TFT_CK

GPIO1

GPIO6

3V3

PAT_10

TFT_DC

Resistance

3.3kΩ

C15

Capacitance

12pF

Reviews

Generic Inductor
A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
jharwinbarrozo
16.2k
Generic Capacitor
A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF, 10pF, 100pF, 1000pF, 0.01uF, 0.1uF, 1.0uF, 10uF, 100uF, 1000uF, 10000uF 1.1pF, 11pF, 110pF, 1100pF 1.2pF, 12pF, 120pF, 1200pF 1.3pF, 13pF, 130pF, 1300pF 1.5pF, 15pF, 150pF, 1500pF, 0.015uF, 0.15uF, 1.5uF, 15uF, 150uF, 1500uF 1.6pF, 16pF, 160pF, 1600pF 1.8pF, 18pF, 180pF, 1800pF 2.0pF, 20pF, 200pF, 2000pF 2.2pF, 22pF, 220pF, 2200pF, 0.022uF, 0.22uF, 2.2uF, 22uF, 220uF, 2200uF 2.4pF, 24pF, 240pF, 2400pF 2.7pF, 27pF, 270pF, 2700pF 3.0pF, 30pF, 300pF, 3000pF 3.3pF, 33pF, 330pF, 3300pF, 0.033uF, 0.33uF, 3.3uF, 33uF, 330uF, 3300uF 3.6pF, 36pF, 360pF, 3600pF 3.9pF, 39pF, 390pF, 3900pF 4.3pF, 43pF, 430pF, 4300pF 4.7pF, 47pF, 470pF, 4700pF, 0.047uF, 0.47uF, 4.7uF, 47uF, 470uF, 4700uF 5.1pF, 51pF, 510pF, 5100pF 5.6pF, 56pF, 560pF, 5600pF 6.2pF, 62pF, 620pF, 6200pF 6.8pF, 68pF, 680pF, 6800pF, 0.068uF, 0.68uF, 6.8uF, 68uF, 680uF, 6800uF 7.5pF, 75pF, 750pF, 7500pF 8.2pF, 82pF, 820pF, 8200pF 9.1pF, 91pF, 910pF, 9100pF #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Generic Resistor
A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Ground
A common return path for electric current. Commonly known as ground.
jharwinbarrozo
20.5M
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
Net Portal
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
jharwinbarrozo
43.0M
RMCF0805JT47K0
General Purpose Thick Film Standard Power and High-Power Chip Resistor 47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film Features: - RMCF – standard power ratings - RMCP – high power ratings - Nickel barrier terminations standard - Power derating from 100% at 70ºC to zero at +155ºC - RoHS compliant, REACH compliant, and halogen free - AEC-Q200 compliant
jharwinbarrozo
1.2M
875105359001
10 µF 16 V Aluminum - Polymer Capacitors Radial, Can - SMD 30mOhm 2000 Hrs @ 105°C #commonpartslibrary #capacitor #aluminumpolymer #radialcan
jharwinbarrozo
1.2M
CTL1206FYW1T
Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric)
jharwinbarrozo
1.1M
1070TR
Battery Holder (Open) Coin, 20.0mm 1 Cell SMD (SMT) Tab bate or batt #forLedBlink
jharwinbarrozo
700.5k

Project Name

Design Challenge - Jacob Kelly

Description

NRF52840 evaluation board with a battery charger (BQ24072), display(Adafruit 1.47" 172x320 ST7789), and a trackball sensor (PAT9130)

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor	Qty 1
Arrow	$6.65–$30.84
Digi-Key	$7.63–$33.66
LCSC	$10.33–$29.31
Mouser	$6.30–$135.63
Verical	$7.17–$15.32

Controls

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