NRF52820-QDAA-R datasheet(426/437 Pages) NORDIC

426 / 437 page

Hardware and layout

Designator

Value

Description

Footprint

C1, C2, C15,

C16

12 pF

Capacitor, NP0, ±2%

0201

1.0 pF

Capacitor, NP0, ±5%

0201

1.2 pF

Capacitor, NP0, ±5%

0201

C5, C7, C11

100 nF

Capacitor, X7S, ±10%

0201

4.7 µF

Capacitor, X7R, ±10%

0603

820 pF

Capacitor, X7R, ±10%

0201

N.C.

Not mounted

0201

C10

100 pF

Capacitor, NP0, ±5%

0201

C12, C13

1.0 µF

Capacitor, X7S, ±10%

0402

4.7 nH

High frequency chip inductor, ±5%

0201

2.2 nH

High frequency chip inductor, ±5%

0201

nRF52820-

QDAA

Multiprotocol Bluetooth® Low Energy, IEEE

802.15.4, ANT, and 2.4 GHz proprietary System on

Chip

QFN-40

32 MHz

Crystal SMD 1612, 32 MHz, Cl=8 pF, Total Tol: ±40

ppm

XTAL_1612

32.768 kHz

Crystal SMD 2012, 32.768 kHz, Cl=9 pF, Total Tol:

±50 ppm

XTAL_2012

Table 125: Bill of material for circuit configuration no. 4

7.3.5 PCB guidelines

A well designed PCB is necessary to achieve good RF performance. Poor layout can lead to loss in

performance or functionality.

A qualified RF layout for the device and its surrounding components, including matching networks, can be

downloaded from www.nordicsemi.com.

To ensure optimal performance it is essential that you follow the schematics and layout references closely.

Especially in the case of the antenna matching circuitry (components between device pin ANT and the

antenna), any changes to the layout can change the behavior, resulting in degradation of RF performance

or a need to change component values. All reference circuits are designed for use with a 50 Ω single-

ended antenna.

A PCB with a minimum of four layers, including a ground plane, is recommended for optimal performance.

On the inner layers, put a keep-out area on the inner layers directly below the antenna matching circuitry

(components between device pin ANT and the antenna) to reduce the stray capacitances that influence RF

performance.

A matching network is needed between the RF pin ANT and the antenna, to match the antenna

impedance (normally 50 Ω) to the optimum RF load impedance for the chip. For optimum performance,

the impedance for the matching network should be set as described in the recommended package

reference circuitry in Reference circuitry on page 418.

The DC supply voltage should be decoupled as close as possible to the VDD pins with high performance RF

capacitors. See the schematics for recommended decoupling capacitor values. The supply voltage for the

chip should be filtered and routed separately from the supply voltages of any digital circuitry.

4463_156 v1.0

426

NRF52820-QDAA-R Datasheet(PDF) 426 Page - Nordic Semiconductor

NRF52820-QDAA-R Datasheet(HTML) 426 Page - Nordic Semiconductor

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL