Product Specs

Table Of Contents
53 Reference circuitry
Page
551
L3
15nH
C9
1.0µF
L2
10µH
VDD_nRF
Optional
DEC1
C10
C2
12pF
C4
100nF
C8
4.7µF
X1
12pF
32MHz
C1
C11
X2
32.768kHz
12pF
12pF
C7
DEC1
P0.00/XL1
P0.01/XL2
P0.02/AIN0
P0.03/AIN1
P0.04/AIN2
P0.05/AIN3
P0.06
P0.07
P0.08
P0.09
P0.10
N.C.
VSS
VSS
XC2
XC1
DEC3
DEC2
VSS_PA
ANT
P0.24
P0.23
P0.22
SWDIO
SWDCLK
A1
XC2
B2
XC1
C2
DEC3
A2
DEC2
D2
D1
E1
P0.24
E2
P0.23
F2
P0.22
G1
SWDIO
F1
SWDCLK
100pF
C6
100pF
L1
RF
3.3nH
C3
nRF52832
1.0pF
Note:
The value of C_tune1 and C_tune2 must be
tuned to match the selected NFC antenna.
VDD_nRF
U1
nRF52832-CIAA
C5
100nF
53.6 Schematic CIAA WLCSP with DC/DC regulator and NFC setup
B7
P0.00/XL1 D7
P0.01/XL2 C7
P0.02/AIN0C6
P0.03/AIN1D6
P0.04/AIN2E6
P0.06
F7
P0.07
F6
NFC1
Ctune1
TBD
P0.08
G7
G6
NFC2
Ctune2
G5
C3
E3
TBD
F5
Figure 174: CIAA WLCSP with DC/DC regulator and NFC setup
For PCB reference layouts, see Reference layout nRF52 Series.
Table 149: Bill of material for CIAA WLCSP with DC/DC converter and NFC setup
Designator
Value
Description
Footprint
C1, C2, C10, C11
12 pF Capacitor, NP0, ±2%
0201
C3
1.0 pF Capacitor, NP0, ±5%
0201
C4, C5
100 nF Capacitor, X7R, ±10%
0201
C6, C7
100 pF Capacitor, NP0, ±5%
0201
C8
4.7 µF Capacitor, X5R, ±10%
0603
C9
1.0 µF Capacitor, X5R, ±5%
0402
C
tune1
, C
tune2
TBD pF Capacitor, NP0, ±5%
0201
L1
3.3 nH High frequency chip inductor ±5%
0201
L2
10 µH Chip inductor, IDC,min = 50 mA, ±20%
0603
L3
15 nH High frequency chip inductor ±10%
0402
U1
nRF52832-CIAA Multi-protocol Bluetooth low energy, ANT, and 2.4 GHz proprietary system on chip
WLCSP_C50
X1
32 MHz XTAL SMD 2016, 32 MHz, Cl=8 pF, Total Tol: ±40 ppm
XTAL_2016
X2
32.768 kHz XTAL SMD 2012, 32.768 kHz, CI=9 pF, ±50 ppm
XTAL_2012
53.7 PCB guidelines
A well-designed PCB is necessary to achieve good RF performance. A poor layout can lead to loss in
performance or functionality.
A qualified RF layout for the IC and its surrounding components, including matching networks, can be
downloaded from Reference layout nRF52 Series.
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 the reference circuits are designed for use with a 50 ohm single end
antenna.
A PCB with a minimum of two layers, including a ground plane, is recommended for optimal performance.
On PCBs with more than two layers, put a keep-out area on the inner layers directly below the antenna
H7
F4
H6
G4
H5
H4
H3
G3
H2
F3
G2
H1
A7
B6
A6
DEC4
C5
C4
VDD
P0.11
P0.12
P0.13
P0.14
P0.15
P0.16
P0.17
P0.18
P0.19
P0.20
P0.21/RESET
VDD
DCC
DEC4
VSS
VSS
P0.31/AIN7
P0.30/AIN6
P0.29/AIN5
P0.28/AIN4
P0.27
P0.26
P0.25
P0.11
P0.12
P0.13
P0.14
P0.15
P0.16
P0.17
P0.18
P0.19
P0.20
P0.21
B5
A5
A4
A3
B4
D3
B3
P0.31/AIN7
P0.30/AIN6
P0.29/AIN5
P0.28/AIN4
P0.27
P0.26
P0.25