Texas Instruments WL1835MODCOM8B User manual

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WL1835MODCOM8B WLAN MIMO and Bluetooth®Module EVM
User's Guide
SWRU359E–September 2013–Revised September 2015
WL1835MODCOM8B WLAN MIMO and Bluetooth®Module
EVM
This user's guide describes how to use the TI WL1835MODCOM8B board to evaluate the performance of
the TI WL18MODGB module.
Contents
1 Warning ....................................................................................................................... 2
2 Introduction ................................................................................................................... 3
2.1 Features.............................................................................................................. 4
2.2 Applications.......................................................................................................... 5
2.3 TI Module Key Benefits ............................................................................................ 5
3 Board Pin Assignment ...................................................................................................... 6
3.1 Pin Descriptions..................................................................................................... 7
4 Electrical Characteristics.................................................................................................... 9
5 Approved Antenna Types and Maximum Gain Values ................................................................. 9
6 On-Board Antenna Configuration ........................................................................................ 10
6.1 VSWR............................................................................................................... 10
6.2 Efficiency ........................................................................................................... 11
6.3 Radio Pattern ...................................................................................................... 11
6.4 ANT1................................................................................................................ 12
6.5 ANT2................................................................................................................ 13
7 Circuit Design............................................................................................................... 15
7.1 Schematic .......................................................................................................... 15
7.2 Bill of Materials (BOM)............................................................................................ 16
8 Layout Guidelines .......................................................................................................... 17
8.1 Board Layout....................................................................................................... 17
List of Figures
1 WL1835MODCOM8B Top View ........................................................................................... 3
2 Board Top View.............................................................................................................. 6
3 Board Bottom View.......................................................................................................... 6
4 Antenna VSWR............................................................................................................. 10
5 Antenna Efficiency ......................................................................................................... 11
6 Radio Pattern ............................................................................................................... 11
7 ANT1 Polarization.......................................................................................................... 12
8 ANT1 Polarization.......................................................................................................... 12
9 ANT1 Polarization.......................................................................................................... 13
10 ANT2 Polarization.......................................................................................................... 13
11 ANT2 Polarization.......................................................................................................... 14
12 ANT2 Polarization.......................................................................................................... 14
13 Schematic ................................................................................................................... 15
14 Layer 1....................................................................................................................... 17
15 Layer 2....................................................................................................................... 17
16 Layer 3....................................................................................................................... 18

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17 Layer 4....................................................................................................................... 18
18 Module Layout Guidelines (Top Layer).................................................................................. 19
19 Module Layout Guidelines (Bottom Layer).............................................................................. 19
20 Trace Design for the PCB Layout........................................................................................ 20
21 Layer 1 Combined With Layer 2 ......................................................................................... 20
22 Top Layer – Antenna and RF Trace Routing Layout Guidelines .................................................... 21
23 Bottom Layer – Antenna and RF Trace Routing Layout Guidelines ................................................ 21
24 MIMO Antenna Spacing................................................................................................... 22
List of Tables
1 Approved Antenna Types and Maximum Gain Values ................................................................. 9
2 BOM.......................................................................................................................... 16
3 Module Layout Guidelines ................................................................................................ 18
4 Antenna and RF Trace Routing Layout Guidelines.................................................................... 20
Trademarks
WiLink8 is a trademark of Texas Instruments.
Bluetooth is a registered trademark of Bluetooth SIG, Inc.
Android is a trademark of Google Inc.
Linux is a registered trademark of Linux Foundation.
Wi-Fi is a registered trademark of Wi-Fi Alliance.
1 Warning
The WL1835MODCOM8B board is tested to comply with ETSI/R&TTE over temperatures from –20°C to
85°C.
This board should not be modified to operate in other frequency bands other than what they are designed
for.
FCC Licensing Requirements for the Wi-Fi and Bluetooth Radio Module of the EVM:
For evaluation only; not FCC approved for resale. This kit is designed to allow:
1. Product developers to evaluate electronic components, circuitry, or software associated with the kit to
determine whether to incorporate such items in a finished product
2. Software developers to write software applications for use with the end product. This kit is not a
finished product and when assembled may not be resold or otherwise marketed unless all required
FCC equipment authorizations are first obtained. Operation is subject to the condition that this product
not cause harmful interference to licensed radio stations and that this product accept harmful
interference. Unless the assembled kit is designed to operate under part 15, part 18, or part 95 of this
chapter, the operator of the kit must operate under the authority of an FCC license holder or must
secure an experimental authorization under part 5 of this chapter.
Per TI’s Regulatory Compliance Information located in the WL1835ModCOMB8B User’s Guide’s
“Evaluation Board/Kit/Module (EVM) Additional Terms,” this EVM cannot be used for production purposes
and is explicitly restricted from end-product introduction.
Use of this EVM requires the developer to provide a minimum distance of at least 20 cm from the antenna
to all persons in order to minimize risk of potential radiation hazards.
CAUTION
Do not leave the EVM powered when unattended.

FCC/IC Regulatory Compliance
FCC Part 15 Class A Compliant
IC ICES-003 Class A Compliant
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2 Introduction
The WL1835MODCOM8B device is a Wi-Fi®MIMO, Bluetooth, and Bluetooth Low Energy (BLE) module
board with the TI WL18MODGB module. WL18MODGB is built-in TI WL1835 IEEE 802.11 b/g/n and
Bluetooth 4.0 solutions to provide the best Wi-Fi and Bluetooth coexistence interoperability and power-
saving technologies from TI.
Figure 1. WL1835MODCOM8B Top View

IC ID: 451I-WL1835COM
This device complies with Industry
Canada licence-exempt RSS
standard(s). Operation is subject to the
following two conditions: (1) this device
may not cause interference, and (2) this
device must accept any interference,
including that may cause undesired
operation of the device.
FCC ID: Z64-WL1835COM
This device complies with part 15 of the
FCC Rules. Operation is subject to the
following two conditions: (1) This device
may not cause harmful interference, and
(2) this device must accept any
interference received, including
interference that may cause undesired
operation.
Introduction www.ti.com
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(continued)
2.1 Features
• WLAN, Bluetooth, BLE on a module board
• 100-pin board card
• Dimension 76.0 mm(L) x 31.0 mm(W)
• WLAN 2.4 GHz SISO (20- and 40-MHz channels), 2.4-GHz MIMO (20-MHz channels)
• Support for BLE dual mode
• Seamless integration with TI Sitara and other application processors
• Design for TI AM335X general-purpose EVM
• WLAN and Bluetooth, BLE cores are software and hardware compatible with prior WL127x, WL128x
and CC256x offerings, for smooth migration to device.
• Shared HCI transport for Bluetooth and BLE over UART and SDIO for WLAN.
• Wi-Fi / Bluetooth single antenna co-existence
• Built-in chip antenna
• Optional U.FL RF connector for external 2.4-GHz band antenna
• Direct connection to battery using external switching mode power supply supporting 4.8-V to 2.9-V
operation
• VIO in the 1.8-V domain

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2.2 Applications
• Internet of Things Multimedia
• Home Electronics
• Home Appliances and White Goods
• Industrial and Home Automation
• Smart Gateway and Metering
• Video Conferencing
• Video Camera and Security
2.3 TI Module Key Benefits
• Reduces Design Overhead: Single WiLink8™ Module Scales Across Wi-Fi and Bluetooth.
• WLAN High Throughput: 80 Mbps (TCP), 100 Mbps (UDP)
•Bluetooth 4.0 + BLE (Smart Ready)
• Wi-Fi-Bluetooth Single Antenna Coexistence
• Low Power (30–50% Less than Previous Generation)
• Available as Easy-to-Use FCC, ETSI, and Telec Certified Module
• Lower Manufacturing Costs, Saving Board Space and Minimizing RF Expertise
• AM335x Linux®and Android™ Reference Platform Accelerates Customer Development and Time to
Market

U1
WL18MODGB
Board Pin Assignment www.ti.com
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3 Board Pin Assignment
Figure 2. Board Top View
Figure 3. Board Bottom View

www.ti.com Board Pin Assignment
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3.1 Pin Descriptions
No. Name Type Description
1 SLOW_CLK I Slow clock input
2 GND G Ground
3 GND G Ground
4 WL_EN I WLAN Enable
5 VBAT P Power supply input
6 GND G Ground
7 VBAT P Power supply input
8 VIO P Power supply input for I/O pin
9 GND G Ground
10 N.C. No connection
11 WL_RS232_TX O WLAN tool RS232 output
12 N.C. No connection
13 WL_RS232_RX I WLAN tool RS232 input
14 N.C. No connection
15 WL_UART_DBG O WLAN Logger output
16 N.C. No connection
17 N.C. No connection
18 GND G Ground
19 GND G Ground
20 SDIO_CLK I WLAN SDIO clock
21 N.C. No connection
22 GND G Ground
23 N.C. No connection
24 SDIO_CMD I/O WLAN SDIO command
25 N.C. No connection
26 SDIO_D0 I/O WLAN SDIO data bit 0
27 N.C. No connection
28 SDIO_D1 I/O WLAN SDIO data bit 1
29 N.C. No connection
30 SDIO_D2 I/O WLAN SDIO data bit 2
31 N.C. No connection
32 SDIO_D3 I/O WLAN SDIO data bit 3
33 N.C. No connection
34 WLAN_IRQ O WLAN SDIO interrupt out
35 N.C. No connection
36 N.C. No connection
37 GND G Ground
38 N.C. No connection
39 N.C. No connection
40 N.C. No connection
41 N.C. No connection
42 GND G Ground
43 N.C. No connection
44 N.C. No connection
45 N.C. No connection
46 N.C. No connection
47 GND G Ground

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No. Name Type Description
48 N.C. No connection
49 N.C. No connection
50 N.C. No connection
51 N.C. No connection
52 PCM_IF_CLK I/O Bluetooth PCM clock input or output
53 N.C. No connection
54 PCM_IF_FSYNC I/O Bluetooth PCM frame sync input or output
55 N.C. No connection
56 PCM_IF_DIN I Bluetooth PCM data input
57 N.C. No connection
58 PCM_IF_DOUT O Bluetooth PCM data output
59 N.C. No connection
60 GND G Ground
61 N.C. No connection
62 N.C. No connection
63 GND G Ground
64 GND G Ground
65 N.C. No connection
66 BT_UART_IF_TX O Bluetooth HCI UART transmit output
67 N.C. No connection
68 BT_UART_IF_RX I Bluetooth HCI UART receive input
69 N.C. No connection
70 BT_UART_IF_CTS I Bluetooth HCI UART Clear to Send input
71 N.C. No connection
72 BT_UART_IF_RTS O Bluetooth HCI UART Request to Send output
73 N.C. No connection
74 BT_FUNC1 O BT_HOST_WAKE_UP Signal to wake up the host from Bluetooth
75 N.C. No connection
76 BT_UART_DEBUG O Bluetooth Logger UART output
77 GND G Ground
78 GPIO9 I/O General-purpose I/O
79 N.C. No connection
80 N.C. No connection
81 N.C. No connection
82 N.C. No connection
83 GND G Ground
84 N.C. No connection
85 N.C. No connection
86 N.C. No connection
87 GND G Ground
88 N.C. No connection
89 BT_EN I Bluetooth Enable
90 N.C. No connection
91 N.C. No connection
92 GND G Ground
93 BT_FUNC2 I BT_WAKE_UP Bluetooth wakeup from host
94 N.C. No connection
95 GND G Ground
96 GPIO11 I/O General-purpose I/O

www.ti.com Electrical Characteristics
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No. Name Type Description
97 GND G Ground
98 GPIO12 I/O General-purpose I/O
99 N.C. General-purpose I/O
100 GPIO10 I/O General-purpose I/O
4 Electrical Characteristics
Refer to the detailed data in the WL18MODGB data sheet (SWRS152) for electrical characteristics.
5 Approved Antenna Types and Maximum Gain Values
This device is intended only for OEM integrators under the following conditions:
• Install the antenna so that 20 cm is maintained between the antenna and user.
• Do not co-locate the transmitter module with any other transmitter or antenna.
• Operate the radio transmitter using only an antenna of a type and maximum (or lesser) gain approved
by TI. Table 1 lists the antennas approved by TI for use with the radio transmitter along with maximum
allowable gain values. Antenna types not included in the list or having a gain greater than the
maximum indicated are strictly prohibited for use with this transmitter
Table 1. Approved Antenna Types and Maximum Gain Values
Antenna Type Brand 2.4–2.5 GHz Unit
PCB Ethertronics –0.600
dBi
Dipole LSR 2.00
PCB Laird 2.00
Chip Pulse 3.20
PIFA LSR 2.00
Chip TDK 2.4
NOTE: If these conditions cannot be met (for example, with certain laptop configurations or co-
location with another transmitter), the FCC/IC authorization will not be considered valid and
the FCC ID/IC ID cannot be used on the final product. In these circumstances, the OEM
integrator is responsible for reevaluating the end product (including the transmitter) and
obtaining a separate FCC/IC authorization.

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6 On-Board Antenna Configuration
6.1 VSWR
Figure 4 shows the antenna VSWR.
Figure 4. Antenna VSWR

www.ti.com On-Board Antenna Configuration
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6.2 Efficiency
Figure 5 shows the antenna efficiency.
Figure 5. Antenna Efficiency
6.3 Radio Pattern
Figure 6 shows the radio pattern of the WL1835MODCOM8B device.
Figure 6. Radio Pattern

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6.4 ANT1
Figure 7 shows the ANT1 polarization of the WL1835MODCOM8B device.
Figure 7. ANT1 Polarization
Figure 8. ANT1 Polarization

www.ti.com On-Board Antenna Configuration
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Figure 9. ANT1 Polarization
6.5 ANT2
Figure 10 shows the ANT2 polarization of the WL1835MODCOM8B device.
Figure 10. ANT2 Polarization

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Figure 11. ANT2 Polarization
Figure 12. ANT2 Polarization

EDGE CONNECTOR - MALE
WL_BG ANT2WL_BG/BT ANT1
Short PIN Header (1-2)
for entering test mode.
Open for function mode.
These two TPs for test mode
when WL_IRQ pull high.
WL_UART_DBG
BT_AUD_CLK
BT_AUD_FSYNC
BT_AUD_IN
WL_RS232_TX
WL_RS232_RX
BT_HCI_TX
BT_HCI_RX
BT_HCI_CTS
BT_HCI_RTS
BT_EN_SOC
BT_UART_DBG
SDIO_CLK_WL
SDIO_CMD_WL
SDIO_D0_WL
SDIO_D2_WL
SDIO_D3_WL
SDIO_D1_WL
WLAN_EN_SOC
BT_AUD_OUT
BT_FUNC1
GPIO9
GPIO11
GPIO12
GPIO10
SLOW_CLK
BT_FUNC2
WLAN_IRQ
2G4_ANT1_WB
2G4_ANT2_W
SDIO_D3_WL
GPIO12
SDIO_D2_WL
GPIO11
SDIO_D0_WL
SDIO_D1_WL
GPIO9
WLAN_IRQ
GPIO10
2G4_ANT2_W
WL_RS232_TX
WL_RS232_RX
2G4_ANT1_WB
BT_FUNC1
BT_FUNC2
BT_HCI_RX
BT_HCI_TX
BT_HCI_CTS
BT_HCI_RTS
BT_AUD_IN
BT_AUD_OUT
BT_AUD_CLK
BT_AUD_FSYNC
SDIO_CMD_WL
SDIO_CLK_WL
SLOW_CLK
WL_UART_DBG
BT_UART_DBG
BT_EN_SOC
WLAN_EN_SOC
VBAT_IN
VIO_IN
VIO_IN
VBAT_IN
VIO_IN
VIO_IN
R20 10k
0402
R25 0R 0402
C5
10pF
0402
J6
U.FL-R-SMT(10)
U.FL
1
2
3
C14
4pF
0402
ANT2
ANT016008LCD2442MA1
ANT-N3-1.6X0.8MM-B
5G
B2
FEED
A
2.4G
B1
R17 0R 0402
C6
10pF
0402
J2
NU_100pin Micro Edge MEC6
SD-100P
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
TP4
1
C7
NU_10pF
0402 C9
2pF
0402
R12 0R 0402
C11
1.2pF
0402
R11 0R 0402
ANT1
ANT016008LCD2442MA1
ANT-N3-1.6X0.8MM-A
5G
B2
FEED
A
2.4G
B1
C1
1uF
0402
R30 0R 0402
R9 0R 0402
J5
U.FL-R-SMT(10)
U.FL
1
2
3
C10
NU_0.3pF
0402
R10 0R
0402
TP1
1
TP5
1
R2 0R 0402
0RR21 0402
TP6
1
0RR19 0402
OSC1
1V8 / 32.768kHz
OSC-3.2X2.5
EN 1
VCC 4
OUT
3
GND
2
R6
0R
0402
R3 0R 0402
R16 0R 0402
U1
WL1835MODGB
E-13.4X13.3-N100_0.75-TOP
GPIO9
3
GPIO12
5
GPIO11
2
GPIO10
4
GND 17
VIO 38
VBAT 47
EXT_32K 36
BT_AUD_FSYNC
58
BT_AUD_IN
56
BT_AUD_OUT
57
BT_AUD_CLK
60
WL_SDIO_D2
12
WL_SDIO_CLK
8
WL_SDIO_D3
13
WL_SDIO_D0
10
WL_SDIO_D1
11
WL_SDIO_CMD
6
BT_HCI_RTS
50
BT_HCI_RX
53
BT_HCI_TX
52
BT_HCI_CTS
51
GND
16
GPIO_4 25
GPIO_2 26
GPIO_1 27
BT_EN_SOC 41
WLAN_IRQ
14
WLAN_EN_SOC 40
BT_UART_DBG 43
WL_UART_DBG 42
GND G13
GND G14
GND G15
GND G16
GND G9
GND G10
GND 48
GND G11
GND G12
VBAT 46
GND 28
GND G1
GND G2
GND G3
GND G4
GND G5
GND G6
GND G7
GND G8
2G4_ANT1_WB 32
GND
64
GND
1
GND 20
RESERVED1 21
RESERVED2 22
GND 37
GND 19 RESERVED3
62
GND G17
GND G18
GND
G19
GND
G20
GND
G21
GND
G22
GND
G23
GND
G24
GND
G25
GND
G26
GND
G27
GND
G28
GND
G29
GND
G30
GND
G31
GND
G32
GND
G33
GND
G34
GND
G35
GND 23
GND
59
GND 34
GND 29
GND
7
2G4_ANT2_W 18
GND
49
GND
9
GND 31
GND 35
GND
15
GND
55
GND 45 GND 44
GND 30
GND 24
GND
63
GND
61
GND 39 GND 33
GND
54
GND
G36
C2
10uF
0603
R31
0R
0402
J1
HEADER 1x2
H-1X2_2MM
1 2
R1 0R 0402
R29 0R 0402
R8 0R 0402
L1
0402
1.1nH
TP3
1
R28 0R 0402
0RR24 0402
R7 0R 0402
TP8
1
R14 0R 0402
C8
NU_10pF
0402
C4
0.1uF
0402
R27 0R 0402
R13 0R 0402
R15 0R 0402
C3
0.1uF
0402
0RR22 0402
R18 0R 0402
R4 0R 0402
R23 0R 0402
R32
0R
0402
C13
8pF
0402
R5 NU_0R
0402
C12
NU
0402
J3
HEADER 1x2
H-1X2_2MM
1 2
J4
HEADER 1x2
H-1X2_2MM
1 2
0RR26 0402
L2
1.5nH
0402
TP2
1
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7 Circuit Design
7.1 Schematic
Figure 13. Schematic

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7.2 Bill of Materials (BOM)
Table 2 lists the bill of materials.
Table 2. BOM
1 TI WL1835 Wi-Fi/Bluetooth Module WL18MODGB U1
2 XOSC 3225 / 32.768 kHz / 1.8 V / ±50 ppm 7XZ3200005 OSC1
3 ANT / Chip / 2.4 GHz, 5 GHz / Peak Gain >5 dBi ANT016008LCD2442MA1 ANT1, ANT2
4 CON Male 1x2 / Pitch P301-SGP-040/028-02 J1, J3, J4
5 DC JUMPER / PITCH 2.0 mm CMJ-20BB J1, J3
6 Mini RF Header Receptacle U.FL-R-SMT-1(10) J5, J6
7 IND 0402 / 1.1 nH / ±0.05 nH / SMD LQP15MN1N1W02 L1
8 IND 0402 / 1.5 nH / ±0.05 nH / SMD LQP15MN1N5W02 L2
9 CAP 0402 / 1.2 pF / 50 V / C0G / ±0.1 pF GJM1555C1H1R2BB01 C11
10 CAP 0402 / 2.2 pF / 50 V / C0G / ±0.1 pF GJM1555C1H2R2BB01 C9
11 CAP 0402 / 4 pF / 50 V / C0G / ±0.1 pF GJM1555C1H4R0BB01 C14
12 CAP 0402 / 8 pF / 50 V / C0G / ±0.1 pF GJM1555C1H8R0BB01 C13
13 CAP 0402 / 10 pF / 50 V / NPO / ±5% 0402N100J500LT C7, C8
14 CAP 0402 / 0.1 µF / 6.3 V / X7R / ±10% 0402B104K100CT C3, C4
15 CAP 0402 / 1 µF / 6.3 V / X5R / ±10% / HF GRM155R60J105KE19D C1
16 CAP 0603 / 10 µF / 6.3 V / X5R / ±20% C1608X5R0J106M C2
17 RES 0402 / 0R / ±5% WR04X000 PTL
R1, R2, R3, R4, R5, R6, R7, R8, R9,
R10, R11, R12, R13, R14, R15,
R16, R17, R18, R19, R21, R22,
R23, R24, R25, R26, R27, R28,
R29, R30, R31, R32
18 RES 0402 / 10K / ±5% WR04X103 JTL R20

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8 Layout Guidelines
8.1 Board Layout
Figure 14 shows the WL1835MODCOM8B 4-layer board. Table 3,Figure 15,Figure 16,Figure 17,
Figure 18, and Figure 19 show instances of good layout practices.
Figure 14. Layer 1
Figure 15. Layer 2

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Figure 16. Layer 3
Figure 17. Layer 4
Table 3. Module Layout Guidelines
Reference Guideline Description
1 The proximity of ground vias must be close to the pad.
2 Signal traces must not be run underneath the module on the layer where the module is mounted.
3 Have a complete ground pour in layer 2 for thermal dissipation.
4 Have a solid ground plane and ground vias under the module for stable system and thermal dissipation.
5Increase the ground pour in the first layer and have all of the traces from the first layer on the inner layers, if
possible.
6Signal traces can be run on a third layer under the solid ground layer, which is below the module mounting
layer.

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WL1835MODCOM8B WLAN MIMO and Bluetooth®Module EVM
Figure 18. Module Layout Guidelines (Top Layer)
Figure 19. Module Layout Guidelines (Bottom Layer)
Figure 20 shows the trace design for the PCB. A 50-Ωimpedance match on the trace to the antenna
should be used. Also, 50-Ωtraces are recommended for the PCB layout.

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WL1835MODCOM8B WLAN MIMO and Bluetooth®Module EVM
Figure 20. Trace Design for the PCB Layout
Figure 21 shows layer 1 with the trace to the antenna over ground layer 2.
Figure 21. Layer 1 Combined With Layer 2
Table 4,Figure 22, and Figure 23 describe instances of good layout practices for the antenna and RF
trace routing.
Table 4. Antenna and RF Trace Routing Layout Guidelines
Reference Guideline Description
1The RF trace antenna feed must be as short as possible beyond the ground reference. At this point, the trace
starts to radiate.
2The RF trace bends must be gradual with an approximate maximum bend of 45 degrees with trace mitered. RF
traces must not have sharp corners.
3 RF traces must have via stitching on the ground plane beside the RF trace on both sides
4 RF traces must have constant impedance (microstrip transmission line).
5For best results, the RF trace ground layer must be the ground layer immediately below the RF trace. The
ground layer must be solid.
6 There must be no traces or ground under the antenna section.
7RF traces must be as short as possible. The antenna, RF traces, and modules must be on the edge of the PCB
product. The proximity of the antenna to the enclosure and the enclosure material must also be considered.