–

–

–

–

12

13

Using the Boards as a Design Reference

The master development boards included in this kit are very simple, yet

they illustrate some important techniques that should be incorporated

into the board layout. The module’s mounting pads extend slightly past

the edge of the part. This eases hand assembly and allows for better

heat conduction under the part if rework is necessary. A full ground plane

fill is placed on the bottom of the board. This ground plane serves three

important purposes:

First, since a quarter-wave antenna is employed, the ground plane is

critical to serve as a counterpoise (please see Application Note AN-00500

“Antennas: Design, Application, and Performance” for details on how a

ground plane affects antenna function).

Second, a ground plane will suppress the transfer of noise between stages

of a product, as well as unintentional radiation of noise into free space.

Third, a ground plane allows for the implementation of a microstrip feed

between the module and the antenna. The term microstrip refers to a PCB

trace running over a ground plane that is designed to serve as a 50-ohm

transmission line. See the ES Series data guide or the calculator available

on our website for details on microstrip calculations.

In Closing

Here at Linx, “Wireless Made Simple” is more than just our motto, it is our

commitment. A commitment to the highest caliber of product, service,

and support. That is why, should you have questions or encounter any

difficulties using the evaluation kit, you’ll be glad to know many resources

are available to assist you. First, check carefully for the obvious, then

visit our website at www.linxtechnologies.com or call +1 541 471 6256

between 8AM and 4PM Pacific Time to speak with an application engineer.

RX DATA

AUDIO

RSSI

RX PDN

RX RS232 SQ

RX DEC

AUDIO REF

1

2

3

4

5

6

7

8

9

TS2

CON9

GND

TX = NS

RX RS232 SQ

R26

10K

R25

10K

R23

10K

R24

2M

AUDIO REF

AUDIO

VCC

VCC

R19

39K

R20

2M

R18

10K

R21

39K

C2

0.01uF

VCC

GND

GND

GND

GND

RSSI

R22

390K

R17

5K

OUTA

1

INA-

2

INA+

3

GND

4

INB+

5

INB-

6

OUTB

7

VCC

8

U6

LMV393

R28

0

R27

0

TX = NS

VCC

GND

GND

GND

GND

TX RS232

RX RS232 SQ

GND

1

NC

2

NC

3

NC

4

VCC

5

NC

6

NC

7

GND

8

GND

9

DTR/PDN

10

RTS/TRSEL

11

TX DATA

12

RX DATA

13

NC

14

NC

15

GND

16

J3

HOST MODULE

PDN RS232

TX DATA

TX PDN

TX RS232

/CLK

TX ENC

/CLK SEL

GND

LO V DET

RX = NS

PDN RS232

PDN ENC

1

2

3

4

5

6

7

8

9

10

11

TS1

CON11

RX PDN

RSSI

RX DATA

AUDIO

AUDIO REF

VCC

GND

GND

ANT

1

GND

2

NC

3

GND

4

VCC

5

NC

6

NC

7

NC

8

NC

9

A REF

10

AUDIO

11

DATA

12

RSSI

13

PDN

14

NC

15

NC

16

U3

RXM-XXX-ES

TX = NS

TX PDN

TX DATA

LO V DET

/CLK SEL

/CLK

GND

GND

R14

220 ohm

VCC

PDN

1

LADJ

2

VCC

3

GND

4

DATA

5

/CLK

6

/CLK SEL

7

LO_V_D

8

GND

9

ANT

10

U2

TXM-XXX-ES

R29

22K

GND

RX = NS

GND

GND

ANT1

CONREVSMA001

RF SECTION

ENCODER/DECODER SECTION

Host Interface Header

Proto Signal Header

B1

9V BATTERY

GND

SW1

POWER SWITCH

GND

+ C1

220uF

GND

VCC

D11

DIODE400

J1

PWRJACK

GND

Vin

1

Vout

3

U1

LM7805 5V REGULATOR

POWER SUPPLY SECTION

HEADER SECTION

SQUELCH CIRCUIT

RS232 HOST INTERFACE BOARD

USB HOST INTERFACE BOARD

U1

C3

C4

C5

C1

J2

C2

3.3uF

3.3uF

3.3uF

MAX232

3.3uF

RS-232

4.7uF

C1+

V+

C1-

C2+

C2-

V-

T2OUT

R2IN

R2OUT

T2IN

T1IN

R1OUT

R1IN

T1OUT

GND

VCC

VCC

GND

GND

VCC

GND

GND

TX RS232

RX RS232

PDN

TR SEL

1

2

3

4

5

6

7

89

10

11

12

13

14

15

16

1

6

2

7

3

8

4

9

5

J1

HIB-DIPMODULE

GND

NC

NC

NC

VCC

NC

NC

GND

GND

DTR/PDN

RTS/TRSEL

TX DATA

RX DATA

NC

NC

GND

GND

GND

GND

GND

VCC

TX RS232

RX RS232

PDN

TR SEL

1

2

3

4

5

6

7

89

10

11

12

13

14

15

16

+

+

+

J1

HIB-DIPMODULE

GND

GND

GND

GND

GND

NC

NC

NC

VCC

NC

NC

GND

GND

DTR/PDN

RTS/TRSEL

TX DATA

RX DATA

NC

NC

GND

TX DATA

RX DATA

PDN

TRSEL

1

2

3

4

5

6

7

89

10

11

12

13

14

15

16

USBDP

USBDM

GND

DSR

DATA_IN

DATA_OUT

RTS

CTS

DTR

TX_IND

VCC

SUSP_IND

RX_IND

485_TX

RI

DCD

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

USB-B

GND

5V

DAT -

DAT+

GND

GND

GND

1

2

3

4

GND

SDM-USB-QS-S

J2

TX DATA

RX DATA

TRSEL

PDN

U1

USB Host Interface Board Schematic

Figure 10: USB Host Interface Board Schematic

RS232 Host Interface Board Schematic

RS232 HOST INTERFACE BOARD

USB HOST INTERFACE BOARD

U1

C3

C4

C5

C1

J2

C2

3.3uF

3.3uF

3.3uF

MAX232

3.3uF

RS-232

4.7uF

C1+

V+

C1-

C2+

C2-

V-

T2OUT

R2IN

R2OUT

T2IN

T1IN

R1OUT

R1IN

T1OUT

GND

VCC

VCC

GND

GND

VCC

GND

GND

TX RS232

RX RS232

PDN

TR SEL

1

2

3

4

5

6

7

89

10

11

12

13

14

15

16

1

6

2

7

3

8

4

9

5

J1

HIB-DIPMODULE

GND

NC

NC

NC

VCC

NC

NC

GND

GND

DTR/PDN

RTS/TRSEL

TX DATA

RX DATA

NC

NC

GND

GND

GND

GND

GND

VCC

TX RS232

RX RS232

PDN

TR SEL

1

2

3

4

5

6

7

89

10

11

12

13

14

15

16

+

+

+

J1

HIB-DIPMODULE

GND

GND

GND

GND

GND

NC

NC

NC

VCC

NC

NC

GND

GND

DTR/PDN

RTS/TRSEL

TX DATA

RX DATA

NC

NC

GND

TX DATA

RX DATA

PDN

TRSEL

1

2

3

4

5

6

7

89

10

11

12

13

14

15

16

USBDP

USBDM

GND

DSR

DATA_IN

DATA_OUT

RTS

CTS

DTR

TX_IND

VCC

SUSP_IND

RX_IND

485_TX

RI

DCD

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

USB-B

GND

5V

DAT -

DAT+

GND

GND

GND

1

2

3

4

GND

SDM-USB-QS-S

J2

TX DATA

RX DATA

TRSEL

PDN

U1

Figure 11: RS232 Host Interface Board Schematic

RF Section Schematic

Figure 12: RF Section Schematic

high engineering standards; however, it is the responsibility of the user to

ensure that the products are operated in a legal and appropriate manner.

The purchaser understands that legal operation may require additional

permits, approvals, or certifications prior to use, depending on the

country of operation.