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Production Guidelines

The module is housed in a hybrid SMD package that supports hand and 
automated assembly techniques. Since the modules contain discrete 
components internally, the assembly procedures are critical to ensuring 
the reliable function of the modules. The following procedures should be 
reviewed with and practiced by all assembly personnel.

Hand Assembly

Pads located on the bottom 
of the module are the primary 
mounting surface (Figure 35). 
Since these pads are inaccessible 
during mounting, castellations 
that run up the side of the module 
have been provided to facilitate 
solder wicking to the module’s 
underside. This allows for very 
quick hand soldering for prototyping and small volume production.  If the 
recommended pad guidelines have been followed, the pads will protrude 
slightly past the edge of the module. Use a fine soldering tip to heat the 
board pad and the castellation, then introduce solder to the pad at the 
module’s edge. The solder will wick underneath the module, providing 
reliable attachment. Tack one module corner first and then work around the 
device, taking care not to exceed the times in  Figure 36.

Automated Assembly

For high-volume assembly, the modules are generally auto-placed. 
The modules have been designed to maintain compatibility with reflow 
processing techniques; however, due to their hybrid nature, certain aspects 
of the assembly process are far more critical than for other component 
types. Following are brief discussions of the three primary areas where 
caution must be observed.

Castellations

PCB Pads

Soldering Iron
Tip

Solder

Figure 35: Soldering Technique

Reflow Temperature Profile

The single most critical stage in the automated assembly process is the 
reflow stage. The reflow profile in Figure 37 should not be exceeded 
because excessive temperatures or transport times during reflow will 
irreparably damage the modules. Assembly personnel need to pay careful 
attention to the oven’s profile to ensure that it meets the requirements 
necessary to successfully reflow all components while still remaining 
within the limits mandated by the modules. The figure below shows the 
recommended reflow oven profile for the modules.

Shock During Reflow Transport

Since some internal module components may reflow along with the 
components placed on the board being assembled, it is imperative that 
the modules not be subjected to shock or vibration during the time solder 
is liquid. Should a shock be applied, some internal components could be 
lifted from their pads, causing the module to not function properly.

Washability

The modules are wash-resistant, but are not hermetically sealed. Linx 
recommends wash-free manufacturing; however, the modules can be 
subjected to a wash cycle provided that a drying time is allowed prior 
to applying electrical power to the modules. The drying time should be 
sufficient to allow any moisture that may have migrated into the module 
to evaporate, thus eliminating the potential for shorting damage during 
power-up or testing.  If the wash contains contaminants, the performance 
may be adversely affected, even after drying.

125°C

185°C

217°C

255°C

235°C

60

120

30

150

180

210

240

270

300

330

360

0

90

50

100

150

200

250

300

Recommended RoHS Profile

Max RoHS Profile

Recommended Non-RoHS Profile

180°C

Temperature 

(

o

C)

Time (Seconds)

Figure 37: Maximum Reflow Temperature Profile

Warning: 

Pay attention to the absolute maximum solder times.

Figure 36: Absolute Maximum Solder Times

Absolute Maximum Solder Times

Hand Solder Temperature: +427ºC for 10 seconds for lead-free alloys

Reflow Oven: +255ºC max (see Figure 37)

Summary of Contents for MDEV-868-NT

Page 1: ...NT Series Transceiver Module Data Guide...

Page 2: ...e to RF interference that can prevent communication RF products without frequency agility or hopping implemented are more subject to interference This module does not have frequency agility built in b...

Page 3: ...figuration also giving access to additional features The modules are capable of generating 12 5dBm into 50 ohms and have a typical sensitivity of 113dBm Housed in a compact reflow compatible SMD packa...

Page 4: ...4 300 kHz 4 11 Spurious Emissions 62 dBm Receiver Sensitivity Baud Band 1 111 113 dBm 5 11 Baud Band 2 108 110 dBm 5 11 Baud Band 3 104 106 dBm 5 11 Baud Band 4 100 102 dBm 5 11 Electrical Specificat...

Page 5: ...Notes RSSI Dynamic Range 60 dB Transmitter Section Output Power PO 15 5 12 5 dBm 6 Output Power Control Range 28 dB Harmonic Emissions PH 42 36 dBc 7 Frequency Deviation Baud Band 1 30 kHz 3 11 Baud...

Page 6: ...5 5 RX Icc mA Supply Voltage V 40 C 25 C 85 C 14 15 16 17 2 5 3 5 4 5 5 5 TX Icc mA Supply Voltage V 40 C 25 C 85 C Figure 5 NT Series Transceiver Output Power vs LVL_ADJ Resistance Figure 6 NT Serie...

Page 7: ...630 s 1 2 00V div 2 2 00V div 500 s div 1 2 T R_SEL READY 690 s Figure 11 NT Series Transceiver RSSI Voltage vs Input Power Figure 12 NT Series Transceiver Receiver Turn On Time from VCC Figure 13 NT...

Page 8: ...operation in the 863 870MHz and 902 928MHz frequency bands The RF synthesizer contains a VCO and a low noise fractional N PLL The VCO operates at two times the fundamental frequency to reduce spurious...

Page 9: ...gh or leave open for the high est power connect to GND through a resistor to lower the power 15 READY Ready This line is low when the transceiver is ready to communicate and high when it is busy This...

Page 10: ...ecture eliminates such considerations and allows virtually any signal including PWM Manchester and NRZ data to be sent at rates from 1kbps to 300kbps The Data Output Receive Mode is enabled when the T...

Page 11: ...ine so that they are lowered when POWER_DOWN is lowered Using the READY Output The Ready READY line can be used to monitor the status of the module It is logic high while the transceiver is busy and l...

Page 12: ...roller lines or hardwired The 868MHz channels are shown in Figure 25 and the 900MHz channels are shown in Figure 26 Baud Band Selection Baud Band BAUD1 BAUD0 Baud Rate kbps IF Bandwidth kHz Receiver S...

Page 13: ...1 for the full requirements 900MHz Channel Selection CHN_SEL2 CHN_SEL1 CHN_SEL0 CHANNEL FREQUENCY 0 0 0 3 903 37 0 0 1 15 906 37 0 1 0 21 907 87 0 1 1 27 909 37 1 0 0 39 912 37 1 0 1 51 915 37 1 1 0...

Page 14: ...C GND GND GND VCC GND GND GPIO GPIO GPIO GPIO GPIO GPIO GPIO GND GND 1 1 1 1 2 2 1 1 1 1 1 1 2 GND GND GND GND GND GND Figure 29 NT Series Transceiver Typical Application NT Series Transceiver 900MHz...

Page 15: ...onal details are in Application Note AN 00500 Figure 47 The transceiver includes a U FL connector as well as a line for the antenna connection This offers the designer a great deal of flexibility in a...

Page 16: ...better understanding its characteristics Interference may come from internal or external sources The first step is to eliminate interference from noise sources on the board This means paying careful a...

Page 17: ...ly under the module There should not be any copper or traces under the module on the same layer as the module just bare PCB The underside of the module has traces and vias that could short or couple t...

Page 18: ...mbly process is the reflow stage The reflow profile in Figure 37 should not be exceeded because excessive temperatures or transport times during reflow will irreparably damage the modules Assembly per...

Page 19: ...d configuration constraints In these instances a designer must make the best use of the area available to create as much ground OPTIMUM USABLE NOT RECOMMENDED NUT GROUND PLANE MAY BE NEEDED CASE Figur...

Page 20: ...ecialty Styles Linx offers a wide variety of specialized antenna styles Figure 43 Many of these styles utilize helical elements to reduce the overall antenna size while maintaining reasonable performa...

Page 21: ...testing laboratories across the country Many labs can also provide other certifications that the product may require at the same time such as UL CLASS A B etc Once the completed product has passed an...

Page 22: ...SEARCH RF OPTIONS CHOOSE LINX MODULE ORDER EVALUATION KIT S TEST MODULE S WITH BASIC HOOKUP INTERFACE TO CHOSEN CIRCUIT AND DEBUG CONSULT LINX REGARDING ANTENNA OPTIONS AND DESIGN LAY OUT BOARD SEND P...

Page 23: ...stomer including without limitation breach of contract breach of warranty strict liability or negligence Customer assumes all liability including without limitation liability for injury to person or p...

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