AN0905

TRC105 403 MHz Transceiver Reference Design
Introduction
This application note presents a PCB reference design for RFM’s TRC105 transceiver IC operating in the
403 MHz band. The reference design includes an integrated PCB antenna. The reference design schematic is shown in Figure 1 below.
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Figure 1 - TRC105 403 MHz Reference Design Schematic
Note the dot (band) orientation of L1 with respect to L2, and the orientation of L4 with respect to L5.
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©2010 by RF Monolithics, Inc.
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Bill of Materials
The TRC105 403 MHz Reference Design BOM is presented below:
U1
U2
Y1
L1
L2
L3
L4
L5
L6
L7
L8
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
C13
R1
R2
PCB
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©2010 by RF Monolithics, Inc.
RFM TRC105 Transceiver IC
RFM RF3607D Low-loss SAW Filter
RFM XTL1020 Crystal, 12.80000 MHz
22 nH ±5%, 0603 RF inductor
22 nH ±5%, 0603 RF inductor
RF Bead, 300 ohm, Fair Rite 2506033017Y0, 0603
39 nH ±5%, 0603 RF inductor
39 nH ±5%, 0603 RF inductor
10 nH ±5%, 0603 RF inductor
5.6 nH ±5%, 0603 RF inductor
68 nH ±5%, 0603 RF inductor
1,000 pF ±5%, COG, 50 V, 0603 capacitor
0.0068 µF ±10%, X7R, 50 V, 0603 capacitor
0.1 µF ±10%, X5R, 50 V, 0603 capacitor
47 pF ±5%, COG, 50 V, 0603 capacitor
0.047 µF ±10%, X7R, 50 V, 0603 capacitor
470 pF ±5%, COG, 50 V, 0603 capacitor
not used
0.22 µF ±10%, X7R, 50 V, 0603 capacitor
1 µF ±10%, X5R, 50 V, 0603 capacitor
1 µF ±10%, X5R, 50 V, 0603 capacitor
10 µF ±10%, Tantalum, 16 V, B case capacitor
1.2 pF ±0.25 pF, COG, 50 V, 0603 capacitor
15 pF ±5%, COG, 50 V, 0603 capacitor
6.8K ±5%, 0.1 W, 0603 film resistor
1 ohm ±5%, 0.1 W, 0603 film resistor
see www.rfm.com/products/apnotes/trc105_pcb.zip
Technical support +1.800.704.6079
E-mail: [email protected]
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Circuit Board Layers
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Figure 2 - Top Assembly
Figure 2 shows the TRC105 reference design top assembly. Power supply and digital I/O signals are organized on the left, the printed antenna is on the right. Note the dot (band) orientation of L1 with respect
to L2, and the orientation of L4 with respect to L5. A wide variety of microcontrollers can be used to control the TRC105. PADs PCB design files and Gerber files of the reference design layout are available at
www.rfm.com/products/apnotes/trc105_pcb.zip.
Figure 3 - Top Silkscreen
The top silkscreen is shown in Figure 3.
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©2010 by RF Monolithics, Inc.
Technical support +1.800.704.6079
E-mail: [email protected]
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AN905 - 06/21/10
Figure 4 - Top Solder Mask
The top solder mask is shown in Figure 4.
Figure 5 - Top Etch
The top etch pattern is shown in Figure 5. Using ±5% COG RF capacitors where specified in the bill of
materials is important to reference design performance.
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©2010 by RF Monolithics, Inc.
Technical support +1.800.704.6079
E-mail: [email protected]
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AN905 - 06/21/10
Figure 6 - Drill & Layer Data
The drill and layer data is provided in Figure 6. The reference design is implemented on a two-sided
0.031 inch board with 1 ounce copper traces.
Figure 7 - Bottom Etch
Figure 7 shows the reference design bottom etch pattern.
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©2010 by RF Monolithics, Inc.
Technical support +1.800.704.6079
E-mail: [email protected]
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AN905 - 06/21/10
Figure 8 - Bottom Solder Mask
Figure 8 shows the reference design bottom solder mask.
Figure 9 - Bottom Silkscreen
Figure 9 shows the bottom silkscreen.
www.RFM.com
©2010 by RF Monolithics, Inc.
Technical support +1.800.704.6079
E-mail: [email protected]
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AN905 - 06/21/10
Figure 10 shows the assembled TRC105 403 MHz reference design PCB.
Figure 10 - Assembled Reference Design PCB
www.RFM.com
©2010 by RF Monolithics, Inc.
Technical support +1.800.704.6079
E-mail: [email protected]
Page 7 of 7
AN905 - 06/21/10