TRC103 915 MHz Transceiver Reference Design Introduction This application note presents a PCB reference design for RFM’s TRC103 transceiver IC operating in the 902 to 928 MHz band. The reference design includes an integrated PCB antenna. The reference design schematic is shown in Figure 1 below. • • • • Figure 1 - TRC103 915 MHz Reference Design Schematic Note the dot (band) orientation of L1 with respect to L2, and the orientation of L4 with respect to L5. www.RFM.com ©2010 by RF Monolithics, Inc. Technical support +1.800.704.6079 E-mail: [email protected] Page 1 of 7 AN0903 - 06/21/10 Bill of Materials The TRC103 915 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 www.RFM.com ©2010 by RF Monolithics, Inc. RFM TRC103 Transceiver IC RFM RF2040E Low-loss SAW Filter RFM XTL1020 Crystal, 12.80000 MHz 5.6 nH ±5%, 0603 RF inductor 5.6 nH ±5%, 0603 RF inductor RF Bead, 300 ohm, Fair Rite 2506033017Y0, 0603 8.2 nH ±5%, 0603 RF inductor 8.2 nH ±5%, 0603 RF inductor 100 nH ±5%, 0603 RF inductor 18 nH ±5%, 0603 RF inductor zero ohm resistor, 0603 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 100 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 not used 3.3 ± 0.25 pF, 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/trc103_pcb.zip Technical support +1.800.704.6079 E-mail: [email protected] Page 2 of 7 AN0903 - 06/21/10 Circuit Board Layers • • • • Figure 2 - Top Assembly Figure 2 shows the TRC103 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 TRC103. PADs PCB design files and Gerber files of the reference design layout are available at www.rfm.com/products/apnotes/trc103_pcb.zip. Figure 3 - Top Silkscreen The top silkscreen is shown in Figure 3. www.RFM.com ©2010 by RF Monolithics, Inc. Technical support +1.800.704.6079 E-mail: [email protected] Page 3 of 7 AN0903 - 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. www.RFM.com ©2010 by RF Monolithics, Inc. Technical support +1.800.704.6079 E-mail: [email protected] Page 4 of 7 AN0903 - 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. www.RFM.com ©2010 by RF Monolithics, Inc. Technical support +1.800.704.6079 E-mail: [email protected] Page 5 of 7 AN0903 - 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] Page 6 of 7 AN0903 - 06/21/10 Figure 10 shows the assembled TRC103 915 MHz reference design PCB. Figure 10 - Assembled Reference Design PCB Reference Design Range Testing The TRC103 915 MHz reference design achieves a typical range of 1200 feet (365 meters) in “open field” conditions 3.5 feet (1 meter) off the ground, using a data rate of 50 kb/s. www.RFM.com ©2010 by RF Monolithics, Inc. Technical support +1.800.704.6079 E-mail: [email protected] Page 7 of 7 AN0903 - 06/21/10