FM Radio Amplifier with Filter Using the 2SC5347A Application Note Overview This application note explains about ON Semiconductor’s 2SC5347A which is used as a Low Noise Amplifier (LNA) for FM Radio. http://onsemi.com The 2SC5347A is a silicon bipolar transistor best suited for high-frequency applications which is assembled in the 3-pin surface mount package of the high collector dissipation. For information about the performance, please refer to the datasheet of this product. Since the evaluation board is adjusted to achieve optimal performance in worldwide FM band, the product can provide 22.5dB gain and 1.6dB noise figure. A standard material FR4 is used for the printed circuit board (PCB). Please note that the losses of the PCB and the SMA connector are not excluded from the noise figure. © Semiconductor Components Industries, LLC, 2014 September 2014- Rev. 0 1 Publication Order Number: AND2SC5347A_1/D FM Radio Amplifier with Filter Using the 2SC5347A ■Summary of Data Ta = 25ºC, Input Power = -40 dBm, Zo = 75 Ω Parameter Symbol DC Voltage DC Current Power Gain Noise Figure *Zo = 50 Ω Input Return Loss Output Return Loss Isolation Condition Result Unit Vcc 5 V Icc 12.6 mA Gp NF RLin RLout ISL f = 76 MHz 22.7 f = 90 MHz 23.0 f = 108 MHz 22.5 f = 76 MHz 2.05 f = 90 MHz 1.7 f = 108 MHz 1.6 f = 76 MHz 21.5 f = 90 MHz 18.3 f = 108 MHz 12.5 f = 76 MHz 12.6 f = 90 MHz 13.3 f = 108 MHz 15.1 f = 76 MHz 29.5 f = 90 MHz 27.8 f = 108 MHz 26.5 dB dB dB dB dB Gain 1dB Compression Input Power Pin1dB f = 100 MHz -17 dBm Input 3rd order Intercept Point IIP3 f1 = 100 MHz f2 = 101 MHz Pin = -35dBm -8 dBm *Noise Figure includes the loss of PCB and SMA connector. http://www.onsemi.com 2 FM Radio Amplifier with Filter Using the 2SC5347A ■Circuit Design Vcc = 5V R1 C6 INPUT L1 C1 C8 R2 C7 L5 C3 R3 C2 TR1 R5 C4 L2 R4 L3 C5 ■Evaluation Board http://www.onsemi.com 3 L4 OUTPUT R6 FM Radio Amplifier with Filter Using the 2SC5347A ■Bill of Materials Item Symbol Value Manufacture Size Bip-Tr TR1 2SC5347A ON Semiconductor SC-62 C1 22 pF Murata GRM155 1005 C2 82 pF Murata GRM155 1005 C3 22 pF Murata GRM155 1005 C4 2 pF Murata GRM155 1005 C5 1000 pF Murata GRM155 1005 C6 10 pF Murata GRM155 1005 C7 0.1 uF ROHM MCH182CN 1608 C8 0.1 uF ROHM MCH182CN 1608 R1 39 kΩ Various 1608 R2 39 Ω Various 1005 R3 2.2 kΩ Various 1005 R4 100 Ω Various 1005 R5 100 kΩ Various 1005 R6 100 kΩ Various 1005 L1 100 nH TDK MLG1005S 1005 L2 82 nH TOKO LL1005-FH 1005 L3 120 nH TOKO LL1608-FS 1608 L4 39 nH TDK MLG1005S 1005 L5 150 nH TOKO LL1608-FS 1608 Capacitor Resistor Inductor Material FR-4 http://www.onsemi.com 4 25 x 16 mm FM Radio Amplifier with Filter Using the 2SC5347A 30 ‐20 25 ‐25 20 ‐30 Isolation ‐ dB Power Gain ‐ dB ■Measurement Results 15 10 ‐35 ‐40 ‐45 5 ‐50 0 0 50 100 Frequency ‐ MHz 150 0 200 50 150 200 Figure 2 Isolation vs. Frequency 5 ‐5 0 Output Return Loss ‐ dB 0 ‐10 ‐15 ‐20 ‐25 ‐30 ‐5 ‐10 ‐15 ‐20 ‐25 ‐30 ‐35 ‐35 50 100 150 Frequency ‐ MHz Figure 3 Input Return Loss vs. Frequency 90 MHz 200 0 50 100 150 200 Frequency ‐ MHz Figure 4 Output Return Loss vs. Frequency S(4,4) 0 S(3,3) Input Return Loss ‐ dB Figure 1 Power Gain vs. Frequency 100 Frequency ‐ MHz 90 MHz 70 (70.00MHz MHz to to110 MHz freq 110.0MHz) freq 110.0MHz) 70(70.00MHz MHz toto110 MHz Figure 5 Smith Chart S11 Figure 6 Smith Chart S22 http://www.onsemi.com 5 FM Radio Amplifier with Filter Using the 2SC5347A ■Measurement Results Zo = 50 Ω 40 4 S21 20 S11,S21,S12,S22 ‐ dB 3.5 Noise Figure ‐ dB 3 2.5 2 1.5 1 0 ‐20 S11→ ←S22 ‐40 S12 ‐60 ‐80 0.5 0 60 70 80 90 100 Frequency ‐ MHz 110 120 ‐100 0.1 Figure 7 Noise Figure vs. Frequency 1 10 Frequency ‐ MHz 100 Figure 8 Wide Span Pin = -35 dBm 15 Output Power ‐ dBm 10 5 0 ‐5 ‐10 ‐15 ‐20 ‐40 ‐35 ‐30 ‐25 ‐20 Input Power ‐ dBm Figure 9 Output Power vs. Input Power ‐15 ‐10 Figure 10 Input 3rd order Intercept Point http://www.onsemi.com 6 1000 FM Radio Amplifier with Filter Using the 2SC5347A APPLICATIONS INFORMATION Gain 1dB Compression Input Power (Pin1dB) Pin1dB is measured the input power level when the power gain increase more 1 dB than that of linear range. Input 3rd order Intercept Point (IIP3) IIP3 is defined by the following equations. IIP3 = Pin + (IM3 / 2) (eq. 1) ON Semiconductor and the ON logo are registered trademarks of Semiconductor Components Industries, LLC (SCILLC) or its subsidiaries in the United States and/or other countries. SCILLC owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of SCILLC’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf . SCILLC reserves the right to make changes without further notice to any products herein. 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