OM7690/BFU730F,598

AN11006 Single stage 2.3_2.7GHz LNA with BFU730F Rev. 4.0 — 21 June 2016 Application note Info Content Keywords BFU730F, LNA, 2.3-2.7 GHz, WiMAX, WLAN, ISM, LTE, High linearity. Abstract The document provides circuit, layout, BOM and performance information on 2.3-2.7 GHz LNA equipped with NXP’s BFU730F wide band transistor. This Application note is related to evaluation board OM7690/BFU730F,598 12nc 934065627598 AN11006 NXP Semiconductors 2.3_2.7GHz LNA Revision history Rev Date Description 1.0 20110106 Initial document 2.0 20110710 Schematic updated 3.0 20121120 Chapter added about switching time 4.0 20160621 Small updates Contact information For additional information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 2 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 1. Introduction The BFU730F is a discrete HBT that is produced using NXP Semiconductors’ advanced 110 GHz fT SiGe:C BiCmos process. SiGe:C is a normal silicon germanium process with the addition of Carbon in the base layer of the NPN transistor. The presence of carbon in the base layer suppresses the boron diffusion during wafer processing. This allows steeper and narrower SiGe HBT base and a heavier doped base. As a result, lower base resistance, lower noise and higher cut off frequency can be achieved. The BFU730F is one of a series of transistors made in SiGe:C. BFU710F, BFU760 and BFU790 are the other types, BFU710 is intended for ultra low current applications. The BFU760F and BFU790F are high current types and are intended for application where linearity is key. The BFU7XXF are ideal in all kind of applications where cost matters. It also gives design flexibility. 2. Requirements and design of the 2.3-2.7GHz LNA The BFU730 2.3-2.7GHz LNA EVB simplifies the evaluation of the BFU730 wideband transistor, for this frequency range, in which e.g. WLAN, Bluetooth, WiMax, LTE etc systems are present. The EVB enables testing of the device performance and requires no additional support circuitry. The board is fully assembled with BFU730, including input- and output matching, to optimize the performance. The input match is a compromise between best noise figure and good Input return loss. The board is supplied with two SMA connectors for input and output connection to RF test equipment. Table 1. Target spec. Target specification of the 2.3-2.7 GHz LNA. Vcc Icc NF Gain IRL ORL 3 10 18 >10 >10 V mA dB dB dB dB 3. Design The 2.3_2.7 GHz LNA consists of one stage grounded emitter BFU730F amplifier. For this amplifier 11 external components are used, for matching, biasing and decoupling. The design has been conducted using Agilent’s Advanced Design System (ADS). The 2D EM Momentum tool has been used to co-simulate the PCB. Results are given in paragraph 4.5. The LNA shows a gain of 20 dB, NF of 0.8 dB, input P1dB of –16.5 dBm and an input IP3 of 1.5 dBm The LNA shown in this application note is unconditional stable 10 MHz-20 GHz. AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 3 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 3.1 BFU730F 2.3-2.7 GHz LNA-ADS Simulation circuit Fig 1. ADS simulation circuit for 2.3-2.7 GHz LNA AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 4 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 3.2 BFU730F 2.3-2.7 GHz LNA - ADS Gain and match simulation results Fig 2. ADS Gain and match simulation results for 2.3-2.7 GHz LNA AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 5 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 3.3 BFU730F 2.3-2.7 GHz LNA - ADS NF simulation results Fig 3. ADS Noise Figure simulation results for 2.3-2.7 GHz LNA AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 6 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 3.4 BFU730F 2.3-2.7 GHz LNA - ADS Stability simulation results (1) As K≥1 and Mu≥1, the LNA is unconditionally stable for the whole frequency band Fig 4. ADS stability simulation results for 2.3-2.7 GHz LNA AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 7 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 4. Implementation 4.1 Schematic R2 R3 C4 GND Vcc GND R1 L3 C3 C5 L2 RF_INPUT BFU730F Fig 5. L1 C6 L4 C1 RF_OUTPUT R4 C7 BFU730F 2.3-2.7 GHz LNA schematic AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 8 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 4.2 Layout and assembly Fig 6. AN11006 Application note Layout and assembly information for BFU730F 2.3-2.7 GHz LNA EVB All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 9 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA Table 2. Bill of materials Designator Description Size Q1 2X2mm BFU730F PCB Value Type Note NXP Semiconductors HBT 20X35mm C1 Capacitor 0402 100 pF MurataGRM1555 DC block C3 Capacitor 0402 68 nF MurataGRM1555 Bias Decoupling C4 Capacitor 0402 6.8 pF MurataGRM1555 Bias Decoupling C5 Capacitor 0402 1 pF MurataGRM1555 Bias Decoupling C6 Capacitor 0402 3.3 pF MurataGRM1555 output match C7 Capacitor 0402 4.7 pF MurataGRM1555 output match L1 Inductor 0402 1.5 nH Murata LQW15 input match L2 Inductor 0402 8.7 nH Murata LQW15 input match L3 Inductor 0402 4.7 nH Murata LQW15 output match L4 Inductor 0402 3.6 nH Murata LQP15 output match R1 Resistor 0402 37 K Bias Setting R2 Resistor 0402 100 R Bias Setting Hfe and Temp spread cancellation R3 Resistor 0402 10 Ohm Stability R4 Resistor 0402 0R NA X1,X2 SMA RF connector - Johnson, End launch SMA 142-0701-841 RF input/ RF output X3 DC header - Molex, PCB header, Right Angle, 1 row, 3 way 901210763 Bias connector 4.3 PCB layout A good PCB Layout is an essential part of an RF circuit design. The EVB of the BFU730 can serve as a guideline for laying out a board using either the BFU730 or one of the other SiGe.C HBTs in the SOT343F package. Use controlled impedance lines for all high frequency inputs and outputs. Bypass VCC with decoupling capacitors, preferable located as close as possible to the device. For long bias lines it may be necessary to add decoupling capacitors along the line further away from the device. Proper grounding the emitters is also essential for the performance. Either connect the emitters directly to the AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 10 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA ground plane ore through vias, or do both. The material that has been used for the EVB is FR4 using the stack shown in Fig 7 (1) Material supplier is Isola Duraver; Er=4.6-4.9 Tδ=0.02 Fig 7. PCB material stack AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 11 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 4.4 LNA View Fig 8. 2.3_2.7 GHz LNA AN11006 Application note All information provided in this document is subject to legal disclaimers. Rev. 4.0 — 21 June 2016 © NXP B.V.2016. All rights reserved. 12 of 26 AN11006 NXP Semiconductors 2.3_2.7GHz LNA 4.5 Measurement results Table 3. Typical measurement results measured on the evaluation board. Temp=25 °C, frequency is 2.5GHz unless otherwise specified. Parameter Symbol Value Unit Supply Voltage Vcc 3 V Supply Current Icc 10 mA Noise Figure NF[1] 0.8 dB 21.2 dB 21 dB 20.5 dB 2.3 GHz Power Gain 2.5 GHz GP 2.7 GHz Input return Loss IRL 7.9 dB Output return Loss ORL 17.5 dB Input 1dB Gain compression Point Pi1dB -16.5 dBm Output 1dB Gain compression Point Po1dB +3.7 dBm Input third order intercept point IP3i +1.5 dBm Output third order intercept point IP3o +22.5 dBm Ton 430 us Toff 24 ns Remarks Power settling time [1] The NF and gain figures are being measured at the SMA connectors of the evaluation board, so losses of the connectors and the PCB of approximately 0.1 dB are not substracted 4.5.1 Faster Switching time