H High IP3 MMIC LNA at 1.8-2.4 GHz Application note for the BGA2012 The BGA2012 is a MMIC 50 Ω LNA block for cellular applications at 1.8 GHz to 2.4 GHz that require low noise, high gain and good linearity. Possible applications: • 1.8 GHz - DECT - gain 15 dB, low noise 1.7 dB, supply curent 4 mA • 1.9 GHz - CDMA - high IIP3 +10 dBm, gain 12 dB, NF 2.2 dB, supply current 7 mA • 2.4 GHz - Blue Tooth - gain 11.5 dB, NF 2.3 dB, supply current 6 mA The MMIC is produced in the single metal DPO Philips process and is packaged in the small 6 pins SOT363. The circuit is equipped with a control pin that can set the amplifier to low currentlow noise mode or to high current-high linearity mode and/or disable (off) mode. A simple solution requires only input/output decoupling capacitors. This report describes an application in which the LNA can be tuned for gain and input IP3. At 1900 Mhz, the input IP3 is adjustable between 5 dBm at 16 dB gain and 10 dBm at 12 dB gain. Circuit description The LNA is a one stage amplifier. The RF transistor is biased with the controlled bias circuit that can set the collector current of RF transistor to the desired value. With the control voltage from 0 to 3 Volt it is posssible to set the collector current from 0 to 7 mA (enable/disable H function as well). The best performance on gain, noise and linearity is achieved in the range of 4 to 7 mA. Low noise and high gain is obtained by the current source that biases the RF transistor and by the layout of RF transistor. The device works directly without the external components except input/output decoupling capacitors. However, to get even higher gain and linearity (IIP3), a few more external components are necessary. The next four examples show some possible applications: • • • • version 1 : simple solution with only 2 decoupling capacitors; acceptable gain and low noise version 2: high gain through output shunt coil ⇒ one component more than version 1 version 3: high IIP3 and high gain with input filter ⇒ three components more than version1 version 4: super high IIP3 ⇒ like version 3 with ustripline to ground Measured results General conditions: Vsupply= 3V, temp=25 deg Quick overview of all four versions: frequency=1.9 GHz Parameter 2 Unit Gain |S21| dB NF dB IIP3 dBm Version1 Version 2 Version 3 Version 4 simple high gain high IIP3, gain high IIP3 13.7 14.0 1.7 1.7 -9 -7 14.9 15.5 1.8 1.8 -9 -7 15.4 15.8 2.0 2.1 0 5 12.0 12.3 2.1 2.3 7 10 Conditions Isupply [mA] 4 7 4 7 4 7 note: IIP3 - input IP3 measured with ∆f=100 kHz and Pin -25 dBm Isupply - is a total supply current from 3 Volt supply source Control current from a control voltage does not exceed 120 uA. (@max Vc=3V) The next tabels and figures show more data for each version. 2 H Version 1 Parameter Unit 0Gain |S21| 2 dB NF 1.8 GHz 13.6 14.3 14.4 1.7 1.7 1.7 dB Return Loss dB input 10 Return Loss dB output 9 IIP3 dBm ∆f=100kHz Frequency 1.9 GHz 2.1 GHz 13.2 12.5 13.9 13.1 14 13.2 1.7 1.8 1.7 1.8 1.7 1.8 9 11 11 11 8 9 9 9 -9 -7 -7 2.4 GHz 11.5 12.1 12.2 2.3 2.3 2.3 12 10 Conditions Isupply [mA] Vcontrol [V] 2.0 3.5 5.3 2.6 7 3.0 2.0 3.5 5.3 2.6 7 3.0 3.5 2.0 2.6 5.3 7 3.0 2.0 3.5 2.6 5.3 7 3.0 3.5 2.0 5.3 2.6 7 3.0 Application diagram Vc Vs Vc Vs Bias Circuit RFoutput Out RFinput In C2 C1 SOT363 BGA2012 gnd notes: 1. There are 4 types of demo board layouts available: no stripline (marked L0), 0.5 mm, 1.0 mm and 1.5 mm stripline. The L0 PCB should be used for application version 1. 2. The metal under pin 5 and 6 is filled with vias to the ground plane to reduce inductance. 3. The standard demo board also needs three 0 Ù SMD’s (0603) at the spots marked with an X. Additional components to adjust the biasing can be placed at these spots. C1 C2 x x x C4 C3 <-------20mm-------> Demo board Component C1 C2 C3 C4 Component C1, C2 C3, C4 Value 100 pF 100 pF 22 nF 22 nF Typ Philips 0603 Philips 0603 Philips 0603 Philips 0603 Function DC decoupling capacitors LF filter of dc supply source <-------20mm-------> 3 H Version 2 Parameter Gain |S21| 2 Unit dB NF dB 1.8 GHz 14.8 15.6 16.0 1.7 1.7 1.8 Return Loss dB input 10 Return Loss dB output 9 IIP3 dBm ∆f=100kHz Frequency 1.9 GHz 2.1 GHz 14.5 13.0 15.2 13.8 15.5 14.0 1.7 1.8 1.7 1.9 1.8 1.9 8 10 10 11 9 9 10 10 -9 -7 -7 Conditions Isupply [mA] Vcontrol [V] 1.8 3.5 5.3 2.5 7.5 3.0 1.8 3.5 5.3 2.5 7.5 3.0 3.5 1.8 2.5 5.3 7.5 3.0 1.8 3.5 2.5 5.3 7.5 3.0 3.5 1.8 5.3 2.5 7.5 3.0 2.4 GHz 11.0 11.4 11.5 2.2 2.3 2.3 12 10 Application diagram Vc C3 Vc Vs L1 Vs Bias Circuit Out RFinput RFoutput In C2 C1 SOT363 BGA2012 gnd notes: 1. There are 4 types of demo board layouts available: no stripline (marked L0), 0.5 mm, 1.0 mm and 1.5 mm stripline. The L0 PCB should be used for application version 2. 2. The metal under pin 5 and 6 is filled with vias to the ground plane to reduce inductance. 3. The standard demo board also needs three 0 Ù SMD’s (0603) at the spots marked with an X. Additional components to adjust the biasing can be placed at these spots. C1 C2 x L1 x x C4 C3 <-------20mm-------> Demo board Component C1 C2 C3 C4 L1 Component C1, C2 C3, C4 L1 Value 100 pF 100 pF 22 nF 22 nF 10 nH Typ Philips 0603 Philips 0603 Philips 0603 Philips 0603 TDK 0603 Function DC decoupling capacitors LF filter of dc supply source Output schunt coil, higher Vce <-------20mm-------> 4 H Version 3 Parameter Gain |S21| 2 Unit dB NF dB 1.8 GHz 15.3 16.1 16.2 2.0 2.0 2.1 Return Loss dB input 23 Return Loss dB output 10 IIP3 dBm ∆f=100kHz Frequency 1.9 GHz 2.1 GHz 15.0 13.5 15.7 14.0 15.8 14.1 2.0 2.1 2.1 2.3 2.2 2.3 18 22 23 18 9 10 10 12 -1 3 5 Conditions Isupply [mA] Vcontrol [V] 1.8 3.5 5.3 2.5 7.5 3.0 1.8 3.5 5.3 2.5 7.5 3.0 3.5 1.8 2.5 5.3 7.5 3.0 1.8 3.5 2.5 5.3 7.5 3.0 3.5 1.8 5.3 2.5 7.5 3.0 2.4 GHz 10.9 11.4 11.4 2.4 2.5 2.6 14 13 Application diagram Vc C5 C3 Vc C4 Vs L1 Vs Bias Circuit L2 Out RFinput RFoutput In C2 C1 SOT363 BGA2012 gnd notes: 1. There are 4 types of demo board layouts available: no stripline (marked L0), 0.5 mm, 1.0 mm and 1.5 mm stripline. The L0 PCB should be used for application version 3. 2. The metal under pin 5 and 6 is filled with vias to the ground plane to reduce inductance. 3. The standard demo board also needs three 0 Ù SMD’s (0603) at the spots marked with an X. Additional components to adjust the biasing can be placed at these spots. C4 L2 C1 C2 x L1 x x C5 C3 <-------20mm-------> <-------20mm-------> Demo board Component C1 C2 C3 C4 C5 L1 L2 Component C1, C2 C3, C5 L1 L2, C4 Value 100 pF 100 pF 22 nF 100 nF 22 nH 3.9 nH 3.9 nH Typ Philips 0603 Philips 0603 Philips 0603 Philips 0805 Philips 0603 TDK 0603 TDK0603 Function DC decoupling capacitors LF filter of dc supply source Output schunt coil, higher Vce Input LP filter to increase IP3 5 H Version 4 with 0.5 mm stripline Parameter Gain |S21| 2 Unit dB NF dB 1.8 GHz 14.0 14.4 14.5 2.0 2.2 2.2 Return Loss dB input 11 Return Loss dB output 8 IIP3 dBm ∆f=100kHz Frequency Conditions 1.9 GHz 2.1 GHz 2.4 GHz Isupply [mA] Vcontrol [V] 1.8 13.3 12.5 9.9 3.5 5.3 2.5 13.9 12.9 10.3 7.5 3.0 14.0 13.0 10.3 1.8 2.1 2.2 2.5 3.5 5.3 2.5 2.2 2.3 2.7 7.5 3.0 2.3 2.4 2.7 13 3.5 1.8 14 2.5 5.3 14 16 16 7.5 3.0 1.8 8 3.5 2.5 8 5.3 7.5 3.0 8 8 10 1 3.5 1.8 6 5.3 2.5 7* 7.5 3.0 * with 1.5 mm stripline, the IIP3 improves to 10 dBm at 12.2 dB gain Application diagram Vc C5 C3 C4 L1 Vs Vc Vs Bias Circuit L2 Out RFinput RFoutput In C2 C1 SOT363 BGA2012 gnd u-strip 0.5~1.5 mm, see note notes: 1. There are 4 types of demo board layouts available: no stripline, 0.5 mm, 1.0 mm and 1.5 mm stripline; marked L0, L05, L10, L15. 2. The u-stripline to ground is optimized for each length. For no stripline, the metal under pin 5 and 6 is filled with vias to the ground plane to reduce inductance. For the stripline versions, the stripline ends in 2 vias. 3. The standard demo board also needs three 0 Ù SMD’s (0603) at the spots marked with an X. Additional components to adjust the biasing can be placed at these spots. C4 L2 C1 u-stripline C2 x L1 x x C5 C3 <-------20mm-------> Demo board Component C1 C2 C3 C4 C5 L1 L2 Value 100 pF 100 pF 22 nF 100 nF 22 nH 3.9 nH 3.9 nH Component Function like in version 3 Typ Philips 0603 Philips 0603 Philips 0603 Philips 0805 Philips 0603 TDK 0603 TDK0603 <-------20mm-------> 6