MGA-231T6 High-Gain GPS LNA with Variable Current and Shutdown Function Data Sheet Description Features Avago Technologies' MGA-231T6 is a low-noise amplifier (LNA) designed for GPS/ISM/Wimax applications in the (0.9-3.5)GHz frequency range. The LNA uses Avago Technologies' proprietary GaAs Enhancement-mode pHEMT process to achieve high gain with very low noise figure and high linearity. Noise figure distribution is very tightly controlled. A CMOS-compatible shutdown pin is included either for turning the LNA on/off or for current adjustment. Very Low Noise Figure The low noise figure and high gain, coupled with low current consumption make it suitable for use in critical lowpower GPS applications or during low-battery situations. High Gain and Linearity Low External Component Count Low Shutdown Current CMOS compatible shutdown pin (SD) current @ Vsd= 1.8V : 0.11mA Useable down to 1.8V supply Adjustable current via single external resistor/voltage Small package dimension: 2.0(L)x1.3(W)x0.4(H) mm Specifications (Typical performance @ 25C) Component Image At 1.575GHz Surface Mount 2.0x1.3x0.4 mm3 6-lead UTSLP PIN 5: RFout Vdd = 2.85V, Vsd = 1.8V, Idd =4mA - Gain = 17.1 dB - NF = 1.06 dB - Input IP3 = 0.2 dBm - Input P1dB = -7.7 dBm PIN 4:NC [1] Application PIN 6: Vdd PIN 1: Vsd PIN 2: RFin 31YM PIN 3: NC LNA for GPS, WLAN and WIMAX Top View PIN 6: Vdd PIN 5: RFout PIN 1: Vsd GND PIN 4:NC [1] PIN 2: RFin PIN 3: NC Bottom View Note: 1. Pin 4 must be left unconnected 2. Package marking provides orientation and identification "31" = Product Code "Y" = Year of manufacture "M" = Month code of manufacture Absolute Maximum Rating[1] TA = 25C Symbol Parameter Units Absolute Max. Vdd Device Drain to Source Voltage[2] V 3.6 Idd Drain Current[2] mA 15 Pin,max CW RF Input Power (Vdd = 2.7V, Idd = 6mA) dBm 13 Pdiss Total Power Dissipation[4] mW 54 Tc[5] Recommended Operating Temperature[6] C -40 to +85 Tj Junction Temperature C 150 TSTG Storage Temperature C -65 to 150 Thermal Resistance [3] (Vdd = 2.85V, Vsd = 1.8V, Idd = 4mA), jc = 150.8C/W Notes: 1. Operation of this device in excess of any of these limits may cause permanent damage. 2. Assuming DC quiescent conditions. 3. Thermal resistance measured using Infra-Red measurement technique. 4. Board (module belly) temperature TB is 25C. Derate 6.63 mW/C for Tb > 141.86C 5. Tc is defined as case temperature, the temperature of the underside of the device where it makes contact with the circuit board 6. The device will function over the recommended range without degradation in reliability or permanent change in performance, but is not guaranteed to meet the electrical specification. 2 Electrical Specifications TA = 25C, DC bias for RF parameters is as specified below. Freq=1.575GHz - Typical Performance[1] Table 1a. Performance table under nominal operating conditions (Vdd =2.85V, Vsd = 1.8V, Idd = 4mA, R2 = 8.2 kOhm) Symbol Parameter and Test Condition Units Min. Typ Max. G Gain dB 15.2 17.1 18.7 NF[1] Noise Figure[1] dB - 1.06 1.41 IP1dB Input 1dB Compressed Power dBm - -7.7 - IIP3[3] Input 3rd Order Intercept Point (2-tone @ Fc +/- 2.5MHz) dBm - 0.2 - S11 Input Return Loss dB - -10 - S22 Output Return Loss dB - -10 - S12 Reverse Isolation dB - -29 - Idd Supply DC current at Shutdown (SD) voltage Vsd=2.7V mA - 4 6.6 Ish Shutdown Current @ VSD = 0V uA - 0.4 - Table 1b. Performance table under nominal operating conditions (Vdd =1.8V, Vsd = 2.6V, Idd = 3.5mA, R2 = 8.2 kOhm) Symbol Parameter and Test Condition Units Min. Typ Max. G Gain dB - 16.6 - NF[1] Noise Figure dB - 1.1 - IP1dB Input 1dB Compressed Power dBm - -7.5 - IIP3[3] Input 3rd Order Intercept Point (2-tone @ Fc +/- 2.5MHz) dBm - 0 - S11 Input Return Loss dB - -10 - S22 Output Return Loss dB - -10 - S12 Reverse Isolation dB - -28 - Idd Supply DC current at Shutdown (SD) voltage Vsd=2.7V mA - 3.5 - Ish Shutdown Current @ VSD = 0V uA - 0.2 - Table 1c. Performance table under nominal operating conditions (Vdd = Vsd = 2.7V, Idd = 6mA, R2 = 5.6 kOhm) Symbol Parameter and Test Condition Units Min. Typ Max. G Gain dB NF[1] Noise Figure dB - 17.9 1.0 - IP1dB Input 1dB Compressed Power dBm - -5.9 IIP3[3] Input 3rd Order Intercept Point (2-tone @ Fc +/- 2.5MHz) dBm - +2.7 - S11 Input Return Loss dB - -11 - S22 Output Return Loss dB - -11 - S12 Reverse Isolation dB - -29 - Idd Supply DC current at Shutdown (SD) voltage Vsd=2.7V mA - 6 Ish Shutdown Current @ VSD = 0V uA - 0.3 - - Notes: 1. NF is measured at DUT input leads with board loss deembedded. 2. Measurements at 1.575GHz obtained using demo board described in Figures 4. 3. 1.575GHz IIP3 test condition: FRF1 = 1572.5 MHz, FRF2 = 1577.5 MHz with input power of -20dBm per tone measured at the worst case side band. 3 Circuit Symbol Size Description L1 0201 22nH Inductor (Murata LQP03TN22NH00) L2 0201 2.6nH Inductor (Murata LQP03TN2N6B00) L3 0201 10nH Inductor (Murata LQP03TN10NH00) L4 0201 39nH Inductor (Murata LQP03TN39NJ00) C1 0201 0.1uF Capacitor (Murata GRM033R60J104K) C2 0201 47pF Capacitor (Murata GRM0335C1E470J) C3 0201 330pF Capacitor (Murata GRM033R71E331K) R1 0201 10ohm Resistor R2 0201 8.2Kohm Resistor (For biasing condition as stated in Table 1a/b) 5.6Kohm Resistor (For biasing condition as stated in Table 1c) Figure 1. Demo Board and application circuit components table 4 Vd Vsd R1 L1 (R1 and L1 optional, see notes [3] below) C1 C3 (C3 and R2 are optional, see notes [3, 4] below) C2 R2 (Rbias) MGA-231T6 L2 6 1 Bias/control RFin L3 L4 NU 2 5 3 4 RFout NU [1] Notes: 1. Pin 4 must be left unconnected 2. L3 and L4 form the input matching network. C2 and L2 form a matching network at the output of the LNA. 3. L1 and R1 isolates the demoboard from external disturbances during measurement. It is not needed in actual application. Likewise, C1 and C3 mitigate the effect of external noise pickup on the Vdd and SD lines respectively. These components are not required in actual operation. 4. Bias control is achieved by either varying the SD voltage with/without R2, or fixing the SD voltage to Vdd and adjusting R2 for the desired current. R2 = 8.2 kOhm will result in 4mA when Vdd = 2.85V, Vsd = 1.8V or Vdd = 1.8V, Vsd = 2.6V. R2 = 5.6 kOhm will result in 6mA when Vdd = Vsd = 2.7V. Figure 2. Demo board and application schematic diagram 5 10 9 8 7 6 5 4 3 2 1 0 8 6 5 2 1 0 5 10 15 20 25 Rbias (KOhm) 30 35 200 150 100 50 0 0.0 0.5 1.0 1.5 2.0 2.5 Vsd (V) 3.0 3.5 4.0 Figure 5. Isd vs Vsd vs Vdd 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 1.0 1.5 2.0 Vsd (V) 2.5 3.0 3.5 4.0 4 5 Idd (mA) 6 7 8 9 Vdd=1.8V Vdd=2.7V Vdd=2.85V Vdd=3.3 Vsd (V) Isd (uA) 10 9 8 7 6 5 4 3 2 1 0 Vdd=1.8V Vdd=2.7V Vdd=2.85V Vdd=3.3 250 0.5 Figure 4. Idd vs Vsd vs Vdd 350 300 0.0 40 Figure 3. Idd vs Rbias at Vdd= 2.85V, Vsd =1.8V Isd (mA) 4 3 0 1 2 3 1 2 3 Figure 6. Vsd vs Idd vs Vdd Vdd=1.8V Vdd=2.7V Vdd=2.85V Vdd=3.3 Figure 7. Isd vs Idd vs Vdd 6 Vdd=1.8V Vdd=2.7V Vdd=2.85V Vdd=3.3 7 Id (mA) Idd (mA) MGA-231T6 Typical Performance Curves at 25C, R2 = 8.2Kohm (unless specified otherwise) 4 5 Idd (mA) 6 7 8 9 MGA-231T6 Typical Performance Curves at 25C, R2 = 8.2Kohm, Vdd = 2.85V, Vsd = 1.8V (unless specified otherwise) 19 1.8 18 1.6 1.4 NF (dB) Gain (dB) 17 16 15 1.0 0.8 T=-40C T=25C T= 85C 14 1.2 T=-40C T=25C T= 85C 0.6 0.4 13 1 2 3 4 5 Id (mA) 6 7 8 1 9 Figure 8. Gain vs Idd vs Temp 2 3 4 5 Id (mA) 6 7 8 9 Figure 9. NF vs Idd vs Temp 0 4 -2 2 0 -6 IIP3 (dB) IP1dB (dB) -4 -8 -10 3mA 4mA 5mA 6mA 7mA -12 -14 -6 -8 1.6 1.8 2 2.2 2.4 2.6 Vdd (V) 2.8 3 3.2 3.4 IIP3 (dBm) Figure 10. IP1dB vs Vdd vs Idd 1 2 3 1.6 1.8 2 Figure 11. IIP3 vs Vdd vs Idd -40C 25C 85C Figure 12. IIP3 vs Id vs Temp 7 3mA 4mA 5mA 6mA 7mA -4 -16 5 4 3 2 1 0 -1 -2 -3 -4 -5 -2 4 5 Id (mA) 6 7 8 9 2.2 2.4 2.6 Vdd (V) 2.8 3 3.2 3.4 MGA-231T6 Typical Performance Curves at 25C, R2 = 8.2Kohm, Vdd = 2.85V, Vsd = 1.8V (unless specified otherwise) 0.0 Out of Band Gain Compression (dBm) Out of Band Gain Compression (dBm) 7.6 7.5 7.4 7.3 7.2 7.1 7 -40 -20 0 20 40 Temperature (C) 60 80 2.0 -1.5 -2.0 -2.5 -3.0 -40 -20 0 20 40 Temperature (C) 60 80 100 Figure 14. Input signal required at 1885MHz interference signal to cause 1dB gain compression at 1.575GHz vs Temp 2.0 Mu_n40C..Mu1 Mu_85C..Mu1 Mu_25C..Mu1 1.8 Mu_n30C..MuPrime1 Mu_85C..MuPrime1 Mu_25C..MuPrime1 1.8 1.6 1.6 1.4 1.4 1.2 1.2 1.0 1.0 0.8 0.8 0 2 4 6 8 10 12 freq, GHz 14 16 18 Figure 15. Edwards-Sinsky Output Stability Factor (Mu') vs Freq vs Temp 8 -1.0 -3.5 100 Figure 13. Input signal required at 890MHz interference signal to cause 1dB gain compression at 1.575GHz vs Temp -0.5 20 0 2 4 6 8 10 12 freq, GHz 14 16 18 Figure 16. Edwards-Sinsky Input Stability Factor (Mu') vs Freq vs Temp 20 MGA-231T6 Scattering Parameter Measurement Reference Planes Vdd (pin6) C2 L2 REFERENCE PLANE REFERENCE PLANE LNA RFin (pin2) RFout (pin5) Packaged LNA Vsd (pin1) Figure 17. Scattering parameter measurement reference planes 9 MGA-231T6 Scattering Parameter Measurement with Vdd = 2.85V, Idd = 4mA, L2 = 2.7nH, C2 = 47pF (Murata 0402) The S-parameters measurement reference planes are described in Figure 20. The PCB is 10mils Rogers R04350. Freq (GHz) S11 S11 S21 S21 S12 S12 S22 S212 Mag. Ang. Mag. Ang. Mag. Ang. Mag. Ang. 0.5 0.9798 -9.89 0.0963 -36.96 0.0001 72.50 0.9905 -22.07 0.6 0.9768 -11.15 0.1766 -42.68 0.0001 105.74 0.9896 -27.89 0.7 0.9721 -12.97 0.2867 -46.41 0.0001 -105.96 0.9824 -33.24 0.8 0.9610 -14.87 0.4312 -52.26 0.0005 -96.68 0.9865 -38.66 0.825 0.9610 -15.29 0.4736 -53.91 0.0006 -99.26 0.9846 -40.24 0.9 0.9595 -16.65 0.6228 -59.12 0.0011 -106.29 0.9775 -45.14 1.0 0.9497 -18.59 0.8854 -66.84 0.0020 -112.56 0.9724 -52.47 1.1 0.9473 -20.44 1.2555 -76.14 0.0033 -118.68 0.9488 -61.90 1.2 0.9442 -22.51 1.8077 -87.97 0.0057 -127.32 0.9080 -74.64 1.3 0.9428 -25.02 2.6291 -104.60 0.0094 -140.81 0.8036 -94.23 1.4 0.9291 -28.19 3.7096 -129.38 0.0150 -162.71 0.5691 -128.90 1.5 0.8949 -31.20 4.4052 -162.49 0.0199 167.72 0.2613 143.17 1.575 0.8580 -32.12 4.2251 173.74 0.0206 144.86 0.3863 57.90 1.6 0.8509 -32.20 4.0805 167.08 0.0201 139.73 0.4571 43.57 1.7 0.8322 -32.42 3.4089 145.69 0.0178 121.96 0.6747 9.53 1.8 0.8192 -33.14 2.8216 131.20 0.0163 110.98 0.7861 -9.12 1.885 0.8117 -34.05 2.4718 122.85 0.0150 105.16 0.8270 -19.02 1.9 0.8111 -34.21 2.4326 121.83 0.0146 105.00 0.8299 -20.06 2.0 0.7983 -35.49 2.1754 112.43 0.0145 100.71 0.8839 -28.30 2.3 0.7656 -39.34 1.6197 92.63 0.0129 91.76 0.9307 -47.34 2.4 0.7505 -40.82 1.4963 87.10 0.0130 88.84 0.9392 -52.37 2.5 0.7406 -42.16 1.3963 82.55 0.0125 86.98 0.9352 -56.83 3.0 0.6912 -48.25 1.0547 59.18 0.0129 83.70 0.9457 -77.19 3.5 0.6528 -50.02 0.8340 40.67 0.0137 82.89 0.9577 -94.75 4.0 0.6212 -53.48 0.6803 23.01 0.0148 83.06 0.9514 -111.12 4.5 0.5904 -57.99 0.5660 5.64 0.0162 81.74 0.9504 -126.49 5.0 0.5626 -63.00 0.4713 -11.29 0.0180 82.40 0.9579 -141.84 6.0 0.5379 -73.85 0.3100 -44.48 0.0233 83.15 0.9519 -174.05 7.0 0.5274 -87.80 0.1785 -74.89 0.0313 77.85 0.9567 159.24 8.0 0.5802 -109.03 0.0871 -100.06 0.0292 60.47 0.9583 139.16 9.0 0.4642 -159.02 0.1084 -116.73 0.0774 -6.65 0.9273 119.66 10.0 0.3145 -125.14 0.1770 135.02 0.2135 91.76 0.8623 103.49 11.0 0.4577 -156.21 0.3001 69.20 0.3397 41.97 0.7179 81.58 12.0 0.3568 -141.87 0.1551 -21.83 0.1567 -64.81 0.8292 92.01 13.0 0.5951 176.57 0.1368 19.31 0.0913 25.82 0.9341 68.61 14.0 0.7567 150.52 0.2047 9.28 0.1740 14.51 0.9165 59.31 15.0 0.8813 136.71 0.2206 0.14 0.1940 8.93 0.9168 52.67 16.0 0.9091 113.12 0.2959 -17.28 0.2823 -12.29 0.8855 36.13 17.0 0.9285 90.82 0.3197 -37.74 0.3132 -35.24 0.8701 22.96 18.0 0.8777 72.48 0.3138 -55.71 0.3095 -55.02 0.8879 12.63 19.0 0.5801 42.49 0.3116 -80.45 0.3089 -81.70 0.8591 2.20 20.0 0.9040 50.05 0.3900 -72.66 0.3890 -75.30 0.8966 -5.51 10 MGA-231T6 Scattering Parameter Measurement with Vdd = 1.8V, Idd = 4mA, L2 = 2.7nH, C2 = 47pF (Murata 0402) Freq (GHz) S11 S11 S21 S21 S12 S12 S22 S212 Mag. Ang. Mag. Ang. Mag. Ang. Mag. Ang. 0.5 0.9825 -10.15 0.0906 -37.07 0.0001 86.13 0.9960 -21.99 0.6 0.9793 -11.47 0.1661 -43.04 0.0000 105.28 0.9923 -27.93 0.7 0.9765 -13.31 0.2704 -46.77 0.0002 -106.21 0.9896 -33.11 0.8 0.9663 -15.29 0.4063 -52.89 0.0007 -101.05 0.9904 -38.70 0.825 0.9665 -15.75 0.4463 -54.48 0.0008 -102.37 0.9877 -40.10 0.9 0.9648 -17.15 0.5876 -59.88 0.0014 -107.63 0.9830 -45.00 1.0 0.9565 -19.15 0.8336 -67.85 0.0024 -113.29 0.9745 -52.43 1.1 0.9558 -21.13 1.1806 -77.33 0.0041 -119.68 0.9487 -61.69 1.2 0.9526 -23.33 1.6903 -89.41 0.0069 -128.17 0.9027 -74.29 1.3 0.9524 -26.00 2.4390 -106.13 0.0112 -141.68 0.7914 -93.29 1.4 0.9391 -29.42 3.4006 -130.68 0.0176 -163.17 0.5493 -125.98 1.5 0.9028 -32.66 4.0160 -162.73 0.0232 168.35 0.2205 148.71 1.575 0.8646 -33.73 3.8833 174.11 0.0242 146.51 0.3438 55.97 1.6 0.8564 -33.84 3.7630 167.55 0.0237 141.31 0.4174 41.76 1.7 0.8349 -34.17 3.1833 146.24 0.0214 123.70 0.6451 8.79 1.8 0.8209 -34.87 2.6573 131.61 0.0197 112.37 0.7650 -9.46 1.885 0.8131 -35.85 2.3409 123.12 0.0183 106.92 0.8116 -19.18 1.9 0.8123 -36.02 2.3042 121.97 0.0179 106.42 0.8165 -20.30 2.0 0.8002 -37.32 2.0699 112.57 0.0177 101.62 0.8725 -28.41 2.3 0.7686 -41.43 1.5526 92.26 0.0158 91.80 0.9291 -47.46 2.4 0.7548 -42.99 1.4381 86.59 0.0160 88.74 0.9396 -52.50 2.5 0.7451 -44.42 1.3436 81.95 0.0153 87.03 0.9358 -56.93 3.0 0.6979 -50.99 1.0233 58.01 0.0160 82.57 0.9459 -77.14 3.5 0.6580 -53.48 0.8159 39.03 0.0168 80.94 0.9576 -94.78 4.0 0.6245 -57.81 0.6701 20.89 0.0182 79.81 0.9540 -111.28 4.5 0.5943 -63.28 0.5618 3.19 0.0199 78.00 0.9543 -126.53 5.0 0.5684 -69.23 0.4726 -14.19 0.0221 77.59 0.9607 -141.88 6.0 0.5415 -82.60 0.3162 -48.43 0.0284 75.74 0.9560 -174.16 7.0 0.5339 -100.27 0.1857 -80.08 0.0366 69.40 0.9595 159.04 8.0 0.5945 -125.24 0.0921 -106.89 0.0329 50.49 0.9613 139.04 9.0 0.5000 -3.84 0.1101 -120.20 0.0903 164.34 0.9294 119.46 10.0 0.2489 -146.57 0.1819 132.97 0.2441 81.85 0.8589 103.44 11.0 0.4126 1.84 0.2993 64.47 0.3721 30.62 0.7145 82.67 12.0 0.2770 -159.67 0.1565 -27.13 0.1713 -74.37 0.8323 91.53 13.0 0.5459 159.23 0.1300 13.95 0.0924 15.06 0.9377 68.53 14.0 0.6920 135.03 0.1960 3.18 0.1735 3.55 0.9183 59.36 15.0 0.8035 124.06 0.2092 -4.85 0.1888 -0.19 0.9206 52.63 16.0 0.8182 101.67 0.2785 -21.97 0.2692 -20.20 0.8893 36.32 17.0 0.8337 81.30 0.3034 -42.00 0.3002 -41.91 0.8757 22.99 18.0 0.8130 64.98 0.2975 -57.51 0.2945 -58.68 0.8962 12.50 19.0 0.5099 37.02 0.2882 -81.85 0.2870 -84.34 0.8667 2.04 20.0 0.8470 45.58 0.3755 -74.73 0.3752 -78.06 0.9026 -5.60 11 Noise Parameters The Noise parameters are measured using source pull method. Figure 20 shows the input and output reference planes. The PCB is 10mils Rogers R04350. MGA-231T6 Typical Noise Parameters 25C, Freq = 1.575GHz, Vdd = 2.85V, Idd = 8mA 25C, Freq = 1.575GHz, Vdd = 2.85V, Idd = 4mA Fmin (dB) Gamma Opt Rn/50 Freq (GHz) Mag. Ang. Rn/50 0.6268 1 0.585 0.8005 24.69 0.5597 33.77 0.5286 1.575 0.655 0.775 34.98 0.4795 38.945 0.5296 2 0.645 0.776 39.835 0.4683 Freq (GHz) Fmin (dB) Gamma Opt Mag. Ang. 1 0.625 0.812 23.095 1.575 0.67 0.785 2 0.71 0.783 Package Dimensions Pin #1 Indicator R0.10 Pin #1 Dot by Marking 0.15 0.400.05 2.000.05 1.10 0.50 1.300.05 1.20 31YM 0.20 0.20 Top View Side View All units are in mm Part Number Ordering Information Part Number No. of Devices Container MGA-231T6-BLKG 100 Antistatic bag MGA-231T6-QC1 3000 7" Reel MGA-231T6-TR1G 3000 7" Reel 12 Bottom View PCB Land Patterns 1.700 1.100 0.435 1.700 1.100 0.435 0.286 0.300 0.445 0.286 0.500 0.350 1.300 0.386 0.350 0.500 0.230 0.386 0.333 0.310 PCB Land Pattern Without Via (dimension in mm) PCB Land Pattern With Via (dimension in mm) 0.435 1.700 0.435 0.260 0.500 0.510 0.260 0.230 0.230 0.310 Stencil Outline Drawing (dimension in mm) Note 1. Stencil thickness = 4 mils 13 Combined Land Pattern & Stencil Layouts (dimensions in mm) 0.286 1.960 1.700 0.260 Stencil Outline and Combined PCB Land Patterns Stencil Layout Device Orientation REEL USER FEED DIRECTION 31YM CARRIER TAPE USER FEED DIRECTION 31YM 31YM TOP VIEW END VIEW COVER TAPE Tape Dimensions 1.50 0.10 4.0 0.10 2.00 0.05 4.0 0.10 1.75 0.10 3.50 0.05 8.00 +0.30/-0.10 0.20 0.20 0.15 45 MAX. 45 MAX. 2.17 0.05 Ao Dimensions are in millimeters 14 0.73 0.05 Ko 1.67 0.05 Bo Reel Dimensions (7 inch reel) O178.01.0 FRONT BACK SEE DETAIL "X" RECYCLE LOGO FRONT VIEW 65 7.9 - 10.9* +1.5* 8.4 -0.0 45 R10.65 R5.2 Slot hole `b' BACK 60 O55.00.5 O178.01.0 FRONT Slot hole `a' EMBOSSED RIBS RAISED: 0.25mm, WIDTH: 1.25mm BACK VIEW O51.20.3 For product information and a complete list of distributors, please go to our web site: 14.4* MAX. www.avagotech.com Avago, Avago Technologies, and the A logo are trademarks of Avago Technologies in the United States and other countries. Data subject to change. Copyright (c) 2005-2012 Avago Technologies. All rights reserved. AV02-2212EN - March 2, 2012