MAX2388 at 190MHz IF for WCDMA
Abstract
Bench measurement data is provided for the MAX2387 WCDMA low-noise amplifier (LNA) and mixer for a 2140MHz RF and 190MHz IF. The IF output has been re-matched for 190MHz, and the new bill of materials is provided.
Additional Information
- Wireless Product Line Page
- Quick View Data Sheet for the MAX2387/MAX2388/MAX2389
- Applications Technical Support
Introduction to the MAX238X
The MAX2387, MAX3288, and MAX3289 are members of a family of receive front-end devices designed for WCDMA application. They integrate a low-noise amplifier (LNA) and a high-linearity downconvert mixer in an ultra-small package. The MAX2387 and MAX2388 include a local oscillator (LO) input buffer, whereas the MAX2389 eliminates the LO buffer to provide lower current consumption.
All devices feature a high-gain and low-gain mode of operation, with a 32dB gain step for the MAX2387 and an 18dB gain step for the MAX2388/MAX2389. The ICs also include a shutdown mode for powering-down the IC.
The mixer's 3rd-order nonlinearity performance can be adjusted using an external bias resistor through the BIAS_SET pin to obtain balance between desired linearity and acceptable current consumption. For the MAX2387 and MAX2388, mixer performance is optimized for a -10dBm typical drive at the LO input buffer port. The MAX2389's mixer performance is optimized for a -4dBm typical drive at the LO input port. The LO port for all versions is configurable for either single-ended or differential operation.
Measured Performance
Most of the measurement data shown below were taken on the MAX2388 with 190MHz intermediate frequency (IF) at VCC = 2.8V. The MAX2387 and MAX2389 were verified to have similar performance.
Test Conditions:
- VCC = 2.8V
- RF input power = -30dBm
- RF frequency = 2140MHz; LO frequency = 2330MHz
- Two-tone spacing = 1MHz
- LO power = -10dBm (-4dBm for MAX2389)
Parameter | High Gain | Low Gain | Units | Comments |
Gain | 14.6 | -2.8 ( -17 MAX2387) | dB | LNA input loss = 0.2dB and LNA output loss = 0.2dB have been de-embedded from the measurements. |
NF | 1.8 | 7.0 | dB | LNA input loss = 0.2dB has been de-embedded from the measurement. |
IIP3 | 3.5 | 1.0 | dBm | Measured with RF = -20dBm at low-gain mode |
S11 | -10.5 | -12.9 | dB | 10*log10( |S11| ) |
S22 | -13.5 | -16.5 | dB | 10*log10( |S22| ) |
S12 | -25.4 | -12.1 | dB | 10*log10( |S12| ) |
Icc | 9.9 | 6.8 | mA |
Parameter | High Gain | Low Gain | Units | Comments |
Gain | 10.5 | 9.5 | dB | Mixer input loss = 0.2 and IF balun insertion loss = 1.0dB have been de-embedded. |
NF | 6.8 | 6.2 | dB | Mixer input loss = 0.2dB has been de-embedded from the measurement. |
IIP3 | 10.0 | 1.8 | dBm | |
IIP2 | 17.0 | 16.8 | dBm | With single-ended LO drive |
IIP2 | 31.2 | 30.5 | dBm | With differential LO drive |
LO Leakage at IF Port | -25.5 | -25.5 | dBm | LO = -10 dBm @2330MHz MAX2387/88 |
LO Leakage at RF Port | -45 | -45 | dBm | LO = -10 dBm @2330MHz MAX2387/88 |
Frequency | S11 | S21 | S12 | S22 | ||||
(GHz) | Mag(dB) | Phase(Deg) | Mag(dB) | Phase(Deg) | Mag(dB) | Phase(Deg) | Mag(dB) | Phase(Deg) |
1.0 | -2.1286 | -58.278 | 12.847 | 133.75 | -32.155 | 74.423 | -0.945 | -23.033 |
1.1 | -2.3856 | -62.382 | 12.331 | 131.49 | -32.022 | 80.579 | -0.964 | -25.008 |
1.2 | -2.6618 | -65.862 | 12.154 | 128 | -31.585 | 73.547 | -1.089 | -24.881 |
1.3 | -2.855 | 69.138 | 11.703 | 126.22 | -30.677 | 77.068 | -1.285 | -25.903 |
1.4 | -3.1572 | -72.628 | 11.296 | 123.77 | -31.095 | 76.873 | -1.325 | -26.516 |
1.5 | -3.4104 | -75.839 | 11.253 | 120.6 | -30.572 | 75.955 | -1.467 | -26.709 |
1.6 | -3.7441 | -78.872 | 11.206 | 121.03 | -30.134 | 77.315 | -1.625 | -27.577 |
1.7 | -4.1285 | -82.259 | 10.622 | 117.69 | -30.08 | 80.001 | -1.798 | -28.049 |
1.8 | -4.3986 | -85.465 | 10.986 | 116.13 | -29.453 | 82.934 | -1.925 | -29.221 |
1.9 | -4.7755 | -89.3 | 10.436 | 115.06 | -29.922 | 83.366 | -2.098 | -29.713 |
2.0 | -5.2184 | -92.921 | 10.444 | 110.19 | -29.151 | 84.624 | -2.267 | -30.994 |
2.1 | -5.6356 | -96.942 | 10.353 | 108.99 | -28.898 | 86.776 | -2.345 | -32.867 |
2.2 | -6.0176 | -101 | 10.29 | 105.5 | -28.514 | 87.56 | -2.451 | -35.262 |
2.3 | -6.4621 | -106.27 | 10.58 | 104.32 | -27.631 | 89.437 | -2.685 | -38.079 |
2.4 | -6.9126 | -111.35 | 9.8114 | 100.88 | -27.764 | 88.93 | -2.835 | -42.528 |
2.5 | -7.2807 | -117.04 | 10.106 | 95.216 | -27.384 | 88.897 | -3.018 | -46.811 |
2.6 | -7.7233 | -122.7 | 9.7148 | 95.186 | -26.945 | 88.47 | -3.077 | -51.827 |
2.7 | -7.9908 | -130.37 | 9.0991 | 88.322 | -26.888 | 93.211 | -3.077 | -57.443 |
2.8 | -8.2315 | -137.57 | 9.6216 | 84.239 | -26.285 | 89.688 | -3.257 | -63.369 |
2.9 | -8.2342 | -144.27 | 9.0162 | 85.306 | -26.094 | 95.284 | -3.305 | -69.697 |
3.0 | -8.3826 | -151.69 | 8.5833 | 77.645 | -26.065 | 91.953 | -3.198 | -75.708 |
Mixer OIM3 versus RF Input Power
Test conditions are the same for the gain, IIP3, and NF measurements stated previously.
Mixer IIP3 versus VCC
The mixer features very high linearity with low current consumption. Feedback is the novel technique used to improve IIP3 with low current consumption. However, the feedback is optimized at VCC = 2.7V. If VCC deviates from 2.7V, IIP3 does not obtain the optimum value of approximately +12dBm. The following figure shows the IIP3 change versus VCC.
Test Setup
Bill of Materials for 190MHz IF Match of the Mixer (PDF, 11K)
MAX2387 Evaluation Kit (PDF, 45K)