19-2588; Rev 0; 9/02 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer The MAX9981 active mixers are optimized to meet the demanding requirements of GSM850, GSM900, and CDMA850 base-station receivers. These mixers provide exceptional linearity with an input IP3 of greater than +27dBm. The integrated LO driver allows for a wide range of LO drive levels from -5dBm to +5dBm. In addition, the built-in high-isolation switch enables rapid LO selection of less than 250ns, as needed for GSM transceiver designs. The MAX9981 is available in a 36-pin QFN package (6mm ✕ 6mm) with an exposed paddle, and is specified over the -40°C to +85°C extended temperature range. Features ♦ +27.3dBm Input IP3 ♦ +13.6dBm Input 1dB Compression Point ♦ 825MHz to 915MHz RF Frequency Range ♦ ♦ ♦ ♦ 70MHz to 170MHz IF Frequency Range 725MHz to 1085MHz LO Frequency Range 2.1dB Conversion Gain 10.8dB Noise Figure ♦ ♦ ♦ ♦ 42dB Channel-to-Channel Isolation -5dBm to +5dBm LO Drive +5V Single-Supply Operation Built-In LO Switch with 52dB LO1 to LO2 Isolation ♦ ESD Protection ♦ Integrated RF and LO Baluns for Single-Ended Inputs Ordering Information Applications GSM850/GSM900 2G and 2.5G EDGE BaseStation Receivers Cellular cdmaOne™ and cdma2000™ BaseStation Receivers PART TEMP RANGE MAX9981EGX-T *EP = Exposed paddle. Pin Configuration/ Functional Diagram GND GND IFMAIN+ IFMAIN- GND VCC GND GND 35 34 33 32 31 30 29 28 1 TAPMAIN 2 MAINBIAS 3 25 GND GND 4 24 GND GND 5 23 LOSEL GND 6 22 GND DIVBIAS 7 21 VCC TAPDIV 8 20 GND RFDIV 9 19 LO1 27 LO2 13 14 15 16 17 18 IFDIV+ IFDIV- GND VCC GND GND 11 GND 26 GND 12 10 MAX9981 GND iDEN is a trademark of Motorola, Inc. RFMAIN VCC cdma2000 is a trademark of Telecommunications Industry Association. VCC TOP VIEW Microwave Point-to-Point Links cdmaOne is a trademark of CDMA Development Group. 36 TDMA and Integrated Digital Enhanced Network (iDEN)™ Base-Station Receivers Digital and Spread-Spectrum Communication Systems PIN-PACKAGE -40°C to +85°C 36 QFN-EP* (6mm × 6mm) 6mm x 6mm QFN-EP ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX9981 General Description The MAX9981 dual high-linearity mixer integrates a local oscillator (LO) switch, LO buffer, LO splitter, and two active mixers. On-chip baluns allow for single-ended RF and LO inputs. The active mixers eliminate the need for an additional IF amplifier because the mixer provides a typical overall conversion gain of 2.1dB. MAX9981 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer ABSOLUTE MAXIMUM RATINGS VCC ........................................................................-0.3V to +5.5V IFMAIN+, IFMAIN-, IFDIV+, IFDIV-, MAINBIAS, DIVBIAS, LOSEL..................-0.3V to (VCC + 0.3V) TAPMAIN, TAPDIV ..............................................................+5.5V MAINBIAS, DIVBIAS Current ................................................5mA RFMAIN, RFDIV, LO1, LO2 Input Power ........................+20dBm Continuous Power Dissipation (TA = +70°C) 36-Pin QFN (derate 33mW/°C above +70°C)..............2200mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS (Typical Application Circuit, VCC = +4.75V to +5.25V, no RF signals applied, all RF inputs and outputs terminated with 50Ω, 267Ω resistors connected from MAINBIAS and DIVBIAS to GND, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +5.0V, TA = +25°C, unless otherwise noted.) PARAMETER MIN TYP MAX UNITS VCC 4.75 5.00 5.25 V Supply Current ICC 260 291 325 mA Input High Voltage VIH 3.5 Input Low Voltage VIL 0.4 V +5 µA Supply Voltage LOSEL Input Current SYMBOL CONDITIONS ILOSEL V -5 AC ELECTRICAL CHARACTERISTICS (Typical Application Circuit, VCC = +4.75V to +5.25V, PLO = -5dBm to +5dBm, fRF = 825MHz to 915MHz, fLO = 725MHz to 1085MHz, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +5.0V, PRF = -5dBm, PLO = 0dBm, fRF = 870MHz, fLO = 770MHz, TA = +25°C, unless otherwise noted.) (Notes 1, 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS RF Frequency fRF 825 915 MHz LO Frequency fLO 725 1085 MHz 70 170 MHz -5 +5 dBm IF Frequency LO Drive Level Conversion Gain (Note 3) fIF Must meet RF and LO frequency range. IF matching components affect IF frequency range. PLO GC VCC = +5.0V, fIF = 100MHz, low-side injection, PRF = 0dBm, PLO = -5dBm Cellular band, fRF = 825MHz to 850MHz 2.7 GSM band, fRF = 880MHz to 915MHz 2.1 Gain Variation from Nominal fRF = 825MHz to 915MHz, 3σ Conversion Loss from LO to IF Inject PIN = -20dBm at fLO + 100MHz into LO port. Measure 100MHz at IF port as POUT. No RF signal at RF port. Noise Figure 100MHz IF, low-side injection 2 NF dB ±0.6 dB 53 dB Cellular band, fRF = 825MHz to 850MHz 10.8 GSM band, fRF = 880MHz to 915MHz 11.9 dB _______________________________________________________________________________________ 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer (Typical Application Circuit, VCC = +4.75V to +5.25V, PLO = -5dBm to +5dBm, fRF = 825MHz to 915MHz, fLO = 725MHz to 1085MHz, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +5.0V, PRF = -5dBm, PLO = 0dBm, fRF = 870MHz, fLO = 770MHz, TA = +25°C, unless otherwise noted.) (Notes 1, 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input 1dB Compression Point P1dB Low-side injection Input Third-Order Intercept Point IIP3 PLO = -5dBm to +5dBm (Notes 3, 4) 2 RF - 2 LO Spur Rejection 2×2 fRF = 915MHz, fLO = 815MHz, fSPUR = 865MHz, PRF = -5dBm 3 RF - 3 LO Spur Rejection 3×3 fRF = 915MHz, fLO = 815MHz, fSPUR = 848.3MHz, PRF = -5dBm 79.7 dBc Maximum LO Leakage at RF Port PLO = -5dBm to +5dBm, fLO = 725MHz to 1100MHz -42 dBm Maximum LO Leakage at IF Port PLO = -5dBm to +5dBm, fLO = 725MHz to 1100MHz -30.6 dBm Minimum RF to IF Isolation PLO = -5dBm to +5dBm, fRF = 825MHz to 915MHz 18 dB LO1 to LO2 Isolation fRF = 825MHz to 915MHz, PLO1 = PLO2 = +5dBm, fIF = 100MHz (Note 5) 52 dB Minimum Channel Isolation LO Switching Time fRF = 825MHz to 915MHz, fLO = 725MHz to 1085MHz IF Return Loss Note 1: Note 2: Note 3: Note 4: Note 5: Note 6: dBm 27.3 dBm Main 53.3 Diversity 43.2 PRFMAIN = -5dBm, RFDIV terminated with 50Ω. Measured power at IFDIV relative to IFMAIN. dBc 39.5 dBc PRFDIV = -5dBm, RFMAIN terminated with 50Ω. Measured power at IFMAIN relative to IFDIV. 50% of LOSEL to IF settled within 2° RF Return Loss LO Return Loss 13.6 LO port selected LO port unselected RF and LO terminated into 50Ω, fIF = 100MHz (Note 6) 42 250 ns 25 dB 19 14.3 15 dB dB Guaranteed by design and characterization. All limits reflect losses of external components. Output measurements taken at IF OUT of Typical Application Circuit. Production tested. Two tones at 1MHz spacing, -5dBm per tone at RF port. Measured at IF port at IF frequency. fLO1 and fLO2 are offset by 1MHz. IF return loss can be optimized by external matching components. _______________________________________________________________________________________ 3 MAX9981 AC ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (Typical Application Circuit, VCC = 5.0V, PRF = -5dBm, PLO = 0dBm, TA = +25°C, unless otherwise noted.) 2 TA = +85°C 1 5 3 2 PLO = -5dBm, 0dBm, +5dBm MAX9981 toc03 CONVERSION GAIN vs. RF FREQUENCY LOW-SIDE INJECTION fIF = 100MHz MAIN MIXER 4 CONVERSION GAIN (dB) 3 fIF = 100MHz MAIN MIXER 4 CONVERSION GAIN (dB) 4 CONVERSION GAIN (dB) fIF = 100MHz MAIN MIXER TA = -40°C 5 MAX9981 toc01 5 CONVERSION GAIN vs. RF FREQUENCY LOW-SIDE INJECTION MAX9981 toc02 CONVERSION GAIN vs. RF FREQUENCY LOW-SIDE INJECTION 1 3 2 VCC = 4.75V, 5.0V, 5.25V 1 TA = +25°C 0 0 820 840 860 880 920 0 820 860 880 900 920 820 840 860 880 900 920 CONVERSION GAIN vs. RF FREQUENCY HIGH-SIDE INJECTION CONVERSION GAIN vs. RF FREQUENCY HIGH-SIDE INJECTION CONVERSION GAIN vs. RF FREQUENCY HIGH-SIDE INJECTION 2 MAX9981 toc05 5 3 2 PLO = -5dBm, 0dBm, +5dBm 1 860 2 VCC = 4.75V, 5.0V, 5.25V 1 0 840 3 TA = +25°C 0 820 fIF = 120MHz MAIN MIXER 4 CONVERSION GAIN (dB) 3 fIF = 120MHz MAIN MIXER 4 CONVERSION GAIN (dB) TA = -40°C TA = +85°C 5 MAX9981 toc04 fIF = 120MHz MAIN MIXER MAX9981 toc06 RF FREQUENCY (MHz) 1 880 900 920 0 820 840 860 880 900 920 820 840 860 880 900 920 2 RF - 2 LO RESPONSE vs. RF FREQUENCY LOW-SIDE INJECTION 2 RF - 2 LO RESPONSE vs. RF FREQUENCY LOW-SIDE INJECTION 2 RF - 2 LO RESPONSE vs. RF FREQUENCY LOW-SIDE INJECTION 70 65 TA = +25°C 60 55 TA = -40°C 85 fIF = 100MHz MAIN MIXER PRF = -5dBm PLO = -5dBm 75 65 PLO = 0dBm 55 50 840 860 880 RF FREQUENCY (MHz) 900 920 70 65 60 55 VCC = 4.75V, 5.0V, 5.25V 45 45 820 fIF = 100MHz MAIN MIXER PRF = -5dBm 75 50 PLO = +5dBm 45 80 2 RF - 2 LO RESPONSE (dBc) 75 fIF = 100MHz MAIN MIXER PRF = -5dBm 2 RF - 2 LO RESPONSE (dBc) TA = +85°C MAX9981 toc09 RF FREQUENCY (MHz) MAX9981 toc08 RF FREQUENCY (MHz) MAX9981 toc07 RF FREQUENCY (MHz) 80 4 840 RF FREQUENCY (MHz) 4 CONVERSION GAIN (dB) 900 RF FREQUENCY (MHz) 5 2 RF - 2 LO RESPONSE (dBc) MAX9981 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer 820 840 860 880 RF FREQUENCY (MHz) 900 920 820 840 860 880 RF FREQUENCY (MHz) _______________________________________________________________________________________ 900 920 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer 50 TA = +25°C 45 55 50 PLO = 0dBm 45 40 820 840 860 880 fIF = 100MHz DIVERSITY MIXER PRF = -5dBm MAX9981 toc12 60 55 50 VCC = 4.75V, 5.0V, 5.25V 45 PLO = -5dBm TA = -40°C 900 920 40 820 840 860 880 900 920 820 840 860 880 900 920 RF FREQUENCY (MHz) RF FREQUENCY (MHz) RF FREQUENCY (MHz) 2 LO - 2 RF RESPONSE vs. RF FREQUENCY HIGH-SIDE INJECTION 2 LO - 2 RF RESPONSE vs. RF FREQUENCY HIGH-SIDE INJECTION 2 LO - 2 RF RESPONSE vs. RF FREQUENCY HIGH-SIDE INJECTION TA = +85°C 60 55 TA = +25°C 50 58 PLO = 0dBm 56 PLO = -5dBm 54 60 TA = -40°C 860 880 900 56 VCC = 5.25V 54 VCC = 4.75, 5.0V 50 50 840 58 PLO = +5dBm 45 820 fIF = 120MHz MAIN MIXER PRF = -5dBm 52 52 MAX9981 toc15 fIF = 120MHz MAIN MIXER PRF = -5dBm 2 LO - 2 RF RESPONSE (dBc) 65 60 MAX9981 toc14 fIF = 120MHz MAIN MIXER PRF = -5dBm 2 LO - 2 RF RESPONSE (dBc) MAX9981 toc13 70 920 820 840 860 880 900 820 920 840 860 880 900 920 RF FREQUENCY (MHz) 2 LO - 2 RF RESPONSE vs. RF FREQUENCY HIGH-SIDE INJECTION 2 LO - 2 RF RESPONSE vs. RF FREQUENCY HIGH-SIDE INJECTION 2 LO - 2 RF RESPONSE vs. RF FREQUENCY HIGH-SIDE INJECTION fIF = 120MHz DIVERSITY MIXER PRF = -5dBm 46 45 TA = +85°C 44 TA = +25°C 43 42 TA = -40°C 52.5 2 LO - 2 RF RESPONSE (dBc) 47 50.0 fIF = 120MHz DIVERSITY MIXER PRF = -5dBm PLO = 0dBm PLO = +5dBm 47.5 45.0 42.5 46 fIF = 120MHz DIVERSITY MIXER PRF = -5dBm 45 44 VCC = 5.25V 43 40.0 41 MAX9981 toc18 RF FREQUENCY (MHz) MAX9981 toc16 RF FREQUENCY (MHz) 2 LO - 2 RF RESPONSE (dBc) 2 LO - 2 RF RESPONSE (dBc) MAX9981 toc11 PLO = +5dBm 40 2 LO - 2 RF RESPONSE (dBc) fIF = 100MHz DIVERSITY MIXER PRF = -5dBm 2 RF - 2 LO RESPONSE vs. RF FREQUENCY LOW-SIDE INJECTION 2 RF - 2 LO RESPONSE (dBc) 55 60 MAX9981 toc17 2 RF - 2 LO RESPONSE (dBc) TA = +85°C fIF = 100MHz DIVERSITY MIXER PRF = -5dBm 2 RF - 2 LO RESPONSE vs. RF FREQUENCY LOW-SIDE INJECTION 2 RF - 2 LO RESPONSE (dBc) 60 MAX9981 toc10 2 RF - 2 LO RESPONSE vs. RF FREQUENCY LOW-SIDE INJECTION VCC = 4.75V, 5.0V PLO = -5dBm 40 37.5 820 840 860 880 RF FREQUENCY (MHz) 900 920 42 820 840 860 880 RF FREQUENCY (MHz) 900 920 820 840 860 880 900 920 RF FREQUENCY (MHz) _______________________________________________________________________________________ 5 MAX9981 Typical Operating Characteristics (continued) (Typical Application Circuit, VCC = 5.0V, PRF = -5dBm, PLO = 0dBm, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (Typical Application Circuit, VCC = 5.0V, PRF = -5dBm, PLO = 0dBm, TA = +25°C, unless otherwise noted.) 29 INPUT IP3 (dBm) 27 27 26 25 860 27 VCC = 5.0V 26 PLO = -5dBm 25 840 28 PLO = 0dBm TA = +25°C 820 fIF = 100MHz MAIN MIXER VCC = 5.25V 28 TA = -40°C 880 920 900 VCC = 4.75V 25 820 840 860 880 900 920 820 840 860 880 900 920 RF FREQUENCY (MHz) RF FREQUENCY (MHz) INPUT IP3 vs. RF FREQUENCY HIGH-SIDE INJECTION INPUT IP3 vs. RF FREQUENCY HIGH-SIDE INJECTION INPUT IP3 vs. RF FREQUENCY HIGH-SIDE INJECTION TA = -40°C fIF = 120MHz MAIN MIXER 29 30 MAX9981 toc23 29 30 MAX9981 toc22 fIF = 120MHz MAIN MIXER fIF = 120MHz MAIN MIXER VCC = 5.25V 29 28 27 INPUT IP3 (dBm) INPUT IP3 (dBm) PLO = -5dBm 28 27 PLO = 0dBm MAX9981 toc24 RF FREQUENCY (MHz) 30 INPUT IP3 (dBm) 30 PLO = +5dBm 28 26 fIF = 100MHz MAIN MIXER 29 TA = +85°C INPUT IP3 (dBm) INPUT IP3 (dBm) 29 30 INPUT IP3 vs. RF FREQUENCY LOW-SIDE INJECTION MAX9981 toc21 fIF = 100MHz MAIN MIXER MAX9981 toc19 30 INPUT IP3 vs. RF FREQUENCY LOW-SIDE INJECTION MAX9981 toc20 INPUT IP3 vs. RF FREQUENCY LOW-SIDE INJECTION VCC = 5.0V 28 27 TA = +25°C 26 26 26 PLO = +5dBm TA = +85°C 25 840 860 880 900 920 25 820 840 860 880 900 920 820 840 860 880 900 920 RF FREQUENCY (MHz) RF FREQUENCY (MHz) INPUT P1dB vs. RF FREQUENCY LOW-SIDE INJECTION INPUT P1dB vs. RF FREQUENCY LOW-SIDE INJECTION INPUT P1dB vs. RF FREQUENCY LOW-SIDE INJECTION TA = +85°C TA = +25°C 14 13 15 MAX9981 toc26 PLO = -5dBm PLO = 0dBm 14 13 860 880 15 VCC = 5.25V VCC = 5.0V 14 VCC = 4.75V 12 RF FREQUENCY (MHz) 16 PLO = +5dBm 12 840 fIF = 100MHz MAIN MIXER 13 TA = -40°C 820 17 INPUT P1dB (dBm) 15 fIF = 100MHz MAIN MIXER 16 INPUT P1dB (dBm) 16 17 MAX9981 toc25 fIF = 100MHz MAIN MIXER 900 920 MAX9981 toc27 RF FREQUENCY (MHz) 17 6 VCC = 4.75V 25 820 INPUT P1dB (dBm) MAX9981 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer 12 820 840 860 880 RF FREQUENCY (MHz) 900 920 820 840 860 880 RF FREQUENCY (MHz) _______________________________________________________________________________________ 900 920 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer 15 14 fIF = 120MHz MAIN MIXER 16 13 17 16 PLO = -5dBm VCC = 5.25V 15 14 PLO = 0dBm 13 fIF = 120MHz MAIN MIXER MAX9981 toc30 TA = +85°C TA = +25°C INPUT P1dB (dBm) INPUT P1dB (dBm) 16 17 INPUT P1dB (dBm) fIF = 120MHz MAIN MIXER MAX9981 toc28 17 INPUT P1dB vs. RF FREQUENCY HIGH-SIDE INJECTION INPUT P1dB vs. RF FREQUENCY HIGH-SIDE INJECTION MAX9981 toc29 INPUT P1dB vs. RF FREQUENCY HIGH-SIDE INJECTION PLO = +5dBm VCC = 5.0V 15 14 VCC = 4.75V 13 TA = -40°C 12 840 860 880 920 900 820 840 860 880 900 820 920 840 860 880 900 920 RF FREQUENCY (MHz) RF FREQUENCY (MHz) CHANNEL ISOLATION vs. RF FREQUENCY LOW-SIDE INJECTION CHANNEL ISOLATION vs. RF FREQUENCY LOW-SIDE INJECTION CHANNEL ISOLATION vs. RF FREQUENCY LOW-SIDE INJECTION TA = +85°C 45 40 TA = +25°C 55 MAX9981 toc32 RF MAIN IN/IF DIVERSITY OUT fIF = 100MHz CHANNEL ISOLATION (dBc) CHANNEL ISOLATION (dBc) 50 55 MAX9981 toc31 RF MAIN IN/IF DIVERSITY OUT fIF = 100MHz 50 45 40 RF DIVERSITY IN/IF MAIN OUT fIF = 100MHz MAX9981 toc33 RF FREQUENCY (MHz) 55 CHANNEL ISOLATION (dBc) 12 12 820 50 45 40 PLO = -5dBm, 0dBm, +5dBm PLO = -5dBm, 0dBm, +5dBm TA = -40°C 35 35 820 840 880 900 920 35 820 840 860 880 900 920 820 840 860 880 900 920 RF FREQUENCY (MHz) RF FREQUENCY (MHz) CHANNEL ISOLATION vs. RF FREQUENCY HIGH-SIDE INJECTION CHANNEL ISOLATION vs. RF FREQUENCY HIGH-SIDE INJECTION CHANNEL ISOLATION vs. RF FREQUENCY HIGH-SIDE INJECTION TA = +85°C 45 TA = +25°C 40 55 MAX9981 toc35 RF MAIN IN/IF DIVERSITY OUT fIF = 120MHz CHANNEL ISOLATION (dBc) CHANNEL ISOLATION (dBc) 50 55 MAX9981 toc34 RF MAIN IN/IF DIVERSITY OUT fIF = 120MHz 50 45 40 RF DIVERSITY IN/IF MAIN OUT fIF = 120MHz MAX9981 toc36 RF FREQUENCY (MHz) 55 CHANNEL ISOLATION (dBc) 860 50 45 40 PLO = -5dBm, 0dBm, +5dBm PLO = -5dBm, 0dBm, +5dBm TA = -40°C 35 35 820 840 860 880 RF FREQUENCY (MHz) 900 920 35 820 840 860 880 RF FREQUENCY (MHz) 900 920 820 840 860 880 900 920 RF FREQUENCY (MHz) _______________________________________________________________________________________ 7 MAX9981 Typical Operating Characteristics (continued) (Typical Application Circuit, VCC = 5.0V, PRF = -5dBm, PLO = 0dBm, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (Typical Application Circuit, VCC = 5.0V, PRF = -5dBm, PLO = 0dBm, TA = +25°C, unless otherwise noted.) 54 53 TA = +25°C TA = +-40°C 52 55 LO OFFSET 1MHz fIF = 100MHz DIVERSITY MIXER PLO = -5dBm 54 53 PLO = 0dBm 52 LO SWITCH ISOLATION vs. RF FREQUENCY HIGH-SIDE INJECTION 56 MAX9981 toc39 TA = +85°C 56 MAX9981 toc38 LO OFFSET 1MHz fIF = 100MHz DIVERSITY MIXER LO SWITCH ISOLATION (dBc) 55 MAX9981 toc37 LO SWITCH ISOLATION (dBc) 56 LO SWITCH ISOLATION vs. RF FREQUENCY LOW-SIDE INJECTION LO SWITCH ISOLATION (dBc) LO SWITCH ISOLATION vs. RF FREQUENCY LOW-SIDE INJECTION LO OFFSET 1MHz fIF = 120MHz MAIN MIXER 55 TA = +85°C 54 53 52 PLO = +5dBm TA = -40°C TA = +25°C 51 51 840 860 880 920 900 820 840 860 880 920 900 820 840 860 880 RF FREQUENCY (MHz) LO LEAKAGE AT IF PORT vs. LO FREQUENCY LO LEAKAGE AT IF PORT vs. LO FREQUENCY LO LEAKAGE AT RF PORT vs. LO FREQUENCY TA = +25°C -36 -39 PLO = 0dBm PLO = +5dBm -33 MAIN MIXER -36 PLO = -5dBm -45 -50 -55 -60 PLO = 0dBm -65 PLO = +5dBm TA = -40°C -42 -39 PLO = -5dBm -45 -42 800 850 900 950 1000 800 850 900 950 1000 700 1100 RF TO IF ISOLATION vs. RF FREQUENCY NOISE FIGURE vs. RF FREQUENCY LOW-SIDE INJECTION 18 TA = -40°C 15 MAX9981 toc44 PLO = 0dBm, +5dBm 22 880 RF FREQUENCY (MHz) 900 920 fIF = 100MHz MAIN MIXER 14 24 13 TA = +85°C 12 11 10 20 TA = +25°C 9 18 860 15 NOISE FIGURE (dB) TA = +25°C MAIN MIXER RF TO IF ISOLATION (dB) TA = +85°C 21 26 MAX9981 toc45 RF TO IF ISOLATION vs. RF FREQUENCY PLO = -5dBm 8 1000 LO FREQUENCY (MHz) 27 840 900 LO FREQUENCY (MHz) MAIN MIXER 820 800 LO FREQUENCY (MHz) 30 24 -70 750 MAX9981 toc43 750 MAX9981 toc42 -30 -40 LO LEAKAGE (dBm) -33 MAIN MIXER LO LEAKAGE (dBm) TA = +85°C -27 MAX9981 toc41 MAIN MIXER 920 900 RF FREQUENCY (MHz) -30 LO LEAKAGE (dBm) 51 RF FREQUENCY (MHz) MAX9981 toc40 820 RF TO IF ISOLATION (dB) MAX9981 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer TA = -40°C 8 820 840 860 880 RF FREQUENCY (MHz) 900 920 820 840 860 880 RF FREQUENCY (MHz) _______________________________________________________________________________________ 900 920 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer 15 20 25 LO RETURN LOSS vs. LO FREQUENCY MAX9981 toc47 0 MAIN MIXER SET BY EXTERNAL MATCHING 5 LO INPUT SELECTED 5 LO RETURN LOSS (dB) IF RETURN LOSS (dB) PLO = -5dBm, 0dBm, +5dBm 10 15 10 PLO = -5dBm 15 20 25 PLO = 0dBm 30 30 PLO = +5dBm 35 20 800 900 1000 1100 50 75 RF FREQUENCY (MHz) 100 125 150 200 175 800 1000 1100 SUPPLY CURRENT vs. TEMPERATURE 320 310 SUPPLY CURRENT (mA) LO INPUT UNSELECTED 5 900 LO FREQUENCY (MHz) LO RETURN LOSS vs. LO FREQUENCY 0 10 15 20 PLO = -5dBm, 0dBm, +5dBm 25 700 IF FREQUENCY (MHz) MAX9981 toc49 700 VCC = 5.25V 300 VCC = 5.0V 290 280 270 30 35 MAX9981 toc50 35 LO RETURN LOSS (dB) RF RETURN LOSS (dB) 5 10 IF RETURN LOSS vs. IF FREQUENCY 0 MAX9981 toc46 MAIN MIXER MAX9981 toc48 RF RETURN LOSS vs. RF FREQUENCY 0 VCC = 4.75V 260 700 800 900 1000 LO FREQUENCY (MHz) 1100 -40 -15 10 35 60 85 TEMPERATURE (°C) _______________________________________________________________________________________ 9 MAX9981 Typical Operating Characteristics (continued) (Typical Application Circuit, VCC = 5.0V, PRF = -5dBm, PLO = 0dBm, TA = +25°C, unless otherwise noted.) 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer MAX9981 Pin Description PIN NAME FUNCTION Main Channel RF Input. This input is internally matched to 50Ω and is DC shorted to ground through a balun. 1 RFMAIN 2 TAPMAIN Main RF Balun Center Tap. Connect bypass capacitors from this pin to ground. 3 MAINBIAS Bias control for the Main Mixer. Connect a 267Ω resistor from this pin to ground to set the bias current for the main mixer. 4, 5, 6, 11, 12, 15, 17, 18, 20, 22, 24, 25, 26, 28, 29, 31, 34, 35, EP GND 7 DIVBIAS Bias Control for the Diversity Mixer. Connect a 267Ω resistor from this pin to ground to set the bias current for the diversity mixer. 8 TAPDIV Diversity RF Balun Center Tap. Connect bypass capacitors from this pin to ground. 9 RFDIV 10, 16, 21, 30, 36 VCC 13, 14 IFDIV+, IFDIV- 19 LO1 23 LOSEL 27 LO2 32, 33 IFMAIN-, IFMAIN+ 10 Ground Diversity Channel RF Input. This input is internally matched to 50Ω and is DC shorted to ground through a balun. Power-Supply Connections. Connect bypass capacitors as shown in the Typical Application Circuit. Differential IF Output for Diversity Mixer. Connect 560nH pullup inductors and 137Ω pullup resistors from each of these pins to VCC for a 70MHz to 100MHz IF range. Local Oscillator Input 1. This input is internally matched to 50Ω and is DC shorted to ground through a balun. Local Oscillator Select. Set this pin to logic HIGH to select LO1; set to logic LOW to select LO2. Local Oscillator Input 2. This input is internally matched to 50Ω and is DC shorted to ground through a balun. Differential IF Output for the Main Mixer. Connect 560nH pullup inductors and 137Ω pullup resistors from each of these pins to VCC for a 70MHz to 100MHz IF range. ______________________________________________________________________________________ 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer C14 L1 3 R3 T1 6 IFMAIN_OUT 5.0V 2 C13 4:1 (200:50) TRANSFORMER C16 L2 4 1 R4 C15 5.0V 5.0V C5 C1 RFMAIN RF_MAIN TAPMAIN C11 C2 R1 MAINBIAS GND GND R2 GND DIVBIAS C12 C3 TAPDIV RFDIV RF_DIV GND 28 GND 29 30 31 VCC GND IFMAIN32 IFMAIN+ 33 GND 34 GND 35 36 VCC C10 C8 1 27 MAX9981 2 26 3 25 4 24 5 23 6 22 7 21 8 20 9 19 LO2 LO2 GND GND GND LOSEL LO SELECT GND 5.0V VCC GND LO1 LO1 C7 18 GND GND 17 16 VCC GND 15 14 IFDIV- 13 IFDIV+ 11 12 GND 5.0V GND VCC 10 C4 5.0V C6 C9 C19 L4 3 R6 T2 6 IFDIV_OUT 5.0V C17 C20 L3 R5 2 4:1 (200:50) TRANSFORMER 1 4 C18 ______________________________________________________________________________________ 11 MAX9981 Typical Application Circuit 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer MAX9981 Component List COMPONENT VALUE SIZE C1, C4 33pF 0603 C2, C3 3.9pF 0603 Murata GRM1885C1H3R9C C5, C6, C9, C10 100pF 0603 Murata GRM1885C1H101J C7, C8 15pF 0603 Murata GRM1885C1H150J C11, C12 0.033µF 0603 Murata GRM188R71E333K C13, C16, C17, C20 220pF 0603 Murata GRM1885C1H221J C14, C15, C18, C19 330pF 0603 Murata GRM1885C1H331J L1–L4 560nH 1008 CoilCraft 1008CS-561XJBB R1, R2 267Ω ±1% 0603 — R3–R6 137Ω ±1% 0603 — T1, T2 4:1 (200:50) — Detailed Description The MAX9981 downconverter mixers are designed for GSM and CDMA base-station receivers with an RF frequency between 825MHz and 915MHz. Each active mixer provides 2.1dB to 2.7dB of overall conversion gain to the receive signal, removing the need for an external IF amplifier. The mixers have excellent input IP3 measuring greater than +27dBm. The device also features integrated RF and LO baluns that allow the mixers to be driven with single-ended signals. RF Inputs The MAX9981 has two RF inputs (RFMAIN, RFDIV) that are internally matched to 50Ω requiring no external matching components. A 33pF DC-blocking capacitor is required at the input since the input is internally DC shorted to ground through a balun. Return loss is better than 15dB over the entire frequency range of 825MHz to 915MHz. LO Inputs The mixers can be used for either high-side or low-side injection applications with an LO frequency range of 725MHz to 1085MHz. An internal LO switch allows for switching between two single-ended LO ports. This is useful for fast frequency changes/frequency hopping. LO switching time is less than 250ns. The switch is controlled by a digital input (LOSEL) that when high, selects LO1 and when low, selects LO2. The selected LO input mixes with both RFMAIN and RFDIV to produce the IF signals. Internal LO buffers allow for a wide power range on the LO ports. The LO signal power can vary from -5dBm to +5dBm. LO1 and LO2 are internally matched to 50Ω, so only a 15pF DC-blocking capacitor is required at each LO port. 12 PART NUMBER Murata GRM1885C1H330J Mini-Circuits TC4-1W-7A IF Outputs Each mixer has an IF frequency range of 70MHz to 170MHz. The differential IF output ports require external pullup inductors to VCC to resonate out the differential on-chip capacitance of 1.8pF. See the Typical Application Circuit for recommended component values for an IF of 70MHz to 100MHz. The IF match can be optimized for higher IF frequencies by reducing the values of the pullup inductors L1, L2, L3, and L4. Note: Removing the ground plane from underneath these inductors reduces parasitic capacitive loading and improves VSWR. Bias Circuitry Connect bias resistors from MAINBIAS and DIVBIAS to ground to set the mixer bias current. A nominal resistor value of 267Ω sets an input IP3 of +27dBm and supply current of 290mA. Bias currents are fine-tuned at the factory and should not be adjusted. Applications Information Layout Considerations A properly designed PC board is an essential part of any RF/microwave circuit. Keep RF signal lines as short as possible to reduce losses, radiation, and inductance. For best performance, route the ground pin traces directly to the exposed paddle underneath the package. This paddle should be connected to the ground plane of the board by using multiple vias under the device to provide the best RF/thermal conduction path. Solder the exposed paddle, on the bottom of the device package, to a PC board exposed pad. ______________________________________________________________________________________ 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer Chip Information TRANSISTOR COUNT: 358 PROCESS: BiCMOS ______________________________________________________________________________________ 13 MAX9981 Power Supply Bypassing Proper voltage supply bypassing is essential for high-frequency circuit stability. Bypass each VCC pin, TAPMAIN, and TAPDIV with the capacitors shown in the typical application circuit. Place the TAPMAIN and TAPDIV bypass capacitors to ground within 100mils of the TAPMAIN and TAPDIV pins. Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) 36L,40L, QFN.EPS MAX9981 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer 14 ______________________________________________________________________________________ 825MHz to 915MHz, Dual SiGe High-Linearity Active Mixer Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX9981 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)