RF2461_1 RFMD | Alldatasheet
Document overview
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Technical content
Features
Complete Receiver Front-End Stepped LNA/Mixer Gain Con- trol Adjustable LNA/Mixer Bias Current Adjustable LNA/Mixer IIP3 Meets IMD Tests with Three Gain States/Two Logic Con- trol Lines
Applications
CDMA/FM (AMPS) Systems Dual-Mode TACS/JCDMA Sys- tems General Purpose Downcon- verter Commercial and Consumer Systems Portable Battery-Powered Equipment RF2461CDMA/FM Low Noise Amplifier/Mixer 900MHz Downconverter RF2461PCBA-41X Fully Assembled Evaluation Board Rev B6 DS060925 RoHS Compliant & Pb-Free Product Package: QFN, 20-Pin, 4x4
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Absolute Maximum Ratings Parameter Rating Unit Supply Voltage -0.5 to +5.0 V DC Input LO and RF Levels +6 dBm Operating Ambient Temperature -40 to +85 °C Storage Temperature -40 to +150 °C Parameter Specification Unit ConditionMin. Typ. Max. Overall T=25°C, V CC=3.0V RF Frequency Range 800 869 to 894 1000 MHz 832 to 870 LO Frequency Range 700 954 to 979 1000 MHz 722 to 760 IF Frequency Range 0.1 250 MHz Power Down Current 10 μA LNA - CDMA/JCDMA LNA Gain=1 Gain 14.0 15.0 16.0 dB IPSET=1 13.5 14.5 15.0 dB IPSET=0 Noise Figure 1.8 2 dB IPSET=1 1.8 2 dB IPSET=0 Input IP3 +9.0 +11.0 dBm IPSET=1 +7.0 +9.0 dBm IPSET=0 Current 6.5 mA IPSET=1 5.0 mA IPSET=0 LNA Bypass - CDMA/JCDMA LNA Gain=0 Gain -8 -6 dB Noise Figure 6 8 dB Input IP3 +16.0 +18.0 dBm Current 0 mA Mixer - CDMA 3kΩ balanced load. IIP3 is adjustable. Decreasing R4/R5 will increase IIP3. LO=965MHz@-10dBm, IF=85.38MHz Gain 13 14.5 dB Mixer Preamp ON, Mix Gain=1 4 5.8 dB Mixer Preamp OFF, Mix Gain=0 Noise Figure 5.5 7 dB Mixer Preamp ON, Mix Gain=1 13 14 dB Mixer Preamp OFF, Mix Gain=0 Input IP3 +3.0 +4.0 dBm Mixer Preamp ON, Mix Gain=1 +13.0 +14.0 dBm Mixer Preamp OFF, Mix Gain=0 Current 21 mA Mixer Preamp ON, Mix Gain=1 18 mA Mixer Preamp OFF, Mix Gain=0 Mixer - JCDMA 3kΩ balanced load. IIP3 is adjustable. Decreasing R4/R5 will increase IIP3. LOIN=741MHz@-4dBm, IF=110MHz Caution! ESD sensitive device. Exceeding any one or a combination of the Absolute Maximum Rating conditions may cause permanent damage to the device. Extended application of Absolute Maximum Rating conditions to the device may reduce device reliability. Specified typical perfor- mance or functional operation of the device under Absolute Maximum Rating condi- tions is not implied. RoHS status based on EUDirective2002/95/EC (at time of this document revision). The information in this publication is believed to be accurate and reliable. However, no responsibility is assumed by RF Micro Devices, Inc. ("RFMD") for its use, nor for any infringement of patents, or other rights of third parties, resulting from its use. No license is granted by implication or otherwise under any patent or patent rights of RFMD. RFMD reserves the right to change component circuitry, recommended appli- cation circuitry and specifications at any time without prior notice.
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Gain 12 13 dB Mixer Preamp ON, Mix Gain=1 2.5 4.0 dB Mixer Preamp OFF, Mix Gain=0 Noise Figure 5.5 7 dB Mixer Preamp ON, Mix Gain=1 13 14 dB Mixer Preamp OFF, Mix Gain=0 Input IP3 +2.0 +3.0 dBm Mixer Preamp ON, Mix Gain=1 +10.0 +12.0 dBm Mixer Preamp OFF, Mix Gain=0 Current 24 mA Mixer Preamp ON, Mix Gain=1 21 mA Mixer Preamp OFF, Mix Gain=0
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Parameter Specification Unit ConditionMin. Typ. Max. Local Oscillator Input Input Level -10 dBm LO to IF Isolation -70 dB LO to LNA Isolation -60 dB Any gain state. Power Supply Voltage 2.65 3.0 3.15 V Cascade - High Gain Mode LNA High Gain/Mixer High Gain. LNA Gain=1, Mix Gain=1. Assumes 3dB Image filter insertion loss. Gain 23.5 26 28 dB Noise Figure 2.4 dB Input IP3 -11 -9 0 dBm Current 26 mA Cascade - Mid Gain Mode LNA High Gain/Mixer Low Gain. LNA Gain=1, Mix Gain=0. Assumes 3dB Image filter insertion loss. Gain 16.5 dB Noise Figure 4.9 dB Input IP3 0 dBm Current 23 mA Cascade - Low Gain Mode LNA Low Gain/Mixer High Gain. LNA Gain=0, Mix Gain=1. Assumes 3dB Image filter insertion loss. Gain 4 dB Noise Figure 15.5 dB Input IP3 11.8 dBm Current 22 mA Cascade - Ultra-Low Gain Mode LNA Low Gain/Mixer Low Gain. LNA Gain=0, Mix Gain=0. Assumes 3dB Image filter insertion loss. Gain -7 -4.5 -3 dB Noise Figure 22.5 dB Input IP3 +14 +20 40 dBm Current 18 mA Cellular CDMA, IPSET=1 Mode LNA GAIN MIX GAIN High Gain 1 1 Recommended for IMD Tests 1 and 2 Mid Gain 1 0 Recommended for IMD Tests 3 and 4 Low Gain 0 1 Recommended for IMD Tests 5 and 6 Ultra-Low Gain 0 0 Alternative Lowest Current Mode for IMD Tests 5 and 6
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Pin Function Description Interface Schematic 1L N A G A I N Controls the bypass feature of the LNA. A logic low (<1.0V) selects the bypass mode. A logic high (>2.0V) turns on the LNA. 2 MIX GAIN Controls the bypass feature of the mixer preamp. A logic low (<1.0V) selects the bypass mode. A logic high (>2.0V) turns on the preamppreamp. 3L N A I N LNA input pin. 4V C C 1 VCC pin for all circuits except the LO. Buffer/bias circuitry. 5G N D 1 B LNA emitter. This pin provides the DC path to ground for the LNA. A lumped element or a transmission line inductor can be placed between this pin and ground to degenerate the LNA. This will decrease the gain and increase the IP3 of the LNA. As the value of inductance is increased, these effects will become more pronounced. 6L N A O U T LNA output pin. See pin 3. 7I S E T 2 An external resistor R2 connected to this pin sets the current of the preamp and the mixer. 8I S E T 1 An external resistor R3 connected to this pin sets the current of the LNA when IP SET is high (see pin 19). 9G N D 3 B Ground pin for preamp circuit. A 3.3nH inductor is used between pin 9 and ground to degenerate the mixer preamp. Degenerating the preamp will reduce the gain, increase the IP3 and affect the preamp input impedance. 10 MIX IN Mixer preamp input pin. See pin 9. 11 IF1- Second differential output pin for the first mixer. See pin 12. 12 IF1+ First differential output pin for the first mixer. Open collector. A current combiner external network performs a differential to single-ended conver- sion and sets the output impedance. A DC blocking cap must be present if the IF filter input has a DC path to ground. Mixer (IF2+ and IF-) needs to “see” a differential impedance between 2kΩ to 4kΩ. 13 BYPASS Bypass pin for the LO bias reference. 14 IF2- Second differential output pin for the second mixer. See pin 15. LNA GAIN MIX GAIN LNA IN LNA OUT GND1B MIX IN GND3B VCC2 IF1- IF1+
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Package Drawing QFN, 20-PIN, 4x4 Pin Function Description Interface Schematic 15 IF2+ First differential output pin for the second mixer. Open collector. A current combiner external network performs a differential to single-ended conver- sion and sets the output impedance. A DC blocking cap must be present if the IF filter input has a DC path to ground. Mixer (IF2+ and IF2-) needs to “see” a differential impedance between 2kΩ to 4kΩ. 16 VCC2 VCC pin for the LO buffer/bias circuitry. 17 LO IN LO limiter input pin. 18 ENABLE This pin is used to enable or disable the RF2461. A logic high (>2.0V) enables the circuitry. A logic low (<1.0V) disables the circuitry. 19 IP SET Controls the setting of the LNA current. A logic low (<1.0V) selects the internal resistance (49.5kΩ), resulting in an LNA current of 5mA. A logic high (>2.0V) selects the external resistance at pin 8. 20 IF SEL Determines which IF port is active. A logic low (<1.0V) activates IF1 and deactivates IF2. A logic high (>2.0V) activates IF2 and deactivates IF1. Mixers are identical. Either IF output may be used for CDMA or AMPS appli- cations. Pkg Base GND Ground connection. The backside of the package should be soldered to a top side ground pad which is connected to the ground plane with multiple vias. IF2- IF2+ LO IN ENABLE IP SET IF SEL Dimensions in mm. Note orientation of package. 12° MAX -C- 0.05 1.00 0.90 0.05 C 0.60
0.24 TYP
0.20
0.10 C ABM
0.65 0.30
4 PLCS
2.10 SQ. 0.23 0.13 0.50 0.75 0.50 NOTES: Shaded lead is Pin 1.1 Dimension applies to plated terminal: to be measured between 0.02 mm and 0.25 mm from terminal end.
0.15 C A
2 PLCS-A-
4.00 3.75
2 PLCS
0.15 C 4.00
0.15 C B
-B- 3.75 0.15 C
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Application Schematic 109876 20 19 18 17 16 VCC1 100 pF 33 nF16 nH 4.3 nH IF SEL 100 pF 56 Ω L2 100 pF L1 R C1 100 pF L1 R VCC1 100 pF 50 Ω μstrip 620 Ω 4 pF 100 pF0.1 μF VCC1 22 kΩ 47 kΩ 3.3 nH LNA GAIN MIX GAIN VCC2 VCC1NOTE: Microstrip Inductor, Z0 = 50 Ω, L = 102 mils suggested compared values. 51 Ω* F i l t e r 33 nF 47 nH L F i l t e r IF+ IF- L F i l t e r IF2+ IF2- LO IN LNA IN 7.5 nH 50 Ω μstrip L=130 mils W=12 mils Z0=50 Ω ENABLE IP SET *This resistor improves NF and IIP3 for VCC = 3.0 V. BYPASS See Note 4 See Note 5 See Note 3 See Note 1 See Note 6 See Note 8 See Note 8 See Note 8 See Note 8 See Note 7 See Note 2 See Note 8 See Note 10 See Note 11 See Note 9 NOTES: 1. DC blocking capacitor. 2. LNA emitter degenerator. As the value of inductance is increased, the gain will decrease, and the IIP3 will increase. 3. Mixer preamp degeneration inductor. As the value of inductance is increased, the gain will decrease, and the IIP3 will inc rease. 4. An external resistor connected to this pin sets the current of the preamp and the mixer. Higher resistance to ground resul ts in lower current. See chart at end of datasheet. 5. An external resistor connected to this pin sets the current of the LNA when IPSET is high. Higher resistance to ground res ults in lower current. See chart at end of datasheet. 6. Mixer input matching inductor. 7. LO input matching resistor. 8. Bypass capacitor. 9. LNA output matching and bias choke. 10. For stability of the LNA. 11. LNA input and output matching. 12. Low pass path to ground for two-tone beat frequency for optimum IIP3 of LNA. See Note 11 See Note 12 See Note 8 Output Interface Network
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. L1, C1, and R form a current combiner which performs a differen tial to single-ended conversion at the IF frequency and set s the output impedance. In most cases, th e resonance frequency is independent of R and can be set according to the followin g equation: Where CEQ is the equivalent stray capacitance and capac- itance looking into pins 11 and 12. An average value t o use for CEQ is 2.5pF to 3pF. R can then be used to set the output impedance according to the following equation: where ROUT is the desired output impedance and RP is the parasitic equivalent parallel resistance of L1. C1 should be chosen as high as possible (not greater than 15pF), while maintaining an R P of L1 that allows for the desired ROUT. L2 and C2 serve dual purposes. L2 serves as an outpu t bias choke, and C2 serves as a series DC block. In addition, L2 and C2 may be chosen to form an imped - ance matching network if the input impedance of the I F filter is not equal to ROUT. Otherwise, L2 is chosen to b e large, and C2 is chosen to be large if a DC path to groun d is present in the IF filter, or omitted if the filter is D C blocked. 2π L1 2 (C1 + CEQ) fIF = R = 1
4 R OUT
- 1 RP () -1
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Evaluation Board Schematic - CDMA LO@965MHz, RF@880MHz, IF@85MHz (Download Bill of Materials from www.rfmd.com.) 109876 20 19 18 17 16 VCC1 50 Ω μstrip 33 nFL2 16 nH 50 Ω μstrip 4.3 nH 50 Ω μstrip IF SEL ENABLE IP SET C16 100 pF 50 Ω μstrip 56 Ω 50 Ω μstrip 50 Ω μstrip 390 nH C15 100 pF 50 Ω μstrip C14 10 pF 50 Ω μstrip 470 nH50 Ω μstrip 10 kΩ C13 11 pF C12 11 pF C11 100 pF 50 Ω μstrip 10 pF 50 Ω μstrip 470 nH 10 kΩ 11 pF 50 Ω μstrip 50 Ω μstrip 50 Ω μstrip C10 11 pF 390 nH VCC1 100 pF 50 Ω μstrip 620 Ω 7.5 nH 4 pF 50 Ω μstrip 100 pF 0.1 μF VCC1 18 kΩ 47 kΩ 3.3 nH 50 Ω μstrip 33 nF 50 Ω μstrip 47 nH 50 Ω μstrip CON3 P1-3 LNA GAIN GND P1-1 MIX GAIN CON3 P2-3 ENABLE P2-2 IP SET P2-1 IF SEL CON3 P3-1 VCC1 GND P3-3 VCC2 VCC2 VCC1 Note: R14 improves NF and IIP3 for VCC = 3.0 V R14 51 Ω 50 Ω μstrip L=130 mils W=12 mils Z0=50 Ω LO IN 447 pS Electrical Delay 0.13 dB Line Loss LNA IN 329 pS Electrical Delay 0.10 dB Line Loss LNA GAIN MIX GAIN LNA OUT 498 pS Electrical Delay 0.15 dB Line Loss IF1 OUT 348 pS Electrical Delay @ 110 MHz 0.03 dB Line Loss MIXER IN 320 pS Electrical Delay @ 880 MHz 0.10 dB Line Loss IF2 OUT 348 pS Electrical Delay @ 110 MHz 0.03 dB Line Loss BYPASS 100 pF
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Evaluation Board Schematic - JCDMA LO@7 41MHz, RF@851MHz, IF@110MHz 109876 20 19 18 17 16 VCC1 50 Ω μstrip 33 nFL2 16 nH 50 Ω μstrip 4.3 nH 50 Ω μstrip IF SEL ENABLE IP SET C16 100 pF 50 Ω μstrip 56 Ω 50 Ω μstrip 50 Ω μstrip 270 nH C15 100 pF 50 Ω μstrip C14 7 pF 50 Ω μstrip 330 nH50 Ω μstrip 4.3 kΩ C13 9 pF C12 10 pF C11 100 pF 50 Ω μstrip 7 pF 50 Ω μstrip 330 nH 4.3 kΩ 9 pF 50 Ω μstrip 50 Ω μstrip 50 Ω μstrip C10 11 pF 270 nH VCC1 100 pF 50 Ω μstrip 620 Ω 7.5 nH 4 pF 50 Ω μstrip 100 pF 0.1 μF VCC1 18 kΩ 33 kΩ 7.5 nH 50 Ω μstrip 33 nF 50 Ω μstrip 30 nH 50 Ω μstrip CON3 P1-3 LNA GAIN GND P1-1 MIX GAIN CON3 P2-3 ENABLE P2-2 IP SET P2-1 IF SEL CON3 P3-1 VCC1 GND P3-3 VCC2 VCC2 VCC1 Note: R14 improves NF and IIP3 for VCC = 3.0 V R14 51 Ω 50 Ω μstrip L=130 mils W=12 mils Z0=50 Ω LO IN 447 pS Electrical Delay 0.13 dB Line Loss LNA IN 329 pS Electrical Delay 0.10 dB Line Loss LNA GAIN MIX GAIN LNA OUT 498 pS Electrical Delay 0.15 dB Line Loss IF1 OUT 348 pS Electrical Delay @ 110 MHz 0.03 dB Line Loss MIXER IN 320 pS Electrical Delay @ 880 MHz 0.10 dB Line Loss IF2 OUT 348 pS Electrical Delay @ 110 MHz 0.03 dB Line Loss BYPASS 100 pF
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Evaluation Board Layout Board Size 2.0" x 2.0" Board Thickness 0.031”, Board Material FR-4, Multi-Layer Assembly Top Power Plane 1 Power Plane 2
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Back
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Condition T=25 oC, VCC=2.75V, RF=880 and 881MHz, LO=965MHz @-10dBm LNA Gain, Noise Figure and IIP3 versus ICC - LNA Only (LNA High Gain) 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 ICC (mA) Gain and Noise Figure (dB) -20.0 -15.0 -10.0 -5.0 0.0 5.0 10.0 15.0 IIP3 (dBm) Gain (dB) NF (dB) IIP3 (dBm) Mixer Gain, Noise Figure and IIP3 versus ICC - Mixer (Mixer High Gain, LO=-7dBm) -20.00 -15.00 -10.00 -5.00 0.00 5.00 10.00 15.00 20.00 25.00 ICC (mA) Gain and Noise Figure (dB) -10.00 -5.00 0.00 5.00 10.00 IIP3 (dBm) Gain (dB) NF (dB) IIP3 (dBm) Resistor (R3) versus ICC (mA) - LNA Only (LNA High Gain) 0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0 180.0 200.0 ICC (mA) Resistor R3 (kΩ) R3 (kohm) Resistor (R2) versus ICC - Mixer (Mixer High Gain, LO=2170@-7dBm) 0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0 180.0 200.0 ICC (mA) Resistor R2 ( kΩ) R2 (kohm)
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.