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RF2498TriBand/QuadMode CDMA/GPS Low Noise Amplifier/Mixer RF2498 TRI-BAND/QUAD-MODE CDMA/GPS LOW NOISE AMPLIFIER/MIXER Package Style: QFN, 32-Pin, 5x5 GPS MIX IN 32 31 30 29 28 27 26 Features GPS Receive Front-End Gain=37dB Meets IMD Tests with Three Gain States/Two Logic Control Lines Adjustable Mixer and LNA Bias Current Selectable Divide-by-2 Prescaler Integrated TX LO Buffer Amplifier GPS+ 1 GPS LNA OUT 25 24 GPS LNA IN 23 PCS LNA IN 22 IP SET 21 PCS LNA OUT 20 CELL LNA IN 19 CELL LNA EMITTER 18 CELL LNA OUT 17 LNA GAIN 16 ENABLE BAND SEL GPS- 2 CDMA+ 3 CDMA- 4 FM+ 5 VCC2 7 LO IN 8 9 LO OUT 10 /2 SELECT 11 TX BUFF ENABLE 12 PCS RFA VCC 13 PCS MIX IN 14 CELL MIX IN 15 MIX GAIN Applications CDMA/Cellular/PCS/GPS Handsets JCDMA/GPS Handsets CDMA Modem/Data Cards Commercial and Consumer Systems Portable Battery-Powered Equipment Functional Block Diagram Product Description The RF2498 is a high performance CDMA tri-band/quad-mode integrated LNA/mixer with GPS capability. The device is designed to meet all IS-98 sensitivity, intermodulation and single-tone requirements. The RF2498 integrates the tri-band LNA/downconverters with 27.5dB of gain control for the cellular band and 29dB for the PCS band. The RF2498 is designed for three state gain control solutions for IS-98 IMD testing. The device offers a dedicated GPS LNA/mixer with 37dB of gain. Additionally, a divide-by-2 prescaler to allow the use of either a single- or dual-band VCO is integrated. There is also a TX LO buffer. The design is flexible, in that the bias currents may be set using off-chip current reference resistors for the mixer and LNA blocks. The device is packaged in a plastic, 5mmx5mm, leadless chip carrier. Ordering Information RF2498 RF2498PCBA-41X Tri-Band/Quad-Mode CDMA/GPS Low Noise Amplifier/Mixer Fully Assembled Evaluation Board Optimum Technology Matching(R) Applied GaAs HBT GaAs MESFET InGaP HBT SiGe BiCMOS Si BiCMOS SiGe HBT GaAs pHEMT Si CMOS Si BJT GaN HEMT RF MICRO DEVICES(R), RFMD(R), Optimum Technology Matching(R), Enabling Wireless ConnectivityTM, PowerStar(R), POLARISTM TOTAL RADIOTM and UltimateBlueTM are trademarks of RFMD, LLC. BLUETOOTH is a trademark owned by Bluetooth SIG, Inc., U.S.A. and licensed for use by RFMD. All other trade names, trademarks and registered trademarks are the property of their respective owners. (c)2006, RF Micro Devices, Inc. Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. /2 FM- 6 IF SEL ISET3 ISET2 ISET1 VCC1 1 of 22 RF2498 Absolute Maximum Ratings Parameter Supply Voltage Input LO and RF Levels Operating Ambient Temperature Storage Temperature Rating -0.5 to +5.0 +6 -40 to +85 -40 to +150 Unit VDC dBm C C 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 performance or functional operation of the device under Absolute Maximum Rating conditions 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 application circuitry and specifications at any time without prior notice. Parameter Overall RF Frequency Range Min. Specification Typ. 800 to 900 1500 to 2200 1575.42 Max. Unit MHz MHz MHz GPS band Condition T = 25C, VCC =2.75V IF Frequency Range 0.1 2.65 1.8 2.75 400 3.15 0.4 10 MHz V V V A ENABLE=0 Freq=869MHz to 894MHz Freq=832MHz to 870MHz LNA 50 match Power Supply Supply Voltage Logic High Logic Low Power Down Current Cellular Band JCDMA Band LNA (On) Gain Noise Figure Input IP3 Current Isolation +9.0 +5.0 13.5 13.0 15.0 14.5 1.1 1.0 +11.0 +9.0 6.5 4.5 23 -4.0 +20.0 -2.5 2.5 +25.0 0 2.5 -1.8 4.0 16.5 16.0 1.3 1.2 dB dB dB dB dBm dBm mA mA dB dB dB dBm mA dB IPSET=1 IPSET=0 IPSET=1 IPSET=0 IPSET=1 IPSET=0 IPSET=1 IPSET=0 LNA (Off) Gain Noise Figure Input IP3 Current Isolation Mixer - CDMA/JCDMA Gain Noise Figure Input IP3 +1.0 11.5 1.5 13.0 3.0 7.5 14.0 +3.5 14.5 4.5 8.5 16.0 dB dB dB dB dBm LO IN=-4dBm See note 1 and 2. Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON 2 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 +11.0 Current +13.0 18.5 13.5 dBm mA mA Mixer Preamp OFF Mixer Preamp ON/Mixer/LO Input Amps Mixer Preamp OFF/Mixer/LO Input Amps Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 3 of 22 RF2498 Parameter Mixer - CDMA/JCDMA, cont. LO to RF Isolation LO Frequency Range IF Frequency Range 36 600 0.1 183.6 2300 400 dB dB MHz MHz Min. Specification Typ. Max. Unit Condition LO IN=-4dBm See note 1 and 2. Mixer Preamp ON Mixer Preamp OFF High and Low Side LO Injection. See note 3 and 4. Typical IF frequencies: 85.38MHz, 109.80MHz, 111.85MHz, 183.6MHz LO IN=-4dBm See note 1 and 2. Mixer - FM Gain Noise Figure Input IP3 Current LO to RF Isolation LO Frequency Range IF Frequency Range 36 600 0.1 183.6 2300 400 +1.5 +11.0 11.5 1.5 13.0 3.0 7.5 14.0 +3.5 +14.0 18.5 13.5 14.5 4.5 8.5 16.0 dB dB dB dB dBm dBm mA mA dB dB MHz MHz Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON/Mixer/LO Input Amps Mixer Preamp OFF/Mixer/LO Input Amps Mixer Preamp ON Mixer Preamp OFF High and Low Side LO Injection See note 3 and 4. Typical IF frequencies: 85.38MHz, 109.80MHz, 111.85MHz, 183.6MHz Other LO-IF Isolation RF-IF Isolation LNA Out to Mixer In Isolation LO-LNA In Isolation, Any State 30 40 40 35 dB dB dB dB Freq=1930MHz to 1990MHz Freq=1840MHz to 1870MHz LNA 50 match 13.5 13.0 Noise Figure Input IP3 Current Isolation +8.0 -2.0 15.5 15.0 1.5 1.4 +12.0 +4.0 6.5 4.5 20 -6 +20.0 -4 4 +26.0 0 4 6 17.5 16.5 1.8 1.7 dB dB dB dB dBm dBm mA mA dB dB dB dBm mA dB IPSET=1 IPSET=0 IPSET=1 IPSET=0 IPSET=1 IPSET=0 IPSET=1 IPSET=0 US PCS Band Korean PCS Band LNA (On) Gain LNA (Off) Gain Noise Figure Input IP3 Current Isolation 4 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Parameter Mixer Gain Noise Figure Input IP3 Current LO to RF Isolation LO Frequency Range IF Frequency Range 36 30 1600 0.1 183.6 2400 400 +1.5 +11.0 12.0 2.5 14.0 4.5 7.0 15 +5.0 +13.0 19.0 14.0 15.5 6.5 8.5 17 dB dB dB dB dBm dBm mA mA dB dB MHz MHz Min. Specification Typ. Max. Unit LO IN=-4dBm See note 1. Condition Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON Mixer Preamp OFF Mixer Preamp ON/Mixer/LO Input Amps Mixer Preamp OFF/Mixer/LO Input Amps Mixer Preamp ON Mixer Preamp OFF High and Low Side LO Injection Typical IF frequencies: 183.6MHz, 210.38MHz, 220.38MHz Other LO-IF Isolation RF-IF Isolation LNA Out to Mixer In Isolation LO-LNA In Isolation, Any State 36 40 30 35 40 dB dB dB dB Freq=1575.42MHz LNA 50 match 17.0 16 Noise Figure Input IP3 Current Isolation +1.0 -5.0 19.0 18 1.3 1.25 +5.0 -1.0 6.5 4.5 20 1.7 1.7 dB dB dB dB dBm dBm mA mA dB LO IN=-4dBm See note 1. 16 18 5.5 7.0 Input IP3 Current LO to RF Isolation LO Frequency Range LO Input Power Range IF Frequency Range 1350 -10 0.1 -4 183.6 1800 0 400 -7.5 -5.5 15.5 dB dB dB dBm mA dB MHz dBm MHz Typical IF frequencies: 183.6MHz, 210.38MHz, 220.38MHz High and Low Side LO Injection Preamp/Mixer/LO Input Amps High Side LO Injection. Low Side LO Injection. IPSET=1 IPSET=0 IPSET=1 IPSET=0 IPSET=1 IPSET=0 IPSET=1 IPSET=0 GPS Band LNA (On) Gain Mixer Gain Noise Figure Other LO-IF Isolation RF-IF Isolation LNA Out to Mixer In Isolation LO-LNA In Isolation, Any State 36 40 30 35 40 dB dB dB dB Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 5 of 22 RF2498 Parameter Control Lines Input Capacitance 1 pF BAND SEL, IF SEL, IP SET, LNA GAIN, ENABLE, MIX GAIN, TX BUFF ENABLE, /2 SELECT Min. Specification Typ. Max. Unit Condition Local Oscillator Input Cellular - CDMA/FM/JCDMA Input Power Input Frequency PCS Input Power Input Frequency GPS Input Power Input Frequency -10 1350 -4 0 1800 dBm MHz High and Low Side LO Injection. -10 1600 -4 0 2300 dBm MHz High and Low Side LO Injection. -10 600 1200 -4 0 1078 2156 dBm MHz MHz See note 3. High and Low side injection. See note 4. High and Low side injection. TX (Local Oscillator) Buffer Cellular - CDMA/FM/JCDMA Output Power Output Frequency Output Power Output Frequency Current Consumption PCS Output Power Output Frequency Current Consumption -11 1600 2 -8 2300 dBm MHz mA Single-ended 50 load High and Low Side LO Injection -11 600 -11 1200 2 -6.5 2156 MHz mA -8 1078 dBm MHz Single-ended 50 load See note 3. High and Low Side LO Injection. Single-ended 50 load See note 4. High and Low Side LO Injection. NOTE 1. Mixer performance can be changed with external IF load/tuning. NOTE 2. Specifications apply for conditions of LO Divider enabled or disabled. NOTE 3. LO Divider disabled. LO Divider disabled logic conditions: A) BAND SELECT=1; /2 SELECT=Immaterial.B) BAND SELECT=0; /2 SELECT=1 NOTE 4. LO Divider enabled. LO Divider enabled logic conditions: A) BAND SELECT=0; /2 SELECT=0 6 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Evaluation Board Current Measurement BAND SEL CDMA CellularHigh IIP3 LNA Mode* LNA On, Mixer Preamp On, TX Buffer Off, /2 Off LNA On, Mixer Preamp Off, TX Buffer Off, /2 Off LNA Bypassed, Mixer Preamp On, TX Buffer Off, /2 Off LNA Bypassed, Mixer Preamp Off, TX Buffer Off, /2 Off FM/JCDMALow Current LNA Mode LNA On, Mixer Preamp On, TX Buffer Off, /2 Off LNA On, Mixer Preamp Off, TX Buffer Off, /2 Off LNA Bypassed, Mixer Preamp On, TX Buffer Off, /2 Off LNA Bypassed, Mixer Preamp Off, TX Buffer Off, /2 Off CDMA PCS High IIP3 LNA Mode* LNA On, Mixer Preamp On TX Buffer Off, /2 Off* LNA On, Mixer Preamp Off TX Buffer Off, /2 Off* LNA Bypassed, Mixer Preamp On TX Buffer Off, /2 Off LNA Bypassed, Mixer Preamp Off TX Buffer Off, /2 Off GPS LNA On, Mixer On 1 0 1 X X 0 0 X 24.0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 0 1 0 1 1 X X 0 0 0 0 1 1 1 1 27.5 25.5 21.0 16.0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 0 0 1 0 1 0 0 0 X X 0 0 0 0 1 1 1 1 25.0 20.0 20.5 15.5 0 0 0 0 1 1 1 1 1 1 1 1 1 1 0 0 1 0 1 0 1 1 X X 0 0 0 0 1 1 1 1 27.0 22.0 20.5 15.5 IF SEL ENABLE LNA GAIN MIX GAIN IP SET TX BUFF ENABLE /2 SELECT IDC (mA) NOTES: All IDC current numbers include bias circuitry current of 1.5mA to 2.0mA (dependent on mode). TX Buffer On: Add 2mA to total current. /2 Select On: Add 2mA to total current. "X" denotes setting does not impact current. *For Paging mode set IPSET=0. Total current reduced 2mA. Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 7 of 22 RF2498 Cascaded Performance (Typical Values for VCC =2.75V) NOTE: All total current numbers include bias circuitry current of 1.5mA to 2.0mA (dependent on mode). CELL CDMA LNA ON Parameter Mixer Preamp On Cascaded: Gain (dB) Noise Figure (dB) Input IP3 (dBm) LO to IF Isolation (dB) IF1 to RF Isolation (dB) IF2 to RF Isolation (dB) LO to LNA IN Isolation (dB) Total Current (mA) 25.0 2.1 -8.5 30 40 40 45 *27.0 7.5 13.0 +8.9 30 40 40 45 20.5 15.0 4.5 +0.6 30 40 40 45 *22.0 -2.5 19.5 +17.6 30 40 40 45 15.5 LNA OFF LNA ON LNA OFF LNA at Max IIP3, IPSET=1 Mixer Preamp Off NOTE: Assumes 3dB image filter insertion loss. The TX Buffer Enable is off. Div/2 function is off. Numbers represent high linearity LNA bias setting IPSET=1. *For Paging mode set IPSET=0. Total current reduced 2mA. FM/JCDMA Parameter Cascaded: Gain (dB) Noise Figure (dB) Input IP3 (dBm) LO to IF Isolation (dB) IF1 to RF Isolation (dB) IF2 to RF Isolation (dB) LO to LNA IN Isolation (dB) Total Current (mA) 24.5 2.1 -8.1 30 40 40 45 25.0 7.5 13.0 +8.9 30 40 40 45 20.5 14.5 4.8 +1.6 30 40 40 45 20.0 -2.5 19.5 +18.4 30 40 40 45 15.5 LNA ON LNA OFF LNA ON LNA OFF Mixer Preamp On Mixer Preamp Off NOTE: Assumes 3dB image filter insertion loss. The TX Buffer Enable is off. Div/2 function is off. Numbers represent low current LNA bias setting IPSET=0. 8 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 PCS CDMA LNA ON Parameter Cascaded: Gain (dB) Noise Figure (dB) Input IP3 (dBm) LO to IF Isolation (dB) IF1 to RF Isolation (dB) IF2 to RF Isolation (dB) LO to LNA IN Isolation (dB) Total Current (mA) 26.5 2.2 -7.5 40 40 40 40 *27.5 7 14 +11.8 40 40 40 40 21.0 17.0 5.0 +0.2 40 40 40 40 *22.5 -2.5 22 +19.0 40 40 40 40 16.0 LNA OFF LNA ON LNA OFF LNA at Max IIP3, IPSET=1 Mixer Preamp ON Mixer Preamp OFF NOTE: Assumes 3dB image filter insertion loss. The TX Buffer Enable is off. Div/2 function is off. Numbers represent high linearity LNA bias setting IPSET=1. *For Paging mode set IPSET=0. Total current reduced 2mA. Cascaded Performance (Typical Values for VCC =2.75V) NOTE: All total current numbers include bias circuitry current of 1.5mA to 2.0mA (dependent on mode). Parameter Cascaded: Gain (dB) Noise Figure (dB) Input IP3 (dBm) Total Current (mA) 35.5 1.6 -23.0 24 GPS High IIP3 LNA Mode, IPSET=1 IPSET=0 34.5 1.6 -22.0 22 NOTE: Assumes 1.5dB image filter insertion loss. The TX Buffer Enable is off. /2 Select is off. Cellular CDMA Gain Control Mode LNA GAIN MIX GAIN High Gain Mid Gain Low Gain Ultra Low Gain 1 1 0 0 1 0 1 0 IMD Test 1 and 2 IMD Test 3 and 4 Comments IMD Test 5 and 6 option 1 IMD test 5 and 6 option 2 Note: Contact RFMD for Application note on gain control PCBA layout and software recommendations. Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 9 of 22 RF2498 Pin 1 Function GPS+ Type Description AO GPS IF output. Open collector. Interface Schematic GPS+ GPS- 2 3 GPSCDMA+ AO AO GPS IF output. Open collector. CDMA IF output. Open collector. See pin 1. CDMA+ CDMA- 4 5 CDMAFM+ AO AO CDMA IF output. Open collector. FM IF output. Open collector. "Current combiner" IF interface to SAW filter recommended. (See "IF Output Matching Network" section.) See pin 3. FM+ FM- 6 7 8 FMVCC2 LO IN AO P AI FM IF output. Open collector. "Current combiner" IF interface to See pin 5. SAW filter recommended. (See "IF Output Matching Network" section.) VCC connection for internal LO amplifiers. Internal RF bypass capacitor. External bypass capacitor between 1nF and 47nF required. LO single-end input. Matched to 50. LO IN 70 9 10 LO OUT /2 SELECT AO DI LO output. Internal DC block. Logic input. Low enables /2 circuitry in cellular mode. The divider is disabled when BAND SEL (pin 27) is high, regardless of the state of pin 10. The divider can only be enabled when BAND SEL is low and pin10 is low. Pin 10 can be tied to a low state allowing BANDSEL (pin 27) to control the LO divider function, if using a single LO input source. Logic input. High enables TX LO output buffer amplifiers. See pin 11. 11 TX BUFF ENABLE PCS RFA VCC PCS MIX IN DI TX BUF 12 13 P AI VCC connection for PCS mixer preamplifier. PCS mixer RF single-end input. PCS MIX IN 14 CELL MIX IN AI Cellular mixer RF single-end input. Matched to 50. CELL MIX IN 10 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Pin 15 Function MIX GAIN Type Description Interface Schematic Logic input. Logic high turns on PCS or cellular mixer preamp and DI provides maximum gain. Logic low will bypass the PCS and cellular mixer preamp. MIX GAIN 16 ENABLE DI Logic input. Low level powers down the IC. ENABLE 17 LNA GAIN DI Logic input. High activates cellular or PCS LNAs. Low selects LNA bypass mode for both bands. LNA GAIN 18 19 20 CELL LNA OUT CELL LNA EMITTER CELL LNA IN AO AO AI Cellular LNA output. Simple external L-C components required for matching and VCC supply. Cellular LNA emitter. A small inductor connects this pin to ground. Cellular LNA gain can be adjusted by the inductance. Cellular LNA input. See pin 20. See pin 20. VCC CELL LNA OUT CELL LNA IN CELL LNA EMITTER 21 PCS LNA OUT AO PCS LNA output. Simple external L-C components required for matching and VCC supply. PCS LNA IN VCC PCS LNA OUT 22 IP SET DI Logic input. High selects high IIP3 LNA "boost" modes for GPS, cellular and PCS CDMA paths. Low selects "normal" LNA IIP3 mode for GPS, cellular and PCS CDMA paths. Bias setting resistor at pin 31 allows for the adjustment of LNA IIP3 in boost mode. PCS LNA input. For best performance, simple external matching required. GPS LNA input. For best performance, simple external matching required. IP SET 23 24 PCS LNA IN GPS LNA IN AI AI See pin 21. VCC GPS LNA OUT GPS LNA IN 25 26 GPS LNA OUT IF SEL AO DI GPS LNA output. Simple external L-C components required for matching and VCC supply. Logic input. High selects CDMA IF outputs; low selects FM or GPS IF outputs. See pin 24. IF SEL 27 BAND SEL DI Logic input. High level selects PCS or GPS band; low level selects cellular band. The LO divider circuitry is disabled when BAND SEL is high, regardless of the state of pin 10 (/2 SELECT). When BAND SEL is low, pin 10 can be selected high or low. If using a single LO input, pin 10 can be tied to a low state allowing BAND SEL to control the LO divider function. BAND SEL Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 11 of 22 RF2498 Pin 28 Function GPS MIX IN Type Description AI GPS mixer RF single-end input. Interface Schematic GPS MIX IN 29 VCC1 P 30 31 32 Pkg Base Legend: ISET1 ISET2 ISET3 GND AO AO AO P DC supply for internal reference, logic control, cellular mixer preamp, and GPS mixer preamp (PCS mixer preamp has its' own DC supply, PCS_RFA_VCC). External bypass capacitor between 1nF and 47nF required. Resistor for internal voltage reference setting. Recommended value 5.1k. Resistor to ground sets the LNA current in boost mode (all three LNAs). Higher resistance results in lower current. Resistor to ground sets preamp and mixer currents in all bands. Higher resistance results in lower currents. 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. DI=Digital Input from Baseband Chip AI=Analog Input AO=Analog Output P=VCC or GND ISET Pins ISET1 sets the internal reference voltage for the bias control circuits to all functional blocks. An external resistor of 5.1k to ground is required. We do not recommend adjusting this resistor value. This resistor is pulled out to allow for a higher precision off chip value and not as a significant tuning adjustment. ISET2 sets the DC current through the LNAs in all bands when IPSET is high. Higher resistance to ground results in lower current through the LNA. Increasing the LNA current will improve the IIP3 of the LNA and slightly increase gain in all modes. NF typically will get worse as you increase current. Increasing the LNA current in one mode, i.e. Cellular, will also increase the LNA current for the high IPSET state for PCS and the GPS LNAs as well. ISET3 sets the DC current through the mixer and mixer preamplifier for all bands. Higher resistance to ground results in lower current. Lower current will improve mixer NF but will degrade IIP3. Mixer and the mixer preamp gain is not significantly changed with current. 12 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Package Drawing Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 13 of 22 RF2498 Application Schematic VCC BAND SEL IF SEL 4 GND 5 1 GND IN GND 2 OUT GND 6 33 nH 3 See Note 13 GPS RF Saw 15 See Note 11 6.8 nH See Note 14 TBD GPS IF VCC TBD 33 nF See Note 4 VCC 18 nH See Notes 12 and 15 See Note 10 See Note 1 See Note 2 See Note 3 1.0 pF 5.1 k GPS LNA IN See Note 4 7.5 k TBD TBD TBD 20 k 32 1 TBD VCC 10 9 4 5 31 30 29 28 27 26 25 24 2.7 nH See Notes 14 and 15 See Notes 7 and 15 See Note 10 33 nF 33 nH 1.2 nH 0.75 pF PCS LNA IN 2 TBD TBD TBD 23 33 nF See Note 4 See Notes 14 and 15 CDMA+ CDMA- TBD CDMA IF SAW 3 22 4.7 nH See Notes 12 and 15 IP SET See Note 11 TBD TBD 4 21 10 VCC 5 TBD VCC 10 9 4 5 20 See Notes 14 and 15 2.7 nH CELL LNA IN FM+ FM- TBD TBD TBD TBD 7 /2 6 19 1.2 nH 18 See Notes 6 and 15 See Note 4 33 nF 33 nH See Notes 7 and 15 FM IF SAW 8 9 10 11 12 13 14 15 16 17 10 nH VCC VCC See Notes 12 and 15 LNA GAIN ENABLE LO IN 2.2 nH LO OUT DIV EN TX BUF EN 3.3 nH 6 3 OUT See Note 14 MIX GAIN See Note 4 33 nF VCC 1.2 pF 5 GND GND GND GND 4 1 200 VCC See Note 9 2 IN See Note 8 Cell RF Saw 2.4 pF See Note 14 See Note 4 6 3 OUT TBD TBD 1 pF 33 nF 5 GND GND GND GND 4 1 2 See Note 8 PCS RF Saw IN 33 nF See Note 4 Note: If any functional blocks are not being used, the unused pins can be left with no connection. Layout Note: To minimize losses and radiation, the RF signal traces should be as short as possible. The IF+ and IF- outputs traces should be symmetrical. All bypass capacitors and matching capacitors must have a ground via very close to the capacitor. Each capacitor should have its own ground via. All traces should be 50 transmission lines. Position inductors to reduce coupling (see note 15). NOTES: 1. This resistor sets mixer preamp and mixer currents in all bands. Lowering the resistance results in higher currents. 2. This resistor sets LNA currents of all bands in boost mode. Increasing the resistor value results in lower currents. 3. Sets internal bias voltage. Recommend 5.1 k. 4. DC blocking capacitor. 5. PCS LNA Input Matching. Optimize for NF. 6. Determines trade off between IIP3 and Gain. Higher value inductor means lower gain and higher IIP3. 7. Cell/PCS LNA Input Matching for optimum IIP3. Low impedance path to ground at low frequency for optimum IIP3. 8. For cell and PCS mixer input matching. 9. PCS Interstage matching. As the value of the inductance is increased, the PCS mixer preamp gain will decrease and the IIP3 will increase and vice versa. 10. For optimum NF and input matching. As the value of the capacitance is increased, the NF will become worse. 11. To optimize performance over temperature and bias. 12. For output matching and a DC supply bias choke. 13. GPS mixer input matching for optimum IIP3. Low impedance path to ground at low frequency for optimum IIP3. 14. Input or Output matching. 15. Coupling of coils on the input, output, and emitter (where applicable) of any LNA should be minimized to reduce the risk of oscillation. We recommend separating the inductors and/or positioning them 90 o relative to each other. NOTE: IF output matching component values are dependent on board layout, IF SAW filter and the IF frequency selected. Please contact RFMD application engineering for assistance with IF output matching. 14 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Evaluation Board Schematic GND 5 GND L13 33 nH C42 33 nF C40 33 nF C41 DNI FL6 2 50 strip J14 GPS MIX IN 4 OUT GND GND 3 1 IN GPS RF Saw J1 GPS IF 50 strip C4 6.8 pF C21 VCC 100 pF L4 180 nH BAND SEL L10 120 nH R1 5.6 k C34 DNI C27 6.8 pF R5 7.5 k R4 20 k R6 5.1 k C43 33 nF VCC IF SEL 6 C48 DNI L19 6.8 nH L20 18 nH C50 33 nF R8 10 C24 100 pF VCC L5 33 nF 50 strip J13 GPS LNA OUT J2 CDMA IF 50 strip C2 33 nF C6 5.1 pF C17 DNI L6 180 nH C39 6.8 pF C32 2.7 nH L23 DNI C19 1.0 pF 50 strip J12 GPS LNA IN 32 C12 DNI C10 DNI L2 DNI C11 FL2 10 DNI 9 4 5 31 30 29 28 27 26 25 24 C62 33 nF L26 DNI C22 100 pF C31 DNI VCC 1 CDMA IF SAW L7 DNI L11 120 nH R2 10 k C35 DNI C28 6.8 pF 2 23 R11 1.2 nH L25 33 nH C70 0.75 pF VCC 50 strip J11 PCS LNA IN 3 C37 6.8 pF 22 IP SET 4 21 J3 FM IF 50 strip C3 33 nF 10 4 5 C5 6.2 pF C18 DNI L14 DNI C30 DNI C23 100 pF VCC L8 150 nH L12 120 nH R3 24 k C36 DNI C38 6.8 pF L9 DNI C44 33 nF C29 6.8 pF C64 33 nF L16 33 nH L24 1.2 nH L22 4.7 nH L27 2.7 nH R9 10 C63 33 nF C26 100 pF 50 strip J10 PCS LNA OUT J9 CELL LNA IN 5 20 FL3 /2 6 19 50 strip C15 DNI C13 DNI L3 DNI C14 DNI 9 7 18 IF SAW 8 9 10 11 12 13 14 15 16 17 L21 10 nH ENABLE MIX GAIN LNA GAIN C69 2.4 pF 2498310, Rev. 1 C25 100 pF VCC VCC J4 LO IN J5 LO OUT 50 strip R7 DNI 50 strip C1 DNI L17 2.2 nH 50 strip J8 CELL LNA OUT DIV EN TX BUF EN C8 33 nF C61 33 nF L15 1.2 pF R10 0 C9 33 nF C56 DNI 5 6 3 OUT FL4 GND GND 4 1 GND GND R12 200 C33 33 nF J6 PCS MIX IN 50 strip L18 3.3 nH VCC C59 DNI 5 2 Cell RF Saw C58 DNI 50 strip IN J7 CELL MIX IN FL5 GND OUT GND GND GND C66 DNI 4 1 3 IN 2 *IF FREQ = 184 MHz P1-1 C45 33 nF P1-2 C51 33 nF P1-3 C52 33 nF P1-4 C49 33 nF P1 1 2 3 4 CON4 P2-4 C55 33 nF DIV EN IF SEL IP SET BAND SEL P2-3 C53 33 nF P2-2 C46 33 nF P2-1 C54 33 nF P2 1 2 3 4 CON4 ENABLE TX BUF EN MIX GAIN LNA GAIN C7 33 nF C16 1 pF 6 PCS RF SAW P3 P3-1 C20 1 F 1 2 3 CON3 VCC GND GND Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 15 of 22 RF2498 Evaluation Board Layout Board Size 3.0" x 3.0" Board Thickness 0.064", Board Material FR-4, Multi-Layer 16 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 17 of 22 RF2498 18 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 19 of 22 RF2498 Cellular Band LO Output Power versus LO Input Power -6.0 Cellular Band LO Output Power versus VCC -6.00 (Freq=2128MHz, Divider=0(ON), VCC 2.75V, Temp 25 C) o (Freq=2128MHz, Divider=0 (on), Input Power-4dBm, Temp 25 C) o LB-LO Output Power (dBm) LB-LO Output Power (dBm) -6.5 -6.50 -7.0 -7.00 -7.5 -7.50 -8.0 -10.0 -8.0 -6.0 -4.0 -2.0 0.0 -8.00 2.70 2.75 2.80 2.85 2.90 2.95 3.00 3.05 3.10 3.15 LO Input Power (dBm) VCC (V) Cellular Band LO Output Power versus LO-Input Power -6.0 Cellular Band LO Output Power versus VCC -6.00 (Freq=1064MHz, Divider 1(off), VCC=2.75V, Temp 25 C) o (Freq=1064MHz, Divider=1(off), Input Power-4dBm, Temp 25 C) o -6.5 LB-LO Output Power (dBm) -7.5 LB-LO Output Power (dBm) -7.0 -7.00 -8.0 -8.00 -8.5 -9.0 -9.00 -9.5 -10.0 -10.0 -8.0 -6.0 -4.0 -2.0 0.0 -10.00 2.70 2.75 2.80 2.85 2.90 2.95 3.00 3.05 3.10 3.15 LO-Input Power (dBm) VCC (V) -6.0 PCS Band LO Output Power versus LO-Input Power (Freq=2144MHz, VCC 2.75V, Temp 25oC) PCS Band LO Output Power versus VCC -6.00 (Freq=2144MHz, Input Power -4dBm, Temp 25 C) o -6.50 HB-LO Output Power (dBm) HB-LO Output Power (dBm) -7.0 -7.00 -7.50 -8.0 -8.00 -8.50 -9.0 -9.00 -9.50 -10.0 -10.0 -8.0 -6.0 -4.0 -2.0 0.0 -10.00 2.70 2.75 2.80 2.85 2.90 2.95 3.00 3.05 3.10 3.15 LO-Input Power (dBm) VCC (V) 20 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 RF2498 PCB Design Requirements PCB Surface Finish The PCB surface finish used for RFMD's qualification process is electroless nickel, immersion gold. Typical thickness is 3inch to 8inch gold over 180inch nickel. PCB Land Pattern Recommendation PCB land patterns are based on IPC-SM-782 standards when possible. The pad pattern shown has been developed and tested for optimized assembly at RFMD; however, it may require some modifications to address company specific assembly processes. The PCB land pattern has been developed to accommodate lead and package tolerances. PCB Metal Land Pattern A = 0.64 x 0.28 (mm) Typ. B = 0.28 x 0.64 (mm) Typ. C = 3.50 (mm) Sq. 3.50 Typ. 0.50 Typ. Pin 32 Pin 1 Dimensions in mm. B A A A A A A A A B B B B B B B B A A A Pin 24 0.50 Typ. 1.75 Typ. 3.50 Typ. C A A A A A 0.55 Typ. 0.55 Typ. B B B B B B B Pin 16 1.75 Typ. Figure 1. PCB Metal Land Pattern (Top View) Rev A3 DS030711 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. 21 of 22 RF2498 PCB Solder Mask Pattern Liquid Photo-Imageable (LPI) solder mask is recommended. The solder mask footprint will match what is shown for the PCB metal land pattern with a 2mil to 3mil expansion to accommodate solder mask registration clearance around all pads. The center-grounding pad shall also have a solder mask clearance. Expansion of the pads to create solder mask clearance can be provided in the master data or requested from the PCB fabrication supplier. A = 0.74 x 0.38 (mm) Typ. B = 0.38 x 0.74 (mm) Typ. C = 3.60 (mm) Sq. 3.50 Typ. 0.50 Typ. Pin 32 Pin 1 Dimensions in mm. BBBBBBBB A A A A A A A A BBBBBBBB C A A A A A A A A Pin 24 0.50 Typ. 1.75 Typ. 3.50 Typ. 0.55 Typ. 0.55 Typ. 1.75 Typ. Pin 16 Figure 2. PCB Solder Mask Pattern (Top View) 22 of 22 7628 Thorndike Road, Greensboro, NC 27409-9421 * For sales or technical support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com. Rev A3 DS030711 |
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