Triple/Dual-Mode CDMA LNA/Mixers

Transcription

1 19-17; Rev 2; 4/3 EVALUATION KIT AVAILABLE Triple/Dual-Mode CDMA LNA/Mixers General Description The receiver RF front-end IC is designed for dual-band CDMA cellular phones and can also be used in dual-band TDMA, GSM, or EDGE cellular phones. Thanks to the s on-chip low-power LO divider, the cellular VCO module can be eliminated. The includes a low-noise amplifier (LNA) with an adjustable high-input third-order intercept point (IIP3) to minimize intermodulation and cross-modulation in the presence of large interfering signals. For cellular band operation, a low-gain LNA is available for higher cascaded IIP3 at lower current. The CDMA mixers are designed for high linearity, low noise, and differential IF outputs. The FM mixer is designed for lower current and single-ended output. The triple-mode LNA/mixer includes an onchip LO frequency divider to allow the use of a single VCO for both bands. This device is available in an ultrasmall 2-pin leadless QFN package. 1.4dB LNA Noise Figure db LNA Gain Mixer Noise Figure 7.5dB (CDMA).7dB (AMPS) Mixer Gain.5dB PCS.3dB Cellular.dB AMPS LO Frequency Divider, Saves VCO Module LO Output Buffers for TX Ultra-Small 2-Pin Leadless Package Features Ordering Information Applications Dual-Band, Triple-Mode PCS/Cellular Phones Dual-Mode Cellular Phones PART EGI TEMP RANGE -4 C to +5 C PIN-PACKAGE 2 QFN Pin Configuration/ Functional Diagram Typical Operating Circuit appears at end of data sheet. TOP VIEW RBIAS 2 2 IF IF BUFFEN V CC 7 FMOUT 9 11 LO/2 LOIN CLNAOUT PLNAOUT PMIXIN CMIXIN PLOOUT CLOOUT N.C. RLNA PLNAIN CLNAIN BAND LIN 2 GAIN QFN Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 ABSOLUTE MAXIMUM RATINGS V CC to...+.3v to +4.3V Digital Input Voltage to...-.3v to (V CC +.3V) LNA Input Level...1V peak LO, Mixer Input Levels...+5dBm Digital Input Current...±mA Continuous Power Dissipation (T A = +7 C) 2-Pin QFN (derate 2.5mW/ C above T A = +7 C)...2W Operating Temperature Range...-4 C to +5 C Junction Temperature...+ C Storage Temperature Range...-5 C to + C Lead Temperature (soldering, s) 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 (V CC = +2.7V to +3.3V, R RBIAS = R RLNA = 24kΩ, BUFFEN = LOW, all RF and IF outputs connected to V CC, no RF applied, T A = -4 C to +5 C. Typical values are at +3.V and T A = +25 C, unless otherwise noted. Refer to Operational Modes table for control logic.) PARAMETER CONDITIONS MIN TYP MAX UNITS PCS CDMA MODES Operating Supply Current CELLULAR CDMA MODE Operating Supply Current FM MODE High-gain, low-linearity mode 1 24 High-gain, high-linearity mode Low-gain mode High-gain, low-linearity mode 1 24 High-gain, high-linearity mode 2 35 Operating Supply Current.5 17 ma SHUTDOWN MODE Shutdown Supply Current.1 5 µa ALL MODES LO Buffer Supply Current Additional Operational Current Divider Active BUFFEN = HIGH LO/2 = LOW LO/2 = HIGH.3 Cellular and FM mode; LO/2 = HIGH 1.2 ma Digital Input Logic High 2. V Digital Input Logic Low. V Digital Input High Current 5 µa Digital Input Low Current -25 µa ma ma ma 2

3 AC ELECTRICAL CHARACTERISTICS ( EV kit, V CC = +2.7V to +3.3V, f PLNAIN = f PMIXIN = 193MHz to 199MHz, f CLNAIN = f CMIXIN = 9MHz to 94MHz, f IF = MHz, high side LO, LO/2 = LOW. All ports matched to 5Ω, R RLNA = R RBIAS = 24kΩ, T A = -4 C to +5 C. Typical values are at T A = +25 C, V CC = +3.V, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS OVERALL PERFORMANCE Low-Band RF Frequency Range 9 94 MHz High-Band RF Frequency Range MHz Low-Band LO Frequency Range After divider if active (Note 1) 95 1 MHz High-Band LO Frequency Range (Note 1) MHz IF Frequency Range (Note 1) 22 MHz LO Input Level -7-3 dbm CELLULAR LNA PERFORMANCE HIGH-GAIN, HIGH-LINEARITY MODES Gain (Note 2) db Noise Figure (Note 3) T A = +25 C db Noise Figure Change Due to Temperature T A = +25 C to T MAX.3 db IIP3 (Notes 3, 4) 9.5 dbm CDMA HIGH-GAIN, LOW-LINEARITY MODE AND FM MODE Gain (Note 2).7.5 db Noise Figure (Note 3) T A = +25 C db IIP3 (Note 3, 4) dbm CDMA LOW-GAIN MODE Gain (Note 2) dbm Noise Figure (Note 3) 5 db IIP3 (Notes 3, 4) 1 dbm PCS LNA PERFORMANCE CDMA HIGH-GAIN, HIGH-LINEARITY MODE Gain (Note 2)..3.9 db Noise Figure (Note 3) T A = +25 C db Noise Figure Change Due to Temperature T A = +25 C to T MAX.3 db IIP3 (Notes 3, 5) dbm CDMA HIGH-GAIN, LOW-LINEARITY MODE Gain (Note 2)..5.5 db Noise Figure (Note 3) T A = +25 C db IIP3 (Notes 3, 5) dbm CELLULAR MIXER PERFORMANCE CDMA HIGH-GAIN, HIGH-LINEARITY, AND LOW-GAIN MODES Gain (Note 2) db Noise Figure (Note 3) T A = +25 C db IIP3 (Note 4) dbm 3

4 AC ELECTRICAL CHARACTERISTICS (continued) ( EV kit, V CC = +2.7V to +3.3V, f PLNAIN = f PMIXIN = 193MHz to 199MHz, f CLNAIN = f CMIXIN = 9MHz to 94MHz, f IF = MHz, high side LO, LO/2 = LOW. All ports matched to 5Ω, R RLNA = R RBIAS = 24kΩ, T A = -4 C to +5 C. Typical values are at T A = +25 C, V CC = +3.V, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS HIGH-GAIN, LOW-LINEARITY IDLE MODE Gain (Note 2).1 db Noise Figure (Note 3) T A = +25 C db IIP3 (Notes 3, 4) dbm FM MODE Gain (Note 2) db Noise Figure (Note 3) T A = +25 C db IIP3 (Note 4) dbm PCS MIXER PERFORMANCE CDMA HIGH-GAIN, HIGH-LINEARITY MODE Gain (Note 2) db Noise Figure (Note 3) T A = +25 C db IIP3 (Notes 3, 5) dbm HIGH-GAIN, LOW-LINEARITY MODE Gain (Note 2) db Noise Figure (Note 3) T A = +25 C db IIP3 (Note 5) dbm ALL MODES Mixer Output 1dB Compression -1 dbm 4 x 5 Suppression (Note ) >45 db 2 x 2 Inp ut Inter cep t P oi nt ( N otes 3, 7) dbm LO Output Level (Note 3) Into 5Ω or Ω load, BUFFEN = HIGH - - dbm LO Output Leakage BUFFEN = LOW -35 dbm LO E m i ssi on at P C S LN A Inp ut P or t -55 dbm LO Emission at Cellular LNA Input Port -55 dbm LO Output Harmonic Suppression BUFFEN = HIGH - dbc LO Output Noise Power BUFFEN = HIGH PCS band, MHz below LO -1 C ell ul ar b and, 45M Hz b el ow LO -1 RF Ports Return Loss All active RF ports including 2-element matching db dbm/hz Note 1: Operation over this frequency range may require the ports to be rematched for the desired operating frequency. Note 2: MIN guaranteed by production test, MAX guaranteed by design and characterization. Note 3: Guaranteed by design and device characterization. Note 4: Two-tone IIP3. Tested at f RF1 = MHz, f RF2 =.9MHz, and power = -25dBm/tone. Note 5: Two-tone IIP3. Tested at f RF1 = 19MHz, f RF2 = MHz, and power = -25dBm/tone. Note : F LO = 4MHZ, f RF1 = 7.MHz at -3dBm, f RF2 = 1MHz at -dbm. Performance is measured as P IF due to RF1 - P IF due to RF2. Note 7: F LO = 23MHz, f RF1 = 251.5MHz at -35dBm, f RF2 = 19MHz at -dbm. Performance is measured as P IF due to RF1 - P IF due to RF2. 4

5 (T A = +25 C, unless otherwise noted.) PCS-BAND SUPPLY CURRENT 3 HGHL 25 toc CELLULAR-BAND SUPPLY CURRENT HGHL Typical Operating Characteristics toc2 17 TA = -4 C PCS-BAND HGHL LNA GAIN vs. CURRENT toc3 SUPPLY CURRENT (ma) 2 HGLL SUPPLY CURRENT (ma) 2 HGLL LGHL FM TA = +25 C TA = +5 C TEMPERATURE ( C) -5 5 TEMPERATURE ( C) 4 LNA CURRENT (ma) 1 17 CELLULAR-BAND HGHL LNA GAIN vs. CURRENT TA = -4 C TA = +25 C TA = +5 C toc4 2 5 CELLULAR-BAND LNA GAIN vs. FREQUENCY HGHL HGLL, FM toc PCS-BAND LNA GAIN vs. FREQUENCY HGLL HGHL toc LGHL LNA CURRENT (ma) FREQUENCY (MHz) FREQUENCY (MHz) 9 PCS-BAND HGHL LNA IIP3 vs. CURRENT T A = -4 C toc7 CELLULAR-BAND HGHL LNA IIP3 vs. CURRENT TA = +25 C TA = -4 C toc PCS-BAND HGHL LNA NOISE FIGURE vs. FREQUENCY toc9 IIP3 (dbm) T A = +5 C T A = +25 C IIP3 (dbm) TA = +5 C NOISE FIGURE (db) mA.4mA ma LNA CURRENT (ma) 2 4 LNA CURRENT (ma) FREQUENCY (MHz) 5

6 (T A = +25 C, unless otherwise noted.) NOISE FIGURE (db) CELLULAR-BAND HGHL LNA NOISE FIGURE vs. FREQUENCY ma 11mA ma FREQUENCY (MHz) toc CONVERSION Typical Operating Characteristics (continued) 1 CELLULAR-BAND HGHL MIXER CONVERSION GAIN vs. CURRENT T A = -4 C T A = +5 C T A = +25 C 4 MIXER CURRENT (ma) toc11 CONVERSION PCS-BAND MIXER CONVERSION GAIN vs. CURRENT T A = -4 C, HIGH-SIDE LO T A = -4 C, LOW-SIDE LO T A = +25 C, HIGH-SIDE LO T A = +25 C, LOW-SIDE LO T A = +5 C, HIGH-SIDE LO T A = +5 C, LOW-SIDE LO 4 MIXER CURRENT (µa) toc CELLULAR-BAND MIXER CONVERSION GAIN vs. LO INPUT LEVEL HGHL HGLL toc PCS-BAND MIXER CONVERSION GAIN vs. LO INPUT LEVEL HIGH-SIDE LO HGHL LOW-SIDE LO HGHL toc 11 CELLULAR-BAND MIXER CONVERSION GAIN vs. RF INPUT LEVEL toc LO INPUT LEVEL (dbm) LO INPUT LEVEL (dbm) RF INPUT LEVEL (dbm) 1 PCS-BAND MIXER CONVERSION GAIN vs. RF INPUT LEVEL HIGH-SIDE LO HGHL LOW-SIDE LO HGHL toc IIP3 (db) 4 2 CELLULAR-BAND HGHL MIXER IIP3 vs. CURRENT T A = +5 C T A = +25 C toc17 IIP3 (db) 4 2 PCS-BAND HGHL MIXER IIP3 vs. CURRENT HIGH-SIDE LO, T A = +5 C HIGH-SIDE LO, T A = +25 C toc T A = -4 C -2-4 HIGH-SIDE LO, T A = -4 C RF INPUT LEVEL (dbm) - 4 MIXER CURRENT (ma) - 4 MIXER CURRENT (ma)

7 (T A = +25 C, unless otherwise noted.) NOISE FIGURE (db) CELLULAR-BAND MIXER NOISE FIGURE vs. RF FREQUENCY FM HGLL HGHL Typical Operating Characteristics (continued) toc19 NOISE FIGURE (db) PCS-BAND MIXER NOISE FIGURE vs. RF FREQUENCY HGLL LOW-SIDE LO HGLL HIGH-SIDE LO HGHL LOW-SIDE LO HGHL HIGH-SIDE LO toc RF FREQUENCY (MHz) RF FREQUENCY (MHz) CELLULAR-BAND LO BUFFER OUTPUT LEVEL vs. INPUT LEVEL CDMA MIXER IF PORT DIFFERENTIAL PORT IMPEDANCE OUTPUT LEVEL (dbm) LO / 2 2 x LO / 2 3 x LO / 2 toc21 PARALLEL RESISTANCE (kω) CAPACITANCE RESISTANCE toc PARALLEL RESISTANCE (kω) LO INPUT LEVEL (dbm) RF FREQUENCY (MHz) 5 PARALLEL RESISTANCE (kω) FM MIXER IF PORT DIFFERENTIAL PORT IMPEDANCE RESISTANCE CAPACITANCE toc PARALLEL RESISTANCE (kω) OUTPUT LEVEL (dbm) PCS-BAND LO BUFFER OUTPUT LEVEL vs. INPUT LEVEL 2 x LO LO 3 x LO toc RF FREQUENCY (MHz) LO INPUT LEVEL (dbm) 7

8 PIN NAME FUNCTION 1 RLNA 2 PLNAIN 3,, 11, 1, 24, 25, 27, Exposed Paddle 4 CLNAIN Pin Description LNA Bias Setting Resistor Connection. For nominal bias, connect a 24kΩ resistor to ground. The value of this resistor sets the bias current for HGHL LNAs. High-Band RF Input. Requires a blocking capacitor which may be used as part of the input matching network. Ground Reference for RF, DC and Logic Inputs. Solder the exposed paddle evenly to the circuit board ground plane. Low-Band RF Input. Requires a blocking capacitor which may be used as part of the input matching network. 5 BAND Band-Select Logic Input. LOW selects high-band (PCS), HIGH selects low-band (cellular). LIN Linearity-Select Logic Input. See Detailed Description for control modes. 7 GAIN Gain-Select Logic Input. See Detailed Description for control modes. 9 LO/2 LO Divider-Select Input. LOW disables LO divider, HIGH selects divider in cellular and FM modes. See Detailed Description for control modes. LOIN LO Input Port. Requires an external DC blocking capacitor. PLOOUT PCS LO Buffer Output Port. Internally matched to Ω (nominal). Does not require a blocking capacitor. CLOOUT Cell LO Buffer Output Port. Internally matched to Ω (nominal). Does not require a blocking capacitor. The output frequency is one half LOIN when LO/2 is floating or HIGH, and equal to LOIN when LO/2 is LOW. NC No Connection FMOUT FM Mixer Output Port. Requires pullup inductor and DC blocking capacitor, which may be used as part of the output matching network. V CC Power Supply Pin. Bypass with capacitor as close to the pin as possible. 17 BUFFEN 19, 2 IF-, IF+ 21 RBIAS 22 CMIXIN 23 PMIXIN 2 PLNAOUT 2 CLNAOUT LO Output Buffer Enable. Drive BUFFEN HIGH to power up the LO output buffer associated with the selected band. Mixer Differential Outputs. Require pullup inductors and series capacitors which can be used as part of the output matching network. Bias Setting Resistor Connection. For nominal bias, connect a 24kΩ resistor to ground. The value of this resistor sets current for all blocks except HGHL LNA. Low-Band Mixer Input. Requires a blocking capacitor which may be used as part of the input matching network. High-Band Mixer Input. Requires a blocking capacitor which may be used as part of the input matching network. High-Band LNA Output Port. Connect a pullup inductor to V CC and an external series blocking capacitor which may be used as a part of the output matching network. Low-Band LNA Output Port. Connect a pullup inductor to V CC and an external series blocking capacitor which may be used as a part of the output matching network.

9 Detailed Description The consists of cellular band and PCS band (LNAs) and mixers. The IC also consists of a local oscillator (LO) divider and LO buffers for cellular and PCS bands. Low-Noise Amplifiers The LNAs gain and linearity are switched by the GAIN and LIN input, respectively. The PCS band LNA has two operational modes: high-gain high-linearity (HGHL) and high-gain low-linearity (HGLL). The cellular band LNA has three operational in modes: HGHL, HGLL, and low-gain high-linearity (LGHL) modes. The table in the Operational Modes section shows the pin settings for BAND, GAIN, and LIN for various operating modes. Use HGHL mode when extra high linearity is required for cross-modulation suppression, HGLL mode when the transmitter is off and cross-modulation is not a concern, and LGHL mode when receiving large signals. Downconverter The downconverters in these devices are double balanced mixers. The PCS band mixer and digital cellular band mixer share the same IF output ports. The cellular FM band mixer has its own IF output to feed to a different filter. When the linearity requirement is high, the LIN control input increases the current in the downconverter. The downconverter requires a DC blocking capacitor at the input and output, and a pullup inductor at the output. The DC blocking capacitors can be designed to be part of the matching circuits. The table in the Operational Modes section shows the settings for BAND, GAIN, and LIN for various operating modes. LO Output Buffers There are two LO output buffers: cellular and PCS. The inputs are tied together and internally matched to 5Ω. The outputs of the PCS and cellular buffers are brought out separately. The outputs of the buffers are internally matched and include a DC blocking capacitor. LO Divider The includes an LO divider circuit which enables a single VCO for both cellular and PCS bands. The LO/2 logic input turns the divider on or off in the cellular band. Table 1. Operational Modes FUNCTION CONTROL PIN MODES BAND (H/L) LOX1 LO /2 HGHL Amp HGLL Amp LGHL Amp CDMA HL Mixer CDMA LL Mixer FM Mixer BAND GAIN LIN LO/2 PCS Band, High-Gain, High-Linearity (HGHL) H 1 1 X PCS Band, High-Gain, Low-Linearty (Idle Mode) (HGLL) H 1 X Undefined 1 X Cellular Band CDMA, High-Gain, High-Linearity (HGHL) L Cellular Band CDMA, High-Gain, Low-Linearity (Idle Mode) (HGLL) L Cellular Band, CDMA, Low-Gain L Cellular Band, FM Mode L 1 1 Cellular Band CDMA, High-Gain, High-Linearity (HGHL) L Cellular Band CDMA, High-Gain, Low-Linearity (Idle Mode) (HGLL) L 1 1 Cellular Band, CDMA, Low-Gain L 1 1 Cellular Band, FM Mode L 1 Shutdown X 9

10 Operational Modes The various operating modes are controlled by the logic inputs BAND, GAIN, LIN, and LO/2. Table 1 shows the pin settings for the various operating modes. Applications Information Cascaded LNA/Mixer Performance The LNA and mixer design optimizes cascaded performance in all gain and linearity modes. In HGHL mode both the LNA and mixer have a low noise figure, high gain, and high linearity. The LNA has high gain to minimize the noise contribution of the mixer, thus increasing the receiver s sensitivity, and the LNA has high linearity for cross-modulation suppression. The HGLL mode is used when the transmitter is off and cross-modulation is not a concern. In LGHL mode, the received signal is strong enough that linearity is the primary concern. The LNA gain is reduced for higher system linearity. S-Parameters Use the S-parameters listed in the following tables to design the RF matching circuits. Table 2. Cellular Band LNA S-parameters High-Gain, High-Linearity Mode FREQUENCY (MHz) S11 S11 S21 S21 S S S22 S

11 Layout Considerations Keep RF signal lines as short as possible to minimize losses and radiation. Use high Q components for the LNA input-matching circuit to achieve the lowest possible noise figure. At the digital mixer outputs, keep the differential signal lines together and of equal length to ensure signal balance. For best gain and noise performance, solder the exposed paddle evenly to the board ground plane. Table 3. PCS Band LNA S-Parameters High-Gain, High-Linearity Mode FREQUENCY (MHz) S11 S11 S21 S21 S S S22 S

12 Table 4. Cellular Band Mixer Input S-Parameters High-Gain, High- Linearity Mode FREQUENCY (MHz) S11 S Table 5. PCS Band Mixer Input S-Parameters High-Gain, High-Linearity Mode FREQUENCY (MHz) S11 S

13 2.7pF.2nH V CC 2.7nH 2Ω.1µF CELL.75pF PCS 2.7nH pf Typical Operating Circuit nh 7pF PCS pf 24kΩ 2.2nH kΩ 3.3kΩ V CC nh pf nh 4pF CDMA pF pf CELLULAR 3.9nH BAND BUFFEN pf V CC LIN 2 nh.25kω 1% GAIN LO/2 22pF N.C. 4.7pF FM PCS LO LO_OUT Package Information For the latest package outline information, go to 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, San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.