MAX2411A Low-Cost RF Up/Downconverter with LNA And

19-1324; Rev 1; 2/98

EVALUATION KIT AVAILABLE Low-Cost RF Up/Downconverter with LNA and PA Driver

______General Description ______Features MAX2411A The MAX2411A performs the RF front-end transmit/ ♦ Low-Cost Silicon Bipolar Design receive function in time-division-duplex (TDD) communi- ♦ Integrated Upconvert/Downconvert Function cation systems. It operates over a wide frequency range and is optimized for RF frequencies around 1.9GHz. ♦ Operates from a Single +2.7V to +5.5V Supply Applications include most popular cordless and PCS ♦ 3.2dB Combined Receiver Noise Figure: standards. The MAX2411A includes a low-noise amplifier 2.4dB (LNA) (LNA), a downconverter mixer, a local-oscillator buffer, an 9.2dB (mixer) upconverter mixer, and a variable-gain power-amplifier ♦ (PA) driver in a low-cost, plastic surface-mount package. Flexible Power-Amplifier Driver: The MAX2411A’s unique bidirectional, differential IF port 18dBm Output Third-Order Intercept (OIP3) reduces cost and component count by allowing the trans- 35dB Gain-Control Range mit and receive paths to share the same IF filter. ♦ LO Buffer for Low LO Drive Level The LNA has a 2.4dB typical noise figure and a -10dBm ♦ Low Power Consumption: input third-order intercept point (IP3). The downconvert- 60mW Receive er mixer has a low 9.2dB noise figure and 4dBm input 90mW Full-Power Transmit IP3. Image and local-oscillator filtering are implemented off-chip for maximum flexibility. The PA driver amplifier ♦ 0.3µW Shutdown Mode has 15dB of gain, which can be reduced over a 35dB ♦ Flexible Power-Down Modes Compatible with range. Power consumption is only 60mW in receive MAX2510/MAX2511 IF Transceivers mode and 90mW in transmit mode and drops to less than 3µW in shutdown mode. ______Ordering Information For applications requiring separate, single-ended IF input and output ports, refer to the MAX2410 data PART TEMP. RANGE PIN-PACKAGE sheet. For applications requiring only a receive func- MAX2411AEEI -40°C to +85°C 28 QSOP tion, Maxim offers a low-cost downconverter with LNA MAX2411AE/D -40°C to +85°C Dice* (see the MAX2406 data sheet). *Dice are specified at TA = 25°C, DC parameters only. ______Applications PWT1900 DECT Pin Configuration DCS1800/PCS1900 ISM-Band Transceivers TOP VIEW PHS/PACS Iridium Handsets GND 1 28 GND

LNAIN 2 27 LNAOUT Typical Operating Circuit appears on last page. GND 3 26 GND MAX2411A Functional Diagram GND 4 25 GND

VCC 5 24 RXMXIN LNAOUT RXMXIN RXEN 6 23 GND

RX MIXER LO 7 22 IF LNAIN LNA LO 8 21 IF

IF TXEN 9 20 GND RXEN POWER IF V 10 19 TXMXOUT TXEN MANAGEMENT MAX2411A LO CC LO GC 11 18 GND PA DRIVER PADROUT GND 12 17 GND

TX MIXER PADROUT 13 16 PADRIN

GND 14 15 GND GC PADRIN TXMXOUT QSOP

______Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 408-737-7600 ext. 3468. Low-Cost RF Up/Downconverter with LNA and PA Driver

ABSOLUTE MAXIMUM RATINGS VCC to GND ...... -0.3V to 6V Continuous Power Dissipation (TA = +70°C) LNAIN Input Power ...... 15dBm QSOP (derate 11mW/°C above +70°C)...... 909mW LO, LO Input Power ...... 10dBm Junction Temperature...... +150°C PADRIN Input Power...... 10dBm Operating Temperature Range ...... -40°C to +85°C RXMXIN Input Power ...... 10dBm Storage Temperature...... -65°C to +165°C IF, IF Input Power (transmit mode) ...... 10dBm Lead Temperature (soldering, 10sec) ...... +300°C Voltage at RXEN, TXEN, GC...... -0.3V to (VCC + 0.3V) 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. MAX2411A DC ELECTRICAL CHARACTERISTICS (VCC = +2.7V to +5.5V, VGC = +3.0V, RXEN = TXEN = 0.6V, PADROUT pulled up to VCC with 50Ω resistor; IF, IF pulled up to VCC with 50Ω resistor, TXMXOUT pulled up to VCC with 125Ω resistor, LNAOUT pulled up to VCC with 100Ω resistor, all RF inputs open, TA = -40°C to +85°C. Typical values are at +25°C and VCC = +3.0V, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS Supply-Voltage Range 2.7 5.5 V Digital Input Voltage High RXEN, TXEN pins 2.0 V Digital Input Voltage Low RXEN, TXEN pins 0.6 V RXEN Input Bias Current (Note 1) RXEN = 2.0V 0.1 1 µA TXEN Input Bias Current (Note 1) TXEN = 2.0V 0.1 1 µA GC Input Bias Current GC = 3V, TXEN = 2V 35 51.1 µA Supply Current, Receive Mode RXEN = 2.0V 20 29.6 mA Supply Current, Transmit Mode TXEN = 2.0V 30 44.7 mA Supply Current, Standby Mode RXEN = 2.0V, TXEN = 2.0V 160 520 µA Supply Current, Shutdown Mode VCC = 3.0V 0.1 10 µA AC ELECTRICAL CHARACTERISTICS (MAX2411A EV kit, VCC = +3.0V, VGC = +2.15V, RXEN = TXEN = low, all measurements performed in 50Ω environment, fLO = 1.5GHz, PLO = -10dBm, fLNAIN = fPADRIN = fRXMXIN = 1.9GHz, PLNAIN = -32dBm, PPADRIN = PRXMXIN = -22dBm, fIF, IF = 400MHz, PIF = -32dBm (Note 1), TA = +25°C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS LOW-NOISE AMPLIFIER (RXEN = high) TA = +25°C 14.2 16.2 17.4 Gain (Note 2) dB TA = TMIN to TMAX 12.6 19.1 Noise Figure 2.4 dB Input IP3 (Note 3) -10 dBm Output 1dB Compression -5 dBm LO to LNAIN Leakage RXEN = high or low -49 dBm RECEIVE MIXER (RXEN = high) TA = +25°C 8.5 9.4 10.0 Conversion Gain (Note 2) dB TA = -40°C to +85°C 7.5 10.9 Noise Figure Single sideband 9.2 dB Input IP3 (Note 4) 4.0 dBm Input 1dB Compression -7.7 dBm IF Frequency (Notes 2, 5) 450 MHz Minimum LO Drive Level (Note 6) -17 dBm

2 ______Low-Cost RF Up/Downconverter with LNA and PA Driver

AC ELECTRICAL CHARACTERISTICS (continued) MAX2411A (MAX2411A EV kit, VCC = +3.0V, VGC = +2.15V, RXEN = TXEN = low, all measurements performed in 50Ω environment, fLO = 1.5GHz, PLO = -10dBm, fLNAIN = fPADRIN = fRXMXIN = 1.9GHz, PLNAIN = -32dBm, PPADRIN = PRXMXIN = -22dBm, fIF, IF = 400MHz, PIF = -32dBm (Note 1), all impedance measurements made directly to pin (no matching network), TA = +25°C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS TRANSMIT MIXER (TXEN = high) TA = +25°C 6.8 8.5 9.3 Conversion Gain (Note 1) dB TA = TMIN to TMAX 5.7 10.4 Output IP3 (Notes 1, 7) 0.5 dBm Output 1dB Compression Point -11.1 dBm LO Leakage -58 dBm Noise Figure Single sideband 8.3 dB IF Frequency (Notes 2, 5) 450 MHz FOUT = 2LO-2IF = 2.2GHz -45.5 Intermod Spurious Response F = 2LO-3IF = 1.8GHz -70 dBc (Note 8) OUT FOUT = 3LO-6IF = 2.1GHz -90 PA DRIVER (TXEN = high) TA = +25°C 13 15 16.4 Gain (Note 2) dB TA = TMIN to TMAX 12.3 17 Output IP3 (Note 4) 18 dBm Output 1dB Compression Point 6.3 dBm Gain-Control Range 35 dB Gain-Control Sensitivity (Note 9) 12 dB/V LOCAL-OSCILLATOR INPUTS (RXEN = TXEN = high) Receive mode (TXEN = low) 1.10 Input Relative VSWR Transmit mode (RXEN = low) 1.02 POWER MANAGEMENT (RXEN = TXEN = low) Receiver Turn-On Time (Notes 2, 10) RXEN = low to high 0.5 2.5 µs Transmitter Turn-On Time (Notes 2, 11) TXEN = low to high 0.3 2.5 µs

Note 1: Power delivered to IF SMA connector of MAX2411A EV kit. Power delivered to MAX2411A IC is approximately 1.0dB less due to balun losses. Note 2: Guaranteed by design and characterization. Note 3: Two tones at 1.9GHz and 1.901GHz at -32dBm per tone. Note 4: Two tones at 1.9GHz and 1.901GHz at -22dBm per tone. Note 5: Mixer operation guaranteed to this frequency. For optimum gain, adjust output match. See the Typical Operating Characteristics for graphs of IF port impedance versus IF frequency. Note 6: At this LO drive level, the mixer conversion gain is typically 1dB lower than with -10dBm LO drive. Note 7: Two tones at 400MHz and 401MHz at -32dBm per tone. Note 8: Transmit mixer output at -17dBm. Note 9: Calculated from measurements taken at VGC = 1.0V and VGC = 1.5V. Note 10: Time from RXEN = low to RXEN = high transition until the combined receive gain is within 1dB of its final value. Measured with 47pF blocking capacitors on LNAIN and LNAOUT. Note 11: Time from TXEN = low to TXEN = high transition until the combined transmit gain is within 1dB of its final value. Measured with 47pF blocking capacitors on PADRIN and PADROUT.

______3 Low-Cost RF Up/Downconverter with LNA and PA Driver

______Typical Operating Characteristics (MAX2411A EV kit, VCC = +3.0V, VGC = +2.15V, RXEN = TXEN = low, all measurements performed in 50Ω environment, fLO = 1.5GHz, PLO = -10dBm, fLNAIN = fPADRIN = fRXMXIN = 1.9GHz, PLNAIN = -32dBm, PPADRIN = PRXMXIN = -22dBm, fIF, IF = 400MHz, PIF = -32dBm (Note 1), all impedance measurements made directly to pin (no matching network), TA = +25°C, unless otherwise noted.)

TRANSMIT-MODE SUPPLY CURRENT RECEIVE-MODE SUPPLY CURRENT SHUTDOWN SUPPLY CURRENT vs. TEMPERATURE vs. TEMPERATURE vs. TEMPERATURE 38 24 0.10 TXEN = V RXEN = VCC RXEN = TXEN = GND CC 0.09

23 A) MAX2411A-02 MAX2411A-03 MAX2411A-01 36 VCC = 5.5V µ 0.08 MAX2411A VCC = 5.5V 22 0.07 34 VCC = 4.0V 0.06 VCC = 4.0V 21 32 0.05 20 0.04 V = 5.5V 30 CC 19 0.03 VCC = 4.0V

VCC = 3.0V RECEIVE SUPPLY CURRENT (mA) VCC = 3.0V 0.02

28 18 SHUTDOWN SUPPLY CURRENT ( VCC = 3.0V TRANSMITTER SUPPLY CURRENT (mA) VCC = 2.7V VCC = 2.7V 0.01 VCC = 2.7V 26 17 0 -40 -15 10 35 60 85 -40 -15 10 35 60 85 -40 -15 10 35 60 85 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) STANDBY SUPPLY CURRENT LNA INPUT IMPEDANCE LNA OUTPUT IMPEDANCE vs. TEMPERATURE vs. FREQUENCY vs. FREQUENCY MAX2411A-05 MAX2411A-06 500 40 250 0 RXEN = TXEN = 2.0V 120 RXEN = VCC IMAGINARY A) MAX2411A-04 0 ) ) µ 400 100 200 -25 Ω Ω ) VCC = 5.5V ) RXEN = V Ω Ω CC IMAGINARY 80 -40 300 150 -50 VCC = 4.0V 60 -80 200 100 -75 40 -120 REAL IMPEDANCE ( REAL IMPEDANCE ( REAL IMAGINARY IMPEDANCE ( IMAGINARY IMPEDANCE ( REAL

STANDBY SUPPLY CURRENT ( 100 V = 3.0V 50 -100 CC 20 -160 VCC = 2.7V

0 0 -200 0 -125 -40 -15 10 35 60 85 0 0.5 1.0 1.5 2.0 2.5 3.0 0 0.5 1.0 1.5 2.0 2.5 3.0 TEMPERATURE (°C) FREQUENCY (GHz) FREQUENCY (GHz)

LNA GAIN vs. FREQUENCY LNA GAIN vs. TEMPERATURE LNA INPUT IP3 vs. TEMPERATURE 30 20 -5 1pF SHUNT CAPACITOR AT LNA INPUT RXEN = VCC RXEN = V USING EV KIT MATCHING CIRCUIT V = 5.5V -6 CC 19 CC MAX2411A-07 25 (OPTIMIZED FOR 1.9GHz) MAX2411A-08 MAX2411A-09 -7 V = 4.0V VCC = 3.0V 18 CC -8 20 RXEN = VCC VCC = 2.7V 17 -9 15 -10 16 VCC = 4.0V LNA GAIN (dB)

LNA GAIN (dB) -11 10 INPUT IP3 (dBm) -12 15 VCC = 2.7V VCC = 5.5V V = 3.0V -13 5 14 CC -14 0 13 -15 0 0.5 1.0 1.5 2.0 2.5 3.0 -40 -15 10 35 60 85 -40 -20 0 20 40 60 80 100 FREQUENCY (GHz) TEMPERATURE (°C) TEMPERATURE (°C)

4 ______Low-Cost RF Up/Downconverter with LNA and PA Driver

______Typical Operating Characteristics (continued) MAX2411A (MAX2411A EV kit, VCC = +3.0V, VGC = +2.15V, RXEN = TXEN = low, all measurements performed in 50Ω environment, fLO = 1.5GHz, PLO = -10dBm, fLNAIN = fPADRIN = fRXMXIN = 1.9GHz, PLNAIN = -32dBm, PPADRIN = PRXMXIN = -22dBm, fIF, IF = 400MHz, PIF = -32dBm (Note 1), all impedance measurements made directly to pin (no matching network), TA = +25°C, unless otherwise noted.)

LNA OUTPUT 1dB COMPRESSION POINT PA DRIVER INPUT IMPEDANCE LNA NOISE FIGURE vs. FREQUENCY vs. SUPPLY VOLTAGE vs. FREQUENCY MAX2411A-12 5.0 0 160 70 4.5 RXEN = V RXEN = V TXEN = VCC CC CC 140 30 MAX2411A-11 MAX2411A-10 -1 4.0 )

IMAGINARY Ω ) 120 -10

3.5 Ω -2 3.0 100 -50 2.5 -3 80 -90 2.0 60 -130 NOISE FIGURE (dB) -4

1.5 REAL IMPEDANCE (

40 -170 IMAGINARY IMPEDANCE ( 1.0 REAL -5 20 -210 0.5 OUTPUT 1dB COMPRESSION POINT (dBm) 0.0 -6 0 -250 100 480 860 1240 1620 2000 2.7 3.2 3.7 4.2 4.7 5.2 0 0.5 1.0 1.5 2.0 2.5 3.0 FREQUENCY (MHz) SUPPLY VOLTAGE (V) FREQUENCY (GHz)

PA DRIVER OUTPUT IMPEDANCE PA DRIVER GAIN AND OUTPUT IP3 vs. FREQUENCY PA DRIVER GAIN vs. FREQUENCY vs. GC VOLTAGE MAX2411A-13 200 50 30 20 TXEN = VCC USING EV KIT TXEN = VCC 175 0 MATCHING NETWORK 15 MAX2411A-15 25 MAX2411A-14 ) (OPTIMIZED FOR 1.9GHz) 10 IMAGINARY Ω ) 150 -50 IP3

Ω 5 20 TXEN = VCC 125 -100 0 GAIN 100 -150 15 -5 GAIN (dB) 75 -200 -10 10 REAL IMPEDANCE ( -15

50 -250 IMAGINARY IMPEDANCE (

GAIN (dB) OR OUTPUT IP3 (dBm) -20 REAL 5 25 -300 -25 0 -350 0 -30 0 0.5 1.0 1.5 2.0 2.5 3.0 0 0.5 1.0 1.5 2.0 2.5 3.0 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 FREQUENCY (GHz) FREQUENCY (GHz) GC VOLTAGE (V) PA DRIVER OUTPUT IP3 PA DRIVER OUTPUT 1dB COMPRESSION vs. TEMPERATURE PA DRIVER GAIN vs. TEMPERATURE vs. SUPPLY VOLTAGE 21 18 8 TXEN = VCC TXEN = VCC 20 MAX2411A-17 MAX2411A-16 17 6 MAX2411A-18 VGC = 2.15V VCC = 5.5V 19 16 VCC = 5.5V 4 18 VCC = 4.0V TXEN = VCC VCC = 4.0V 15 2 17 VCC = 3.0V

OUTPUT IP3 (dBm) 14 VCC = 2.7V PA DRIVER GAIN (dB) 0 16 VCC = 3.0V VCC = 2.7V

15 13 -2

OUTPUT 1dB COMPRESSION POINT (dBm) VGC = 1.0V 14 12 -4 -40 -20 0 20 40 60 80 100 -40 -15 10 35 60 85 2.7 3.2 3.7 4.2 4.7 5.2 5.7 TEMPERATURE (°C) TEMPERATURE (°C) SUPPLY VOLTAGE (V)

______5 Low-Cost RF Up/Downconverter with LNA and PA Driver

______Typical Operating Characteristics (continued) (MAX2411A EV kit, VCC = +3.0V, VGC = +2.15V, RXEN = TXEN = low, all measurements performed in 50Ω environment, fLO = 1.5GHz, PLO = -10dBm, fLNAIN = fPADRIN = fRXMXIN = 1.9GHz, PLNAIN = -32dBm, PPADRIN = PRXMXIN = -22dBm, fIF, IF = 400MHz, PIF = -32dBm (Note 1), all impedance measurements made directly to pin (no matching network), TA = +25°C, unless otherwise noted.)

PA DRIVER PA DRIVER NOISE FIGURE RECEIVE MIXER INPUT IMPEDANCE NOISE FIGURE vs. FREQUENCY vs. GAIN-CONTROL VOLTAGE vs. FREQUENCY MAX2410A-21 10 30 100 0 RXEN = VCC 9 90 -20 TXEN = VCC MAX2411A-20 MAX2411A-19 25 8 80 IMAGINARY -40 ) Ω

TXEN = VCC ) MAX2411A 7 Ω 70 -60 20 6 60 -80 5 15 50 -100 4 40 -120 NOISE FIGURE (dB) NOISE FIGURE (dB) 10 3 REAL IMPEDANCE ( 30 -140 IMAGINARY IMPEDANCE ( 2 20 REAL -160 5 1 10 -180 0 0 0 -200 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 FREQUENCY (GHz) GAIN-CONTROL VOLTAGE (V) FREQUENCY (GHz) RECEIVE MIXER CONVERSION RECEIVE MIXER INPUT IP3 RECEIVE MIXER CONVERSION GAIN GAIN vs. TEMPERATURE vs. TEMPERATURE vs. RF FREQUENCY 12 6 18 RXEN = VCC VCC = 5.5V IF = 400MHz 11 VCC = 4.0V 16 VCC = 5.5V 5 NARROW BAND MATCH MAX2411Atoc22

10 MAX2411Atoc23 14 MAX2411A toc24 AT RXMXIN, EV KIT 9 12 MATCH AT IF, IF 4 8 VCC = 2.7V 10 7 3 8 VCC = 3.0V 6 6 EV KIT

INPUT IP3 (dBm) V = 2.7V 2 CC MATCHING NETWORK

CONVERSION GAIN (dB) 5 CONVERSION GAIN (dB) 4 AT RXMXIN AND IFOUT 4 1 2 3 RXEN = VCC 0 RXEN = VCC 2 0 -2 -40 -20 0 20 40 60 80 -40 -20 0 20 40 60 80 0.5 1.0 1.5 2.0 2.5 3.0 TEMPERATURE (°C) TEMPERATURE (°C) RF FREQUENCY (GHz)

RECEIVE MIXER GAIN AND NOISE FIGURE IF OR IF OUTPUT IMPEDANCE TRANSMIT MIXER OUTPUT IMPEDANCE vs. LO POWER vs. FREQUENCY vs. FREQUENCY MAX2411Atoc26 MAX2411A-27 14 1000 0 300 0 TXEN = V 13 RXEN = V RXEN = V CC CC CC 250 -25 ) ) 12 MAX2411Atoc25 800 -300 Ω Ω

NOISE FIGURE ) ) 200 IMAGINARY -50

11 Ω IMAGINARY Ω 10 600 -600 150 -75 9 100 -100 GAIN 8 SINGLE-ENDED 400 -900 50 -125

7 REAL IMPEDANCE ( REAL IMPEDANCE ( REAL

IMAGINARY IMPEDANCE ( 0 -150 IMAGINARY IMPEDANCE ( GAIN AND NOISE FIGURE (dB) 6 200 -1200 5 REAL -50 -175 4 0 -1500 -100 -200 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 0 200 400 600 800 1000 0 0.5 1.0 1.5 2.0 2.5 3.0 LO POWER (dBm) FREQUENCY (MHz) FREQUENCY (GHz)

6 ______Low-Cost RF Up/Downconverter with LNA and PA Driver

TRANSMIT MIXER CONVERSION GAIN TRANSMIT MIXER CONVERSION GAIN TRANSMIT MIXER OUTPUT IP3 vs. TEMPERATURE vs. RF FREQUENCY vs. TEMPERATURE 12 10 3.5 TXEN = VCC NARROW BAND AT TXMXOUT, 9 TXEN = V VCC = 5.5V EV KIT MATCH AT IF, IF CC 10 MAX2411Atoc29 MAX2411Atoc28 8 2.5 VCC = 5.5V MAX2411A toc30 7 8 VCC = 2.7V 6 1.5 VCC = 4.0V VCC = 4.8V 6 5 EV KIT MATCH NETWORK 4 AT TXMXOUT AND IF, IF 0.5

4 OUTPUT IP3 (dBm) CONVERSION GAIN (dB)

CONVERSION GAIN (dB) 3 VCC = 3.0V 2 -0.5 2 1 TXEN = VCC VCC = 2.7V IF = 400MHz 0 0 -1.5 -40 -20 0 20 40 60 80 0.5 1.0 1.5 2.0 2.5 3.0 -40 -20 0 20 40 60 80 TEMPERATURE (°C) RF FREQUENCY (GHz) TEMPERATURE (°C)

TRANSMIT MIXER GAIN AND NOISE FIGURE IF OR IF OUTPUT IMPEDANCE vs. LO POWER vs. FREQUENCY LO PORT RETURN LOSS vs. FREQUENCY MAX2411Atoc32 10 1000 0 0 TXEN = VCC RXEN = V CC 5 RXEN = TXEN = VCC MAX2411A-33 MAX2411toc31 9 800 IMAGINARY -300 )

NF Ω

) 10 Ω 8 15 GAIN 600 -600 20 SINGLE-ENDED 7 400 -900 25 RETURN LOSS (dB) REAL IMPEDANCE ( 30 GAIN AND NOISE FIGURE (dB) 6 200 -1200 IMAGINARY IMPEDANCE ( REAL 35

5 0 -1500 40 -18 -15 -12 -9 -6 -3 0 0 200 400 600 800 1000 0 0.5 1.0 1.5 2.0 2.5 3.0 LO POWER (dBm) FREQUENCY (MHz) FREQUENCY (GHz)

______7 Low-Cost RF Up/Downconverter with LNA and PA Driver

______Pin Description

PIN NAME FUNCTION

1, 3, 4, 12, 14, GND Ground. Connect GND to the PC board ground plane with minimal inductance. 18, 20, 23, 28

RF Input to LNA. AC couple to this pin. At 1.9GHz, LNAIN can be easily matched to 50Ω with one 2 LNAIN external shunt 1pF capacitor.

Supply Voltage (2.7V to 5.5V). Bypass VCC to GND at each pin with a 47pF capacitor as close to 5, 10 VCC MAX2411A each pin as possible.

Logic-Level Enable for Receiver Circuitry. A logic high turns on the receiver. When TXEN and RXEN are both at a logic high, the part is placed in standby mode, with a 160µA (typical) supply 6 RXEN current. If TXEN and RXEN are both at a logic low, the part is set to shutdown mode, with a 0.1µA (typical) supply current. 7 LO 50Ω Local-Oscillator (LO) Input Port. AC couple to this pin.

50Ω Inverting Local-Oscillator Input Port. For single-ended operation, connect LO directly to 8 LO GND. If a differential LO signal is available, AC couple the inverted LO signal to this pin.

Logic-Level Enable for Transmitter Circuitry. A logic high turns on the transmitter. When TXEN and RXEN are both at a logic high, the part is placed in standby mode, with a 160µA (typical) 9 TXEN supply current. If TXEN and RXEN are both at a logic low, the part is set to shutdown mode, with a 0.1µA (typical) supply current.

Gain-Control Input for PA Driver. By applying an analog control voltage between 0V and 2.15V, the 11 GC gain of the PA driver can be adjusted over a 35dB range. Connect to VCC for maximum gain.

Power Amplifier Driver Output. AC couple to this pin. Use external shunt inductor to VCC to match 13 PADROUT PADROUT to 50Ω. This also provides DC bias. See the Typical Operating Characteristics for a plot of PADROUT Impedance vs. Frequency.

15, 17 GND PA Driver Input Grounds. Connect GND to the PC board ground plane with minimal inductance.

RF Input to Variable-Gain Power Amplifier Driver. Internally matched to 50Ω. AC couple to this 16 PADRIN pin. This input typically provides a 2:1 VSWR at 1.9GHz. AC couple to this pin. See the Typical Operating Characteristics for a plot of PADRIN Impedance vs. Frequency.

RF Output of Transmit Mixer (upconverter). Use an external shunt inductor to VCC as part of a 19 TXMXOUT matching network to 50Ω. This also provides DC bias. AC couple to this pin. See the Typical Operating Characteristics for a plot of TXMXOUT Impedance vs. Frequency.

Differential IF Port of Transmit (Tx) and Receive (Rx) Mixers, Inverting Side. In Rx mode, this output is an open collector and should be pulled up to VCC with an inductor. This inductor can be part of the matching network to the desired IF impedance in both Tx and Rx modes. Additionally, a resistor 21 IF may be placed across IF and IF to set a terminating impedance. In Tx mode, this input is internally AC-coupled; however, AC couple to this pin externally. For single-ended operation, connect this port to VCC and bypass with 1000pF capacitor to GND. Differential IF Port of Tx and Rx Mixers, Noninverting Side. In Rx mode, this output is an open collector and should be pulled up to VCC with an inductor. This inductor can be part of the matching net- 22 IF work to the desired IF impedance in both Tx and Rx modes. Additionally, a resistor may be placed across IF and IF to set a terminating impedance. In Tx mode, this input is internally AC coupled; however, AC couple to this pin externally.

8 ______Low-Cost RF Up/Downconverter with LNA and PA Driver

______Pin Description (continued) MAX2411A

PIN NAME FUNCTION

RF Input to Receive Mixer (downconverter). This input typically requires a matching network for 24 RXMXIN connecting to an external filter. AC couple to this pin. See the Typical Operating Characteristics for a plot of RXMXIN Impedance vs. Frequency.

25 GND Receive Mixer Input Ground. Connect GND to the PC board ground plane with minimal inductance. 26 GND LNA Output Ground. Connect GND to the PC board ground plane with minimal inductance. LNA Output. AC couple to this pin. This output typically provides a VSWR of better than 2:1 at frequencies from 1.7GHz to 3GHz with no external matching components. At other frequencies, a 27 LNAOUT matching network may be required to match LNAOUT to an external filter. Consult the Typical Operating Characteristics for a plot of LNA Output Impedance vs. Frequency.

______Detailed Description proper operation. These inductors are typically used as part of an IF matching network. The MAX2411A consists of five major components: a transmit mixer followed by a variable-gain power- In transmit mode, IF and IF are high-impedance inputs amplifier (PA) driver as well as a low-noise amplifier that are internally AC coupled to the transmit mixer. (LNA), receive mixer, and power-management section. This internal AC coupling prevents the DC bias voltage required for the receive mixer outputs from reaching The following sections describe each of the blocks in the transmit mixer inputs. the MAX2411A Functional Diagram. Receive Mixer Low-Noise Amplifier (LNA) The receive mixer is a wideband, double-balanced The LNA is a wideband, single-ended cascode amplifi- design with excellent noise figure and linearity. Inputs to er that can be used over a wide range of frequencies. the mixer are the RF signal at the RXMXIN pin and the Refer to the LNA Gain vs. Frequency graph in the LO inputs at LO and LO. The downconverted output sig- Typical Operating Characteristics. Its port impedances nal appears at the IF port. For more information, see the are optimized for operation around 1.9GHz, requiring Bidirectional IF Port section. The conversion gain of the only a 1pF shunt capacitor at the LNA input for a VSWR receive mixer is typically 9.4dB with a 9.2dB noise figure. of better than 2:1 and a noise figure of 2.4dB. As with every LNA, the input match can be traded off for better RF Input noise figure. The RXMXIN input is typically connected to the LNA output through an off-chip filter. This input is externally PA Driver matched to 50Ω. See the Typical Operating Circuit for an The PA driver has typically 15dB of gain, which is example matching network and the Receive Mixer Input adjustable over a 35dB range via the GC pin. At full gain, Impedance vs. Frequency graph in the Typical Operating the PA driver has a noise figure of 3.5dB at 1.9GHz. Characteristics. For input and output matching information, refer to the Typical Operating Characteristics for plots of PA Driver Local-Oscillator Inputs Input and Output Impedance vs. Frequency. The LO and LO pins are internally terminated with 50Ω on-chip resistors. AC couple the local-oscillator signal Bidirectional IF Port to these pins. If a single-ended LO source is used, con- The MAX2411A has a unique bidirectional differential IF nect LO directly to ground. port, which can eliminate the need for separate transmit and receive IF filters, reducing cost and component count. Transmit Mixer Consult the Typical Operating Circuit for more information. The transmit mixer takes an IF signal at the IF port and For single-ended operation, connect the unused IF port to upconverts it to an RF frequency at the TXMXOUT pin. VCC and bypass with a 1000pF capacitor to GND. For more information on the IF port, see the Bidirectional IF Port section. The conversion gain is typically 8.5dB, In receive mode, the IF and IF pins are open-collector and the output 1dB compression point is typically outputs that need external inductive pull-ups to V for CC 11.1dBm at 1.9GHz.

______9 Low-Cost RF Up/Downconverter with LNA and PA Driver

RF Output Table 1. Advanced System Power- The transmit mixer output appears on the TXMXOUT pin, an open-collector output that requires an external Management Function pull-up inductor for DC biasing, which can be part of an impedance matching network. Consult the Typical RXEN TXEN FUNCTION Operating Characteristics for a plot of TXMXOUT 0 0 Shutdown Impedance vs. Frequency. 0 1 Transmit Advanced System Power Management 1 0 Receive RXEN and TXEN are the two separate power-control 1 1 Standby mode inputs for the receiver and transmitter. If both inputs MAX2411A are at logic 0, the part enters shutdown mode, and at RF frequencies other than those specified in the AC the supply current drops below 1µA. When one input Electrical Characteristics table, it may be necessary to is brought to logic 1, the corresponding function is design or alter the matching networks on the RF ports. If enabled. If RXEN and TXEN are both set to logic 1, the the IF frequency is different from that specified in the AC part enters standby mode, as described in the Standby Electrical Characteristics table, the IF, IF matching net- Mode section. Table 1 summarizes these operating work must also be altered. The Typical Operating modes. Characteristics provide port impedance data versus fre- Power-down is guaranteed with a control voltage at or quency on all RF and IF ports for use in designing below 0.6V. The power-down function is designed to matching networks. The LO port (LO and LO) is internal- reduce the total power consumption to less than 1µA in ly terminated with 50Ω resistors and provides a VSWR of less than 2.5µs. Complete power-up happens in the approximately 1.2:1 to 2GHz and 2:1 up to 3GHz. same amount of time. Layout Issues Standby Mode A properly designed PC board is essential to any When the TXEN and RXEN pins are both set to logic 1, RF/microwave circuit. Be sure to use controlled imped- all functions are disabled, and the supply current drops ance lines on all high-frequency inputs and outputs. to 160µA (typ); this mode is called Standby. This mode Use low-inductance connections to ground on all GND corresponds to a standby mode on the compatible IF pins, and place decoupling capacitors close to all VCC transceiver chips MAX2510 and MAX2511. connections. ______Applications Information For the power supplies, a star topology works well. Each VCC node in the circuit has its own path to the Extended Frequency Range central VCC and a decoupling capacitor that provides a The MAX2411A has been characterized at 1.9GHz for low impedance at the RF frequency of interest. The use in PCS-band applications. However, it operates central VCC node has a large decoupling capacitor over a much wider frequency range. The LNA gain and as well. This provides good isolation between the noise figure, PA driver gain, and mixer conversion gain different sections of the MAX2411A. The MAX2411A are plotted over a wide frequency range in the Typical EV kit layout can be used as a guide to integrating the Operating Characteristics. When operating the device MAX2411A into your design.

10 ______Low-Cost RF Up/Downconverter with LNA and PA Driver

______Typical Application Block Diagram MAX2411A

RF BPF

MATCH

IF LNAIN IF MATCH ANTENNA IF IF BPF T/R RF BPF TXEN POWER RXEN MANAGEMENT LO LOCAL OSCILLATOR MAX2411 LO

PA DRIVER

PA MATCH PADROUT

RF BPF GC

RF BPF MATCH

______11 Low-Cost RF Up/Downconverter with LNA and PA Driver

______Typical Operating Circuit

1 28 GND GND 220pF 220pF LNA INPUT 2 27 LNA (1.9GHz) LNAIN LNAOUT OUTPUT 1pF 3 26 GND GND 4 25 GND GND MAX2411A VCC 3.9nH 220pF 5 24 Rx MIXER V RXMXIN CC MAX2411A INPUT (1.9GHz) 47pF 23 VCC GND 27nH

7 27nH 1000pF LO INPUT LO 22 IF 220pF 1000pF 8 400MHz LO 21 27nH IF V VCC CC 1000pF IF SAW 10 FILTER VCC 27nH (200Ω) 47pF 20 1000pF GND VCC 17 GND 18 1000pF GND

18nH VCC 220pF PA OUTPUT 13 (1.9GHz) PADROUT 1000pF 12 GND 5.6nH 14 GND 3.9nH 220pF 19 Tx MIXER TXMXOUT OUTPUT 9 TXEN TXEN (1.9GHz) 6 RXEN RXEN 220pF 16 PA DRIVER 11 GC GC PADRIN INPUT

15 GND

12 ______Low-Cost RF Up/Downconverter with LNA and PA Driver

Package Information MAX2411A QSOP.EPS

______13 Low-Cost RF Up/Downconverter with LNA and PA Driver

NOTES

MAX2411A

14 ______Mouser Electronics

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