MAX2683/MAX2684 Evaluation Kits

Transcription

1 9-6; Rev ; / MAX68/MAX684 Evaluation Kits General Description The MAX68/MAX684 evaluation kits (EV kits) simplify evaluation of the MAX68/MAX684.4GHz to.8ghz downconverter mixers. The EV kits are fully assembled and tested, allowing simple evaluation of all device functions. All signal ports utilize SMA connectors, providing a convenient interface to RF test equipment. The MAX68/MAX684 are downconversion mixers intended for operation in the.4ghz to.8ghz frequency range. The MAX68 is optimized for downconversion to IF frequencies between MHz and 4MHz, and allows high-side or low-side LO injection. The MAX684 is optimized for IF frequencies between 8MHz to MHz and only allows low-side LO injection. A logiclevel enabled LO frequency doubler allows the external LO source to run at half frequency, or at full frequency if disabled. As assembled, the MAX68/MAX684 EV kits are configured for operation of the LO at half frequency. A few simple component changes configure the EV kit for operation of the LO at full frequency. In addition, an external resistor allows adjustment of device linearity and supply current. C C C, C6, C C4 C5 C7 C8, C9 C JU L pf ±% ceramic capacitor (4) Murata GRM6X7RK5 or Taiyo Yuden UMK5BKW pf ±.pf ceramic capacitor (6) Murata GRM9COGB5 pf ±5% ceramic capacitors (6) Murata GRM9COGJ5 or Taiyo Yuden UMK7CHJZ µf, V tantalum capacitor AVX TAJB6M pf ±% ceramic capacitor (6) Murata GRM9X7RK5 8.pF ±.5pF ceramic caps (6) Murata GRM9COG8RC5 or Taiyo Yuden UMK7CH8RCZ.pF ±.pf ceramic cap (6) Murata GRM9COGRB5 -pin header.nh ±.nh inductor (4) Murata LQPANC Features Easy Evaluation of MAX68/MAX684 All Critical Peripheral Components Included SMA Input and Output Signal Connectors RF Input Matched to 5Ω at 6MHz IF Output Matched to 5Ω at MHz (MAX68) IF Output Matched to 5Ω at 9MHz (MAX684) Fully Assembled and Tested PART MAX68EVKIT MAX684EVKIT *Exposed paddle L, L4 R, R R RFIN, LOX, IF T U VCC, Ordering Information TEMP. RANGE -4 C to +85 C -4 C to +85 C IC PACKAGE 6 TSSOP-EP* 6 TSSOP-EP* MAX68 Component List 9nH ±5% inductors (6) Murata LQGA9NJ.9nH ±nh inductor (6) Murata LQGAN9S.kΩ ±% resistors (6).5kΩ ±% resistor (6) SMA connectors (PC edge mount) EFJohnson Balun transformer, B4F type Toko 67DB-8 MAX68EUE (6-pin TSSOP) Test points Shunt (JU) MAX68/MAX684 PC board MAX68/MAX684 data sheet MAX68/MAX684 EV kit data sheet Evaluate: MAX68/MAX684 Maxim Integrated Products For free samples and the latest literature, visit maxim-ic.com or phone For small orders, phone

2 MAX68/MAX684 Evaluation Kits Evaluate: MAX68/MAX684 C C C, C6, C C4 C5 C7 C8, C9 C JU L µf, V tantalum capacitor AVX TAJB6M pf ±% ceramic cap (6) Murata GRM9X7RK5 8.pF ±.5pF ceramic caps (6) Murata GRM9COG8RC5 or Taiyo Yuden UMK7CH8RCZ -pin header.nh ±.nh inductor (4) Murata LQPANC SUPPLIER PHONE FAX pf ±% ceramic cap (4) Murata GRM6X7RK5 or Taiyo Yuden UMK5BKW pf ±.pf ceramic capacitor (6) Murata GRM9COGB5 pf ±5% ceramic capacitors (6) Murata GRM9COGJ5 or Taiyo Yuden UMK7CHJZ AVX EFJohnson Murata Taiyo Yuden Component Suppliers Toko 8-PIK-TOKO WEB avxcorp.com efjohnson.com murata.com T-Yuden.com tokoam.com Test Equipment Required This section lists the test equipment required for evaluating the MAX68/MAX684: One power supply capable of providing ma of supply current over the supply voltage range of +.7V to +5.5V. L, L4 R, R R RFIN, LOX, IF T U VCC, MAX684 Component List 6.8nH ±5% inductors (6) Murata LQGA6N8J.9nH ±.nh inductor (6) Murata LQGAN9S.kΩ ±% resistors (6) Ω ±% resistor (6) SMA connectors (PC edge mount) EFJohnson Balun transformer, B4F type Toko 67DB-8 MAX684EUE (6-pin TSSOP) Test points Shunt (JU) MAX68/MAX684 PC board MAX68/MAX684 data sheet MAX68/MAX684 EV kit data sheet Two low-noise RF-signal generators or equivalent (5Ω) sine-wave sources capable of delivering at least dbm of output power up to 4GHz. One generator is required for the RF signal source, while the second generator is required for the LO signal source. One HP 856E RF-spectrum analyzer or equivalent that covers the downconverter mixer s output frequency range, as well as a few harmonics (6GHz). Three 5Ω SMA cables (RG-58A/U or equivalent). Optional: digital multimeters (DMMs) to monitor DC supply voltage and supply current. Connections and Setup This section provides step-by-step instructions for getting the EV kit up and running: ) DC Power Supply: Set the power-supply voltage to +5V. Turn the power supply off and connect it to the VCC and connections on the EV kit. If desired, place an ammeter in series with the power supply to measure supply current and a voltmeter in parallel with the VCC and connections to measure the supply voltage delivered to the device.

3 MAX68/MAX684 Evaluation Kits ) RF Signal Source: Set one signal generator to an RF frequency of.6ghz at an output power level of -dbm. Turn the output of the signal generator off. Connect the signal generator to the RF port SMA connector using a 5Ω SMA cable. ) LO Signal Source: The MAX68/MAX684 can be configured for full- or half-frequency operation of the external LO signal source. As assembled, the MAX68/MAX684 EV kits are configured for halffrequency operation of the LO signal source. The half-frequency LO port, LOX, is coupled to the MAX68/MAX684 EV kit LO port SMA connector, while the LOX port is left unconnected. To evaluate the devices with the LO doubler enabled, be sure jumper JU is shorted to (ENX = ). Set the LO signal generator output power to -5dBm at a frequency of 65MHz (MAX68) or 5MHz (MAX684). Turn the output of the signal generator off. Connect the signal generator to the LO port SMA connector using a 5Ω SMA cable. Evaluation of the devices with full-frequency operation of the LO signal source requires two component changes. Remove inductor and leave the LOX port unconnected. Short the unpopulated pads of resistor with a Ω resistor. Disable the LO frequency doubler by shunting jumper JU to VCC (ENX = VCC). Set the LO signal generator output power to -5dBm, at a frequency of MHz (MAX68) or 7MHz (MAX684). Turn the output of the signal generator off. Connect the signal generator to the LO port SMA connector using a 5Ω SMA cable. 4) Spectrum Analyzer: Connect the spectrum analyzer to the IF port SMA connector using a 5Ω SMA cable. Set the center frequency of the spectrum analyzer to MHz (MAX68) or 9MHz (MAX684). Set the reference level of the spectrum analyzer to -dbm and the span to MHz. Analysis Turn on the power supply and RF and LO signal generators. The ammeter should read approximately 55mA with the LO doubler enabled (ENX = ) or 4mA with the LO doubler disabled (ENX = V CC ). If evaluating the MAX68, the spectrum analyzer should show an output power of approximately -4dBm at a center frequency of MHz. If evaluating the MAX684, the output power should read approximately -dbm at a center frequency of 9MHz. Be sure to take into account cable, board, and balun losses when calculating power gain. Typical balun losses are.db at MHz for the MAX68 EV kit and.8db at 9MHz for the MAX684 EV kit. Detailed Description This section describes the circuitry surrounding the MAX68/MAX684 EV kits. Figure is the schematic for the MAX68/MAX684 EV kits as assembled. For more detailed information covering device operation, refer to the MAX68/MAX684 data sheet. RF Input The RFIN port of the MAX68/MAX684 is internally biased and requires a DC-blocking capacitor, as well as a matching network for optimum power transfer. Capacitor C functions as a DC block, while inductor L and capacitor C function as a matching network, tuning the RF input of the device for maximum gain at.6ghz. LO Input and LO Frequency Doubler Control The MAX68/MAX684 include a logic-level-enabled LO frequency doubler. Jumper JU controls the LO doubler. A logic-level low on the ENX pin enables the frequency doubler, and the external LO signal source operates at half frequency. A logic-level high on the ENX pin disables the frequency doubler, and the external LO signal source operates at full frequency. Half-frequency LO signals are applied to the LOX port, while full-frequency LO signals are applied to the LOX port. Both ports are internally biased and require a DC-blocking capacitor. The unused LO port should be left unconnected. The MAX68/MAX684 EV kits, as assembled, are configured for operation of the LO signal source at half frequency. Capacitor C6 functions as a DC block, while inductor improves the return loss of the port. The LOX port is left unconnected for half-frequency operation. To evaluate the device with full-frequency operation of the LO source, remove inductor and leave the LOX port unconnected (Figure ). Short resistor with a Ω resistor. Capacitor C6 now functions as the DC block for the LOX port. IF Output The MAX68/MAX684 incorporate differential, opencollector IF output ports for use in either differential or single-ended applications. To ease evaluation of the devices, the MAX68/MAX684 EV kits utilize a balun to convert the differential signal to a single-ended signal compatible with 5Ω test equipment. The IF output of the MAX68 is tuned for an IF frequency of MHz, while the IF output of the MAX684 is tuned for an IF frequency of 9MHz. Inductors L and L4 provide DC biasing and impedance matching of the Evaluate: MAX68/MAX684

4 MAX68/MAX684 Evaluation Kits Evaluate: MAX68/MAX684 VCC SMA RFIN LOX LO MODE LOX VCC SMA LOX C4 µf V C pf JU C6 pf C pf C pf R.k C pf L.nH.9nH OPEN C5 OPEN IFOUT+, and IFOUT- ports. Resistor R resistively terminates the IF output. Capacitors C8 and C9 provide impedance matching in addition to DC blocking. In the MAX68, C is also part of an impedance-matching network. The balun provides differential to single-ended conversion as well as 4: impedance transformation. The IF output is then connected to the IF port SMA connector V CC RFIN ENX LOX LOX Figure. MAX68/MAX684 EV Kits Schematic LO INPUT C6 pf OPEN SHORT Figure. MAX68/MAX684 Full-Frequency LO Port Configuration 7 8 LOX LOX MAX68 MAX684 U MAX68 MAX684 BIAS 6 5 IFOUT+ 4 IFOUT- 9 R.k L* 9nH R*.5k L4* 9nH VCC C8 8.pF C*.pF C7 pf C9 8.pF T BALUN TOKOB4F Linearity and Supply Current Adjustment The MAX68/MAX684 allow the linearity and supply current of the device to be adjusted via an external resistor, R, to ground. Increased linearity also results in increased supply current. The MAX68/MAX684 EV kits are assembled with a nominal R value of.kω. Replace R with a resistor value in the range of 8Ω to kω to experiment with the linearity of the device. Layout and Bypassing Good PC board layout is an essential aspect of RF circuit design. The EV kits PC board can serve as a guide for laying out a board using the MAX68/MAX684. Keep PC board trace lengths as short as possible to minimize parasitics and losses. Keep bypass capacitors as close to the device as possible with low-inductance connections to the ground plane. Capacitor C4, placed near the VCC connection, and capacitors C and C7, placed near the device, help to reduce any high-frequency crosstalk. Capacitor C and resistor R, placed near the ENX pin on the device, help to filter out any noise that may be coupled into the ENX pin. 4 6 SMA IF * VALUES ARE FOR MAX68 EV KIT ONLY. REFER TO COMPONENT LIST FOR MAX684 VALUES. 4

5 MAX68/MAX684 Evaluation Kits." Figure. MAX68/MAX684 EV Kits PC Board Layout Component Placement Guide." Figure 4. MAX68/MAX684 EV Kits PC Board Layout Component Side Evaluate: MAX68/MAX684." Figure 5. MAX68/MAX684 EV Kits PC Board Layout Ground Planes and." Figure 6. MAX68/MAX684 EV Kits PC Board Layout Solder Side 5

6 MAX68/MAX684 Evaluation Kits Evaluate: MAX68/MAX684 NOTES 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. 6 Maxim Integrated Products, San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.