0.1µF ±5% ceramic capacitors (0603) Murata GRM188R71C104KA01 C13, C16, C18, C19 JU1, JU2, JU5, JU6. Maxim Integrated Products 1

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1 9-97; Rev 0; /05 MAX70 Evaluation Kit General Description The MAX70 evaluation kit (EV kit) allows for a detailed evaluation of the MAX70 superheterodyne receiver. It enables testing of the device s RF performance and requires no additional support circuitry. The RF input uses a 50Ω matching network and an SMA connector for convenient connection to test equipment. The EV kit can also directly interface to the user s embedded design for easy data decoding. The MAX70 EV kit comes in two versions: 5MHz and 4.9MHz. The passive components are optimized for these frequencies. These components can easily be changed to work at RF frequencies from 00MHz to 450MHz. In addition, the received data rate can be adjusted from 0 to 66kbps by changing three more components. For easy implementation into the customer s design, the MAX70 EV kit also features a proven PC board layout, which can be easily duplicated for quicker time to market. The EV kit Gerber files are available for download at Features Proven PC Board Layout Proven Components Parts List Multiple Test Points Provided On Board Available in 5MHz or 4.9MHz Optimized Versions Adjustable Frequency Range from 00MHz to 450MHz Fully Assembled and Tested Can Operate as a Stand-Alone Receiver with the Addition of an Antenna Requires component changes. Ordering Information PART TEMP RANGE IC PACKAGE MAX70EVKIT-5-40 C to +85 C 8 TSSOP MAX70EVKIT-4-40 C to +85 C 8 TSSOP Evaluates: MAX70 C, C, C C C4 C5 C6, C0 C7, C8, C (5MHz) (4MHz) 0.0µF ±0% ceramic capacitors Murata GRM88R7H0KA0 500pF ±0%, 50V X7R ceramic capacitor Murata GRM88R7H5KA0 0.47µF 80% to 0% ceramic capacitor Murata GRM88F5C474ZA0 470pF ±5% ceramic capacitor Murata GRM885CH47JA0 0pF ±5% ceramic capacitors Murata GRM885CHJA0 00pF ±5% ceramic capacitors Murata GRM885CH0JA0 4.0pF ±0.pF ceramic capacitor Murata GRM885CH4R0BZ0.pF ±0.pF ceramic capacitor Murata GRM885CHRBD0 Component List C, C0, C4 0.µF ±5% ceramic capacitors Murata GRM88R7C04KA0 C, C6, C8, 0 Not installed C4, C5 5pF ±5%, 50V ceramic capacitors Murata GRM885CH50JZ0 C7 0 Not installed, 0.0µF 80% to 0% ceramic capacitor Murata GRM88R7H0KA0 C 0pF ±5%, 50V ceramic capacitor Murata GRM885CH00JZ0 C F_IN 0 JU, JU, JU5, JU pF ±0%, 50V X7R ceramic capacitor Murata GRM88R7H0KA0 Not installed, SMA connector, edge mount Johnson pin headers Digi-Key S0-6-ND or equivalent Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 MAX70 Evaluation Kit Evaluates: MAX70 JU, JU4 0 Not installed JU7 -pin header JU8 Shorted L (5MHz) L (4MHz) L (5MHz) L (4MHz) L 7nH ±5% inductor Coilcraft 060CS-7NXJB 5nH ±5% inductor Coilcraft 060CS-5NXJB 0nH ±5% inductor Coilcraft 060CS-RXJB 56nH ±5% inductor Coilcraft 060CS-56NXJB 5nH ±5% inductor Murata LQG8HN5NJ00 MIX_OUT 0 Not installed, SMA connector, top mount Digi-Key J500-ND Johnson R 5.kΩ resistor, any R, R4, R6 0 Not installed, resistors R 0 Not installed, 70Ω resistor any R5 0kΩ resistor, any R7 0Ω resistor R8 0kΩ resistor, any RF_IN SMA connector, top mount Digi-Key J500-ND Johnson TP, TP4 TP 0 Not installed, GND, SHDN, AGC_C, DATA_OUT, TP Y (5MHz) Y (4MHz) Component List (continued) 6 Test points Mouser 5-0 or equivalent MHz crystal Hong Kong Crystals SSL E0FAFZ8A0 or Crystek MHz crystal Hong Kong Crystals SSL668E0FAFZ8A0 or Crystek Y 0.7MHz ceramic filter Murata SFTLA0M7FA00-B0 U MAX70EUI MAX70 EV kit PC board 5 Shunts (JU) Digi-Key S9000-ND or equivalent Quick Start The following procedures allow for proper device evaluation. Required Test Equipment Regulated power supply capable of providing RF signal generator capable of delivering from -0dBm to 0dBm of output power at the operating frequency, in addition to AM or pulse-modulation capabilities (Agilent E440B or equivalent) Optional ammeter for measuring supply current Oscilloscope Connections and Setup This section provides a step-by-step guide to operating the EV kit and testing the device s functionality. Do not turn on the DC power or RF signal generator until all connections are made: ) Connect a DC supply set to (through an ammeter if desired) to the and GND terminals on the EV kit. Do not turn on the supply. ) Connect the RF signal generator to the RF_IN SMA connector. Do not turn on the generator output. Set the generator for an output frequency of 5MHz (or 4.9MHz) at a power level of -00dBm. Set the modulation of the generator to provide a khz, 00%, AM-modulated square wave (or a khz pulse-modulated signal). ) Connect the oscilloscope to test point TP. 4) Turn on the DC supply. The supply current should read approximately 5mA. 5) Activate the RF generator s output without modulation. The scope should display a DC voltage that varies from approximately.v to.0v as the RF generator amplitude is changed from -5dBm to 0dBm. (Note: At an amplitude of around -60dBm, this DC voltage drops suddenly to approximately.5v and then starts rising again with increasing input amplitude. This is normal; the AGC is turning on the LNA gain-reduction resistor.) 6) Set the RF generator to -00dBm. Activate the RF generator s modulation and set the scope s cou-

3 MAX70 Evaluation Kit Component Suppliers SUPPLIER PHONE FAX Coilcraft Crystek Hong Kong Crystal Murata Note: Indicate that you are using the MAX70 when contacting these component suppliers. pling to AC. The scope now displays a lowpass-filtered square wave at TP (filtered analog baseband data). Use the RF generator s LF OUTPUT (modulation output) to trigger the oscilloscope. 7) Monitor the DATA_OUT terminal and verify the presence of a khz square wave. Additional Evaluation ) With the modulation still set to AM, observe the effect of reducing the RF generator s amplitude on the DATA_OUT terminal output. The error in this sliced digital signal increases with reduced RF signal level. The sensitivity is usually defined as the point at which the error in interpreting the data (by the following embedded circuitry) increases beyond a set limit (BER test). ) With the above settings, a 5MHz-tuned EV kit should display a sensitivity of about -4dBm (0.% BER) while a 4.9MHz kit displays a sensitivity of about -dbm (0.% BER). Note: The above sensitivity values are given in terms of average. ) Capacitors C5 and C6 are used to set the corner frequency of the nd-order lowpass Sallen-Key data filter. The current values were selected for bit rates up to kbps. Adjusting these values accommodates higher data rates (refer to the MAX70 data sheet for more details). Layout Issues A properly designed PC board is an essential part of any RF/microwave circuit. On high-frequency inputs and outputs, use controlled-impedance lines and keep them as short as possible to minimize losses and radiation. At high frequencies, trace lengths that are on the order of λ/0 or longer can act as antennas. Keeping the traces short also reduces parasitic inductance. Generally, in of a PC board trace adds about 0nH of parasitic inductance. The parasitic inductance can have a dramatic effect on the effective inductance. For example, a 0.5in trace connecting a 00nH inductor adds an extra 0nH of inductance or 0%. To reduce the parasitic inductance, use wider traces and a solid ground or power plane below the signal traces. Also, use low-inductance connections to ground on all GND pins, and place decoupling capacitors close to all connections. The EV kit PC board can serve as a reference design for laying out a board using the MAX70. All required components have been enclosed in.5in x.5in, which can be directly inserted in the application circuit. Detailed Description Power-Down Control The MAX70 can be controlled externally using the SHDN connector. The IC draws approximately.5µa in shutdown mode. Jumper JU is used to control this mode. The shunt can be placed between pins and for continuous shutdown, or pins and for continuous operation. Remove JU shunt for external control. See Table for the jumper function descriptions. Table. Jumper Function JUMPER STATE FUNCTION JU JU JU JU4 JU5 JU6 JU7 - Normal operation - Power-down mode N.C. External power-down control - Crystal divide ratio = - Crystal divide ratio = 64 - Mixer output to MIX_OUT - External IF input N.C. Normal operation - Uses PDOUT for faster receiver startup - GND connection for peak detector filter - Disable AGC - Enable AGC N.C. External control of AGC lock function - IR centered at 4MHz - IR centered at 5MHz N.C. IR centered at 75MHz - Connect to supply N.C. Connect to +5.0V supply Evaluates: MAX70

4 MAX70 Evaluation Kit Evaluates: MAX70 Power Supply The MAX70 can operate from.v or 5V supplies. For 5V operation, remove JU7 before connecting the supply to. For.V operation, connect JU7. IF Input/Output The 0.7MHz IF can be monitored with the help of a spectrum analyzer using the MIX_OUT SMA (not provided). Remove the ceramic filter for such a measurement and include R (70Ω) and C7 (0.0µF) to match the 0Ω mixer output with the 50Ω spectrum analyzer. Jumper JU needs to connect pins and. It is also possible to use the MIX_OUT SMA to inject an external IF as a means of evaluating the baseband data slicing section. Jumper JU needs to connect pins and. F_IN External Frequency Input For applications where the correct frequency crystal is not available, it is possible to directly inject an external frequency through the F_IN SMA (not provided). Connect the SMA to a function generator. The addition of C8 and is necessary (use 0.0µF capacitors). AGC Control Jumper JU5 controls whether the AGC is enabled. Connect pins and to enable the AGC. In addition, by removing the jumper, the AGC setting can be locked or unlocked by transitioning the AC pin while the SHDN pin is high. Crystal Select Jumper JU controls the crystal-divide ratio. Connecting pins and sets the divide ratio to, while connecting pins and sets the ratio to 64. This determines the frequency of the crystal to be used. Image-Rejection Frequency Select A unique feature of the MAX70 is its ability to vary at which frequency the image rejection is optimized. JU6 allows the selection of three possible frequencies: 5MHz, 75MHz, and 4.9MHz. See Table for settings. Test Points and I/O Connections Additional test points and I/O connectors are provided to monitor the various baseband signals and for external connections. See Tables and for a description. For additional information and a list of application notes, visit Table. Test Points TP Table. I/O Connectors SIGNAL RF_IN F_IN MIX_OUT GND DATA_OUT SHDN AGC_C RF input DESCRIPTION External reference frequency input IF input/output Ground Supply input Sliced data output External power-down control AGC control DESCRIPTION Data slicer negative input Data filter output 4 Peak detector out 5 6 GND 7 Data filter feedback node 8 Data out 9 Power-down select input 0 AGC control Crystal select 4

5 MAX70 Evaluation Kit Evaluates: MAX70 L L Y AT 5MHz 4pF 7nH 0nH MHz C8 RF_IN L GND TP6 JU7 C0 TP5 0.µF TP0 AT 4.9MHz.pF 5nH 56nH 6.68MHz C7 00pF L C 0.µF L 5nH C 0.0µF C0 0pF JU6 C 0.0µF C 00pF C8 00pF C4 5pF Y C5 5pF C6 8 XTAL XTAL SHDN 7 A 6 U PDOUT LNAIN MAX LNASRC AGND 6 5 LNAOUT DATAOUT 7 A MIXIN 9 MIXIN DSP 0 AGND IRSEL DFFB OPP DSN 0 MIXOUT DFO 9 DGND 4 8 D IFIN IFIN XTALSEL 7 6 AC 5 Y 0.7MHz IN GND OUT R C 0.0µF JU8 C 000pF C6 0pF R 5.kΩ C 500pF TP F_IN JU TP9 SHDN TP4 C JU4 DSN R5 TP8 0kΩ DATA_OUT C4 0.µF C 0pF R7 0Ω R6 TP7 C5 470pF C4 0.47µF DSN TP TP R8 0kΩ TP JU JU R C7 R4 MIX_OUT AGC_C JU5 Figure. MAX70 EV Kit Schematic 5

6 MAX70 Evaluation Kit Evaluates: MAX70 Figure. MAX70 EV Kit Component Placement Guide Component Side Figure. MAX70 EV Kit PC Board Layout Component Side 6

7 MAX70 Evaluation Kit Evaluates: MAX70 Figure 4. MAX70 EV Kit PC Board Layout Solder Side 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, 0 San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.