19-2978; Rev 0; 9/03 MAX5885 Evaluation Kit Ordering Information PART TEMP RANGE MAX5885EVKIT 0°C to +70°C Features ♦ Fast Evaluation and Performance Testing ♦ CMOS Compatible ♦ SMA Coaxial Connectors for Clock Input and Analog Output ♦ 50Ω Matched Clock Input and Analog Output Signal Lines ♦ Single-Ended to Differential Clock Signal Conversion Circuitry ♦ Differential Current Output to Single-Ended Voltage Signal Output Conversion Circuitry ♦ Full-Scale Current Output Configured for 20mA ♦ External 1.25V Reference Source Available IC PACKAGE ♦ Fully Assembled and Tested 48 QFN-EP* ♦ Also Evaluates the 14-Bit MAX5884 and 12-Bit MAX5883 *EP = Exposed pad. Component List DESIGNATION C1 C2–C13 C14, C17, C20, C25 C15, C18, C21, C26 QTY DESCRIPTION 0 Not installed, ceramic capacitor (0603) 12 0.1µF ±10%, 10V X5R ceramic capacitors (0402) TDK C1005X5R1A104K or Taiyo Yuden LMK105BJ104KV 4 4 47µF ±10%, 6.3V tantalum capacitors (B) AVX TAJB476K006R or Kemet T494B476K006AS 10µF ±10%, 10V tantalum capacitors (A) AVX TAJA106K010R or Kemet T494A106K010AS 4 1µF ±10%, 10V X5R ceramic capacitors (0603) TDK C1608X5R1A105K C23, C24 0 Not installed, ceramic capacitor (0805) CLK, OUT 2 SMA PC-mount vertical connectors IOUTP, IOUTN 2 Scope probe jacks J1 1 2 x 20 pin surface-mount header Samtec TSM-120-02-S-MT C16, C19, C22, C27 DESIGNATION QTY JU1 1 3-pin header DESCRIPTION JU2–JU5 4 2-pin headers L1–L4 4 Chip bead core inductors Panasonic EXC-CL-4532U1 R1, R2 2 49.9Ω ±0.1% resistors (0603) IRC PFC-W0603R-03-49R9-B R3 1 100Ω ±1% resistor (0603) R4, R5, R6 0 Not installed, resistors (0603) R7 1 2kΩ ±1% resistor (0603) R8–R26 19 0Ω ±5% resistors (0402) R27, R28 2 24.9Ω ±1% resistors (0402) R29–R45 0 Not installed, resistors (0402) T1, T3 2 Transformers Mini-Circuits ADTL1-12 T2 1 Transformer Coilcraft TTWB3010-1 TP1–TP4 4 PC test points, black TP5 1 PC test point, red U1 1 MAX5885EGM (48-pin QFN-EP) U2 1 1.25V voltage reference (8-pin SO) Maxim MAX6161AESA None 5 Shunts (JU1–JU5) None 1 MAX5885 PC board ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 Evaluates: MAX5883/MAX5884/MAX5885 General Description The MAX5885 evaluation kit (EV kit) is a fully assembled and tested circuit board that contains all the components necessary to evaluate the performance of the MAX5885 16-bit parallel input, 200Msps, current-output, digital-to-analog converter (DAC). The EV kit operates with CMOS-compatible data inputs, a singleended clock input, and 3.3V power supplies for simple board operation. The MAX5885 EV kit can also be used to evaluate the MAX5884 (14 bit) and the MAX5883 (12 bit). Evaluates: MAX5883/MAX5884/MAX5885 MAX5885 Evaluation Kit Component Suppliers SUPPLIER PHONE FAX WEBSITE AVX 843-946-0238 843-626-3123 www.avxcorp.com Coilcraft 847-639-6400 847-639-1469 www.coilcraft.com IRC 361-992-7900 361-992-3377 www.irctt.com Kemet 864-963-6300 864-963-6322 www.kemet.com Mini-Circuits 718-934-4500 718-934-7092 www.minicircuits.com Panasonic 714-373-7366 714-737-7323 www.panasonic.com Samtec 800-726-8329 812-948-5047 www.samtec.com Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com TDK 847- 803-6100 847-390-4405 www.component.tdk.com Note: Please indicate that you are using the MAX5885 when contacting these component suppliers. Quick Start Recommended Equipment • Three 3.3V power supplies • Function generator with low phase noise and low jitter for clock input (e.g., HP 8662A) • 16-bit digital pattern generator for data inputs (e.g., Tektronix DG2020A) • Spectrum analyzer (e.g., HP 8560E) • Voltmeter The MAX5885 EV kit is a fully assembled and tested surface-mount board. Follow the steps below for board operation. Do not turn on power supplies or enable signal generators until all connections are completed. Procedure 1) Verify that a shunt is installed across pins 2 and 3 of jumper JU1 (DAC enabled). 2) Verify that shunts are not installed across jumpers JU2, JU4, and JU5 (DAC uses the 1.2V on-chip voltage reference). 3) Verify that a shunt is installed across jumper JU3. 4) Synchronize the digital pattern generator (DG2020A) with the clock function generator (HP 8662A). 5) Connect the clock function signal generator to the CLK SMA connectors on the EV kit. 6) Verify that the 16-bit digital pattern generator is programmed for valid CMOS output voltage levels. 2 7) Connect the digital signal generator output to the J1 input header connector on the EV kit board. The input header pins are labeled for proper connection with the digital pattern generator (i.e., connect bit 0 to the header pin labeled B0, connect bit 1 to the header pin labeled B1, etc.). 8) Connect the spectrum analyzer to the OUT SMA connector. 9) Connect a 3.3V power supply to the V_CLK pad. Connect the ground terminal of this supply to the CLKGND pad. 10) Connect a 3.3V power supply to the D_VDD pad. Connect the ground terminal of this supply to the DGND pad. 11) Connect a 3.3V power supply to the A_VDD pad. Connect the ground terminal of this supply to the AGND pad. 12) Turn on the three power supplies. 13) With a voltmeter, verify that 1.2V is measured at the V_REF PC board pad on the EV kit. 14) Enable the clock function generator (HP 8662A) and the digital pattern generator. Set the clock function generator output power to 10dBm and the frequency (fCLK) to less than or equal to 200MHz. 15) Use the spectrum analyzer to view the MAX5885 output spectrum or view the output waveform using an oscilloscope. Detailed Description The MAX5885 EV kit is designed to simplify the evaluation of the MAX5885 16-bit, 200Msps, current-output DAC. The MAX5885 operates with CMOS-compatible _______________________________________________________________________________________ MAX5885 Evaluation Kit (7dBm) is recommended or for a square wave, a minimum amplitude signal of 0.5VP-P is recommended. The MAX5885 EV kit provides a header connector to easily interface with a pattern generator, circuitry that converts the differential current output to a singleended voltage signal, and circuitry to convert a usersupplied single-ended clock signal to a differential clock signal required by the MAX5885. The EV kit circuit includes different options for supplying a reference voltage to the DAC. The EV kit can operate with a single 3.3V power supply but also supports the use of three separate 3.3V power supplies by dividing the circuit into digital, analog, and digital clock planes that improve dynamic performance. The MAX5885 requires a reference voltage to set the full-scale analog signal output voltage. The DAC contains a stable on-chip bandgap reference of 1.2V that is used by default. The internal reference can be overdriven by an external reference for gain control or to enhance accuracy and drift performance. Power Supplies The MAX5885 EV kit can operate from a single 3.3V power supply connected to the D_VDD, A_VDD, and V_CLK input power pads and their respective ground pads for simple board operation. However, three separate 3.3V power supplies are recommended for optimum dynamic performance. The EV kit board layout is divided into three sections: digital, analog, and digital clock. Using separate power supplies for each section reduces crosstalk noise and improves the integrity of the output signal. When using separate power supplies, connect each power supply across the D_VDD and DGND PC board pads (digital), across the V_CLK and CLKGND PC board pads (digital clock), and across the A_VDD and AGND PC board pads (analog) on the EV kit. CMOS Input Data The MAX5885 EV kit provides a 0.1in 2 x 20 header (J1) to interface a 16-bit CMOS pattern generator to the EV kit. The header data pins are labeled on the board with their appropriate data bit designation. Use the labels on the EV kit to match the data bits from the pattern generator to the corresponding data pins on header J1. Clock Signal The MAX5885 requires a differential clock input signal with minimal jitter. The EV kit circuit provides singleended to differential conversion circuitry. The user must supply a single-ended clock signal at the CLK SMA connector. The clock signal can be either a sine wave or a square wave. For a sine wave, a minimum amplitude of 1.5VP-P Reference Voltage Options The MAX5885 EV kit features three ways to provide a reference voltage to the DAC: internal, on-board external, and user-supplied external reference. Verify that a shunt is not connected across jumper JU5 to use the internal reference. The reference voltage can be measured at the V_REF pad on the EV kit. The EV kit circuit is designed with an on-board 1.25V temperature-stable external voltage reference source (U2, MAX6161) that can be used to overdrive the internal reference provided by the MAX5885. Install a shunt across jumpers JU4 and JU5 to use the on-board external reference. The user can also supply an external voltage reference in the 0.125V to 1.25V range by connecting a voltage source to the V_REF pad and removing the shunts across jumpers JU4 and JU5. See Table 1 to configure the shunts across jumpers JU4 and JU5 and select the source of the reference voltage. Full-Scale Current The MAX5885 requires an external resistor to set the full-scale output current. The MAX5885 EV kit full-scale current is set to 20mA with resistor R7. Replace R7 to adjust the full-scale output current. Refer to the Reference Architecture and Operation section in the MAX5885 data sheet to select different values for R7. Table 1. Reference Voltage Selection JU4 AND JU5 SHUNT POSITIONS Installed VOLTAGE REFERENCE MODE External 1.25V reference (U2) connected to MAX5885 REFIO pin Not installed MAX5885 internal 1.2V bandgap reference Not installed User-supplied voltage reference at the V_REF pad (0.125V to 1.25V) _______________________________________________________________________________________ 3 Evaluates: MAX5883/MAX5884/MAX5885 data inputs, a differential clock input signal, an internal 1.2V reference voltage, and a 3.3V power supply for simple board operation. Evaluates: MAX5883/MAX5884/MAX5885 MAX5885 Evaluation Kit Differential Output The MAX5885 complementary current outputs are terminated into differential 50Ω resistance to generate a voltage signal with an amplitude of 1VP-P differential. The positive and negative rails of the differential signal can be sampled at the IOUTP and IOUTN probe connectors. The differential signal is converted into a 50Ω singled-ended signal with transformers T1 and T2 and can be sampled at the OUT SMA connector. A shunt on jumper JU3 connects the center tap of the transformer T2 to AGND to enhance the dynamic performance of the MAX5885. The single-ended output signal from the transformer generates a -2dBm full-scale output power when terminated into 50Ω. A shunt should always be installed across jumper JU3 for optimum dynamic performance. Table 2. Jumper JU1 (Power-Down) SHUNT LOCATIONS MAX5885 FUNCTION 1 and 2 Power-down mode 2 and 3 Normal operation Table 3. Segment Shuffling Mode (Jumper JU2) SHUNT LOCATION SEL0 PIN (JU2) SEGMENTSHUFFLING MODE Installed Connected to D_VDD Enabled Not installed Connected to DGND with internal pulldown resistor Disabled Power-Down The MAX5885 can be powered down or up by reconfiguring jumper JU1. In power-down mode, the total power dissipation of the DAC is reduced to less than 1mW. See Table 2 for the jumper JU1 configuration. Segment Shuffling The segment shuffling function on the MAX5885 improves the dynamic performance at the cost of a slight increase in the DAC’s noise floor. The MAX5885 EV kit provides jumper JU2, which allows the user to enable and disable the segment-shuffling function. See Table 3 to configure jumper JU2. XOR Input The MAX5885 provides an XOR input pin that may be used to troubleshoot possible spurious or harmonic distortion degradation due to digital data feedthrough on the PC board. The XOR pin can be accessed at pin 7 of header J1. Connect an external device to this pin to assert a logic signal on the XOR pin. Refer to the XOR Function (XOR ) section in the MAX5885 data sheet for further details. 4 Evaluating the MAX5884 or MAX5883 The MAX5885 EV kit can be used to evaluate the MAX5884 or MAX5883. The MAX5884 is a 14-bit and the MAX5883 is a 12-bit DAC. Except for the input pins, these DACs are pin-for-pin compatible with the MAX5885. Replace the MAX5885 (U1) with the MAX5884 or the MAX5883 and refer to the respective data sheet to compare the differences in input pins and how to modify the connections between the pattern generator and the EV kit’s J1 input connector. Board Layout The MAX5885 EV kit is a four-layer board design optimized for high-speed signals. All high-speed signal lines are routed through 50Ω impedance-matched transmission lines. The length of these 50Ω transmission lines is matched to within 40 mils (1mm) to minimize layout-dependent data skew. The board layout separates the digital, analog, and digital clock sections of the circuit for optimum performance. _______________________________________________________________________________________ _______________________________________________________________________________________ TP2 3 1 1 AVDD JU4 4 CLKGND C12 0.1µF C20 47µF 6.3V L2 MAX6161 U2 C24 OPEN JU1 VCLK C9 0.1µF JU5 VREF C22 1µF C3 0.1µF AVDD 12 11 10 8 9 7 6 5 4 3 2 1 13 REFIO AGND AVDD PD CLKGND VCLK CLKN CLKP CLKGND VCLK B2 48 R33 OPEN 14 47 15 DACREF B3 R12 0Ω J1–15 J1–26 R7 2kΩ 1% FSADJ R11 0Ω J1–13 J1–28 XOR B0 B1 R32 OPEN C2 0.1µF CLKGND C8 0.1µF VCLK VCLK C16 1µF CLKGND TP5 C21 10µF 10V 3 1 2 AVDD R26 0Ω R25 0Ω C23 OPEN R29 OPEN R30 OPEN R31 OPEN C15 10µF 10V DVDD N.C. 8 7 N.C. 6 OUT 5 N.C. R8 0Ω R9 0Ω R10 0Ω R28 24.9Ω C11 1% 0.1µF R27 24.9Ω 1% GND N.C. IN N.C. CLKGND 4 3 2 1 CLKGND T3 6 J1–1 J1–3 J1–5 J1–7 J1–9 J1–11 CLKGND V_CLK C10 0.1µF CLKGND CLKGND CLKGND 2 CLK J1–40 J1–38 J1–36 J1–34 J1–32 J1–30 DGND C14 47µF 6.3V L1 JU3 16 B4 46 N.C. R34 OPEN R35 OPEN C13 0.1µF IOUTN 17 AGND R13 0Ω J1–17 J1–24 R6 SHORT R1 49.9Ω 0.1% B5 45 1 1 6 5 C1 OPEN 6 18 2 TP3 3 4 19 R4 OPEN T1 DVDD 43 4 T2 3 U1 42 DGND TP1 1 2 OUT R5 SHORT R37 OPEN IOUTP 20 AGND MAX5885 R2 49.9Ω 0.1% IOUTP B6 44 C7 0.1µF R15 0Ω DVDD J1–21 J1–20 R3 100Ω 1% R36 OPEN IOUTN R14 0Ω J1–19 J1–22 21 AVDD B7 41 B8 40 R39 OPEN 22 AGND R17 0Ω J1–25 J1–16 C4 0.1µF R38 OPEN AVDD R16 0Ω J1–23 J1–18 AVDD B9 39 R40 OPEN 23 AVDD R18 0Ω J1–27 J1–14 C5 0.1µF B10 38 R19 0Ω J1–29 J1–12 24 N.C. N.C. N.C. N.C. N.C. SEL0 DGND DVDD B15 B14 B13 B12 B11 37 AGND R41 OPEN 25 26 27 28 29 30 32 31 33 34 35 36 R20 0Ω J1–31 J1–10 R45 OPEN R44 OPEN C27 1µF R24 0Ω R23 0Ω R22 0Ω R21 0Ω R43 OPEN R42 OPEN DVDD C6 0.1µF JU2 DVDD TP4 C19 1µF C26 10µF 10V C18 10µF 10V VREF AVDD L4 L3 C25 47µF 6.3V J1–39 J1–37 J1–35 J1–33 C17 47µF 6.3V AGND V_REF J1–2 J1–4 J1–6 J1–8 AGND A_VDD Evaluates: MAX5883/MAX5884/MAX5885 D_VDD MAX5885 Evaluation Kit Figure 1. MAX5885 EV Kit Schematic 5 Evaluates: MAX5883/MAX5884/MAX5885 MAX5885 Evaluation Kit Figure 2. MAX5885 EV Kit Component Placement Guide—Component Side 6 _______________________________________________________________________________________ MAX5885 Evaluation Kit Evaluates: MAX5883/MAX5884/MAX5885 Figure 3. MAX5885 EV Kit PC Board Layout—Component Side _______________________________________________________________________________________ 7 Evaluates: MAX5883/MAX5884/MAX5885 MAX5885 Evaluation Kit Figure 4. MAX5885 EV Kit PC Board Layout—Ground Plane 8 _______________________________________________________________________________________ MAX5885 Evaluation Kit Evaluates: MAX5883/MAX5884/MAX5885 Figure 5. MAX5885 EV Kit PC Board Layout—Power Plane _______________________________________________________________________________________ 9 Evaluates: MAX5885/MAX5884/MAX5883 MAX5885 Evaluation Kit Figure 6. MAX5885 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. 10 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.