a ANALOG RETURN D1 D3 D4 TTL DRIVE LOGIC D5 D6 D7 D8 D9 The AD9732 is a 10-bit, 200 MSPS, bipolar D/A converter that is optimized to provide high dynamic performance, yet offers lower power dissipation and a more economical price than previous high speed DAC solutions. The AD9732 was primarily designed for demanding communications systems applications where maximum spurious-free dynamic range (SFDR) is required at high throughput rates. The proliferation of digital communications into base station and high volume subscriber-end markets has created a demand for high performance bipolar DACs delivered at CMOS associated levels of power dissipation and cost. The AD9732 is the answer to that demand. Optimized for direct digital synthesis (DDS) and digital modulator waveform reconstruction, the AD9732 provides >50 dB of wideband harmonic suppression over the dc to 80 MHz analog output bandwidth. This signal bandwidth addresses the transmit IOUT IOUT D10 REFIN CLOCK INTERNAL VOLTAGE REFERENCE GENERAL DESCRIPTION REGISTER D2 SWITCH NETWORK APPLICATIONS Digital Communications Direct Digital Synthesis Waveform Reconstruction High Speed Imaging FUNCTIONAL BLOCK DIAGRAM DECODERS AND DRIVERS FEATURES 200 MSPS Throughput Rate 3.3 V PECL Digital Input 65 dB SFDR @ 2 MHz A OUT, 200 MSPS/54 dB @ 40 MHz A OUT, 200 MSPS Low Power: 305 mW Fast Settling: 5 ns to 1/2 LSB Low Glitch Energy: 6 pVs Internal Reference 28-Lead SSOP Packaging 10-Bit, 200 MSPS D/A Converter AD9732 CONTROL AMP AD9732 RSET REFOUT CONTROL AMP IN CONTROL AMP OUT DIGITAL +VS spectrum in many of the emerging digital communications applications where signal purity is critical. Narrowband (± 1 MHz window), the AD9732 provides an SFDR of greater than 75 dB. This level of wideband and narrowband ac performance, coupled with its 200 MSPS throughput rate, enables the AD9732 to present outstanding value in the high speed DAC function. The AD9732 is packaged in a 28-lead SSOP and is specified to operate over the extended industrial temperature range of –40°C to +85°C. Digital inputs and clock are positive-ECL compatible. REV. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 1999 AD9732–SPECIFICATIONS ELECTRICAL CHARACTERISTICS (+V S Parameter Temp Test Level Min AD9732BRS Typ THROUGHPUT RATE +25°C IV 165 200 MHz 10 Bits = +5 V, ENCODE = 125 MSPS, RSET = 1.95 k⍀ (for 20 mA I OUT) unless otherwise noted) RESOLUTION DC ACCURACY Differential Nonlinearity Max Units +25°C Full +25°C Full I VI I VI 0.25 0.36 0.6 0.7 1 1 1.5 1.5 LSB LSB LSB LSB +25°C Full +25°C Full I VI I VI V 35 40 2.5 2.5 0.04 70 100 5 5 µA µA % FS % FS µA/°C REFERENCE/CONTROL AMP Internal Reference Voltage2 Internal Reference Voltage Drift Internal Reference Output Current3 Amplifier Input Impedance Amplifier Bandwidth +25°C Full Full +25°C +25°C I IV VI I I 3.75 150 3.85 50 2.5 V µV/°C µA kΩ MHz REFERENCE INPUT4 Reference Input Impedance Reference Multiplying Bandwidth5 +25°C +25°C V V 4.6 75 kΩ MHz OUTPUT PERFORMANCE Output Current4, 6 Output Compliance Output Resistance Output Capacitance Voltage Settling Time to 1/2 LSB (tST)7 Propagation Delay (tPD)8 Glitch Impulse9 Output Slew Rate10 Output Rise Time10 Output Fall Time10 Full Full +25°C +25°C +25°C +25°C Full Full Full Full V IV V V V V V V V V Full Full +25°C +25°C Full +25°C Full +25°C Full +25°C +25°C VI VI I I V IV IV IV IV IV IV +25°C Full +25°C Full +25°C Full +25°C I VI I VI V V V Integral Nonlinearity INITIAL OFFSET ERROR Zero-Scale Offset Error Full-Scale Gain Error1 Offset Drift Coefficient DIGITAL INPUTS Logic “1” Voltage Logic “0” Voltage Logic “1” Current Logic “0” Current Input Capacitance Minimum Data Setup Time (tS )11 Minimum Data Hold Time (tH)12 Clock Pulsewidth Low (pwMIN) Clock Pulsewidth High (pwMAX) POWER SUPPLY13 Digital +V Supply Current Analog +V Supply Current Power Dissipation14 Power Supply Rejection Ratio (PSRR) –2– 3.65 –50 +500 20 2 5.75 240 5 4.75 2.7 5.9 450 1 1 2.4 –1 1.7 0.01 2 0.7 1 0.7 1 1.6 10 1 1.5 1.5 1.5 1.5 2 2 15 10 10 10 25 20 305 350 200 35 40 30 30 mA V Ω pF ns ns pVs V/µs ns ns V V µA µA pF ns ns ns ns ns ns mA mA mA mA mW mW µA/V REV. A AD9732 Temp Test Level SFDR PERFORMANCE (Wideband) 2 MHz AOUT 10 MHz AOUT 20 MHz AOUT 40 MHz AOUT 2 MHz AOUT (Clock = 165 MHz) 10 MHz AOUT (Clock = 165 MHz) 20 MHz AOUT (Clock = 165 MHz) 40 MHz AOUT (Clock = 165 MHz) 65 MHz AOUT (Clock = 165 MHz) 65 MHz AOUT (Clock = 200 MHz) 80 MHz AOUT (Clock = 200 MHz) +25°C +25°C +25°C +25°C +25°C +25°C +25°C +25°C +25°C +25°C +25°C V V V V V V V V V V V 66 63 57 52 63 62 56 51 48 45 43 dB dB dB dB dB dB dB dB dB dB dB SFDR PERFORMANCE (Narrowband)15 2 MHz; 2 MHz Span 25 MHz; 2 MHz Span 10 MHz; 5 MHz Span (Clock = 200 MHz) +25°C +25°C +25°C V V V 77 65 70 dB dB dB +25°C V 69 dB +25°C V 61 dB Parameter Min AD9732BRS Typ Max Units 15 INTERMODULATION DISTORTION16 F1 = 800 kHz, F2 = 900 kHz to Nyquist F1 = 800 kHz, F2 = 900 kHz, Narrowband (2 MHz) NOTES 1 Measured as an error in ratio of full-scale current to current through R SET (640 µA nominal); ratio is nominally 32. DAC load is virtual ground. 2 Internal reference voltage is tested under load conditions specified in Internal Reference Output Current specification. 3 Internal reference output current defines load conditions applied during Internal Reference Voltage test. 4 Full-scale current variations among devices are higher when driving REFERENCE IN directly. 5 Frequency at which a 3 dB change in output of DAC is observed; R L = 50 Ω; 100 mV modulation at midscale. 6 Based on I FS = 32 ([CONTROL AMP IN – (+VS )]/RSET) when using internal control amplifier. DAC load is virtual ground. 7 Measured as voltage settling at midscale transition to 0.1%; R L = 50 Ω. 8 Measured from 50% point of rising edge of CLOCK signal to 1/2 LSB change in output signal. 9 Peak glitch impulse is measured as the largest area under a single positive or negative transient. 10 Measured with R L = 50 Ω and DAC operating in latched mode. 11 Data must remain stable for a specified time prior to rising edge of CLOCK. 12 Data must remain stable for a specified time after rising edge of CLOCK. 13 Supply voltages should remain stable with ±5% for nominal operation. 14 Power dissipation calculation includes current through a 50 Ω load. 15 SFDR is defined as the difference in signal energy between the full-scale fundamental signal and worst case spurious frequencies in the output spectrum window. The frequency span dc to Nyquist unless otherwise noted. 16 Intermodulation distortion is the measure of the sum and difference products produced when a two-tone input is driven into the DAC. The distortion products created will manifest themselves at sum and difference frequencies of the two tones. Specifications subject to change without notice. EXPLANATION OF TEST LEVELS Test Level IV Parameter is guaranteed by design and characterization testing. I V Parameter is a typical value only. 100% production tested. II 100% production tested at +25°C and sample tested at specified temperatures. III Sample tested only. VI 100% production tested at +25°C; guaranteed by design and characterization testing for industrial temperature range. ORDERING GUIDE REV. A Model Temperature Range Package Description Package Option AD9732BRS AD9732/PCB –40°C to +85°C +25°C 28-Lead Small Outline (SSOP) Evaluation Board RS-28 –3– AD9732 ABSOLUTE MAXIMUM RATINGS* PIN CONFIGURATION Analog Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +VS +VS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +6 V Digital Inputs . . . . . . . . . . . . . . . . . . . . . . . . . –0.7 V to +VS Analog Output Current . . . . . . . . . . . . . . . . . . . . . . . . 30 mA Control Amplifier Input Voltage Range . . . . . . . . . 0 V to +VS Reference Input Voltage Range . . . . . . . . . . . . . . . 0 V to +VS Internal Reference Output Current . . . . . . . . . . . . . . . 500 µA Control Amplifier Output Current . . . . . . . . . . . . . . ± 2.5 mA Operating Temperature . . . . . . . . . . . . . . . . . –40°C to +85°C Storage Temperature . . . . . . . . . . . . . . . . . . –65°C to +150°C Maximum Junction Temperature . . . . . . . . . . . . . . . +175°C Lead Temperature (10 sec) Soldering . . . . . . . . . . . . +300°C D9 (MSB) 1 28 DIGITAL +VS D8 2 27 GND D7 3 26 CONTROL AMP IN D6 4 25 REF OUT D5 5 24 CONTROL AMP OUT D4 6 23 REF IN AD9732 D3 7 TOP VIEW 22 GND D2 8 (Not to Scale) 21 IOUTB *Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions outside of those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum ratings for extended periods may affect device reliability. D1 9 20 IOUT D0 (LSB) 10 19 ANALOG RETURN CLOCK 11 18 ANALOG +VS NC 12 17 RSET NC 13 16 GND DIGITAL +VS 14 15 DIGITAL +VS NC = NO CONNECT PIN FUNCTION DESCRIPTIONS Pin Number Name Function 1 2–9 10 11 12, 13 14, 15, 28 16, 22, 27 18 17 D9 (MSB) D8–D1 D0 (LSB) CLOCK NC DIGITAL +VS GND ANALOG +VS RSET 19 ANALOG RETURN 20 IOUT 21 IOUTB 23 REF IN 24 CONTROL AMP OUT 25 REF OUT 26 CONTROL AMP IN Most significant data bit of digital input word. Eight bits of 10-bit digital input word. Least significant data bit of digital input word. TTL-compatible edge-triggered latch enable signal for on-board registers. No internal connection to this pin. Recommend tie to ground. +5 V supply voltage for digital circuitry. Converter Ground. +5 V supply voltage for analog circuitry. Connection for external reference set resistor; nominal 1.96 kΩ. Full-scale output current = 32 [Control Amp + VS] (Reset). Analog Return. This point and the reference side of the DAC load resistors should be connected to the same potential (Analog +VS). Analog current output; full-scale current occurs with a digital word input of all “1s” with external load resistor, output voltage = IOUT (RLOAD储RINTERNAL ). RINTERNAL is nominally 240 Ω. Complementary analog current output; full-scale current occurs with a digital word input of all “0s.” Normally connected to CONTROL AMP OUT (Pin 24). Direct line to DAC current source network. Voltage changes (noise) at this point have a direct effect on the fullscale output current of the DAC. Full-scale current output = 32 (CONTROL AMP IN/ RSET) when using internal amplifier. DAC load is virtual ground. Normally connected to REF IN (Pin 23). Output of internal control amplifier, which provides a reference for the current switch network. Normally connected to CONTROL AMP IN (Pin 26). Internal voltage reference, nominally 3.75 V. Normally connected to REF OUT (Pin 25) if not connected to external reference. CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD9732 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. –4– WARNING! ESD SENSITIVE DEVICE REV. A AD9732 pwMIN pwMAX CLOCK tS tH CODE 1 DATA DATA CODE 2 DATA CODE 3 DATA CODE 4 DATA CODE 2 ANALOG OUTPUT CODE 4 CODE 1 CODE 3 a. DETAIL OF SETTLING TIME GLITCH AREA = 1/2 HEIGHT 3 WIDTH H CLOCK SPECIFIED ERROR BAND tPD W ANALOG OUTPUT tST b. c. Figure 1. Timing Diagrams REV. A –5– AD9732 75 55 70 65 50 SFDR – dB SFDR – dB 60 55 50 45 45 40 35 30 0 10 20 30 40 50 60 AOUT – MHz 70 80 90 40 20 100 18 Figure 2. Narrowband SFDR (Clock = 200 MHz) vs. AOUT Frequency 16 14 12 10 IOUT – mA 8 6 2 4 Figure 5. SFDR vs. IOUT 90 56 54 80 52 50 SFDR – dB SFDR – dB 70 60 50 48 46 44 40 42 30 5 10 15 20 25 30 35 40 AOUT – MHz 45 50 55 40 60 Figure 3. Narrowband SFDR (Clock = 125 MHz) vs. AOUT Frequency 25 45 65 85 105 125 CLOCK – MHz 145 165 185 205 Figure 6. SFDR vs. Clock for f CLK/AOUT = 3.125 65 0.4 60 0.3 0.2 55 0.1 50 LSB SFDR – dB 5 0 45 –0.1 40 –0.2 35 –0.3 30 10 20 30 40 50 60 AOUT – MHz 70 80 –0.4 90 Figure 4. Wideband SFDR (200 MHz Clock) vs. A OUT Figure 7. Typical Differential Nonlinearity Performance (DNL) –6– REV. A AD9732 0.6 0 1 ENCODE = 125MHz AOUT = 20MHz SPAN = 62.5MHz SFDR = 57dB –10 0.4 –20 –30 0.2 LSB –40 0 –50 –60 1 –0.2 –70 –80 –0.4 –90 –0.6 –100 START 0Hz Figure 8. Typical Integral Nonlinearity Performance (INL) 0 ENCODE = 125MHz AOUT = 2MHz SPAN = 62.5MHz SFDR = 66dB –20 –10 –20 –30 –30 –40 –40 –50 –50 –60 –60 1 –80 –90 –90 –100 START 0Hz 6.25MHz/ 1 –100 STOP 62.5MHz START 0Hz Figure 9. Wideband SFDR 2 MHz A OUT; 125 MHz Clock ENCODE = 125MHz AOUT = 10MHz SPAN = 62.5MHz SFDR = 63dB –20 6.25MHz/ 1 ENCODE = 200MHz AOUT = 40MHz SPAN = 100MHz SFDR = 54dB –10 –20 –30 –30 –40 –40 –50 –50 –60 1 –60 1 –70 STOP 62.5MHz Figure 12. Wideband SFDR 40 MHz AOUT; 125 MHz Clock 0 1 –10 –70 –80 –80 –90 –90 –100 –100 START 0Hz 6.25MHz/ STOP 62.5MHz START 0Hz Figure 10. Wideband SFDR 10 MHz A OUT; 125 MHz Clock REV. A 1 ENCODE = 125MHz AOUT = 40MHz SPAN = 62.5MHz SFDR = 52dB –70 –80 0 STOP 62.5MHz Figure 11. Wideband SFDR 20 MHz AOUT; 125 MHz Clock 0 1 –10 –70 6.25MHz/ 10MHz/ STOP 100MHz Figure 13. Wideband SFDR 40 MHz AOUT; 200 MHz Clock –7– AD9732 1 0 –10 –20 0 1 ENCODE = 200MHz AOUT = 65MHz SPAN = 200MHz SFDR = 45dB ENCODE = 125MHz AOUT1 = 800kHz AOUT2 = 900kHz SPAN = 2MHz IMD = 61dB –10 –20 –30 –30 –40 –40 1 –50 –50 –60 –60 –70 –70 –80 –80 –90 –90 –100 START 0Hz 10MHz/ 1 –100 STOP 100MHz START 0Hz Figure 14. Wideband SFDR 65 MHz A OUT; 200 MHz Clock 200MHz/ STOP 2MHz Figure 16. Wideband Intermodulation Distortion F1 = 800 kHz; F2 = 900 kHz; 125 MHz Clock; Span = 2 MHz 1 0 –10 –20 0 1 ENCODE = 200MHz AOUT = 80MHz SPAN = 100MHz SFDR = 43dB ENCODE = 125MHz AOUT1 = 800kHz AOUT2 = 900kHz SPAN = 62.5MHz IMD = 69dB –10 –20 –30 –30 –40 –40 1 –50 –50 –60 –60 –70 –70 –80 –80 –90 –90 1 –100 –100 START 0Hz 10MHz/ START 0Hz STOP 100MHz Figure 15. Wideband SFDR 80 MHz A OUT; 200 MHz Clock 6.25MHz/ STOP 62.5MHz Figure 17. Wideband Intermodulation Distortion F1 = 800 kHz; F2 = 900 kHz; 125 MHz Clock; Span = 62.5 MHz –8– REV. A AD9732 However, it should be noted that output settling time, for changes in the digital word, will be degraded. APPLICATION NOTES THEORY OF OPERATION The AD9732 high speed digital-to-analog converter utilizes most significant bit decoding and segmentation techniques to reduce glitch impulse and deliver high dynamic performance on lower power consumption than previous bipolar DAC technologies. +VS RSET RSET AD9732 The design is based on four main subsections: the decode/driver circuits, the edge-triggered data register, the switch network and the control amplifier. An internal bandgap reference is included to allow operation of the device with minimum external support components. 3.8V TO 4.4V 2.5MHz TYPICAL CONTROL AMP IN RT CONTROL AMP OUT Digital Inputs/Timing REFERENCE IN The AD9732 has PECL high speed single-ended inputs for data inputs and clock. The switching threshold is +2.0 V. 0.1mF In the decode/driver section, the three MSBs are decoded to seven “thermometer code” lines. An equalizing delay is included for the seven least significant bits and the clock signals. This delay minimizes data skew and data setup-and-hold times at the register inputs. Figure 18. Lower Frequency Multiplying Circuit The REFERENCE IN pin can also be driven directly for wider bandwidth multiplying operation. The analog signal for this mode of operation must have a signal swing in the range of 0.95 V to 1.9 V. This can be implemented by capacitively coupling into REFERENCE IN a signal with a dc bias of 1.9 V (IOUT = 22.5 mA) to 0.95 V (IOUT = 3 mA), as shown in Figure 19, or by dividing REFERENCE IN with a low impedance op amp whose signal swing is limited to the stated range. The on-board register is rising-edge triggered and should be used to synchronize data to the current switches by applying a pulse with proper data setup-and-hold times as shown in the timing diagram. Although the AD9732 is designed to provide isolation of the digital inputs to the analog output, some coupling of digital transitions is inevitable. Digital feedthrough can be minimized by forming a low-pass filter at the digital input by using a resistor in series with the capacitance of each digital input. This common high speed DAC application technique has the effect of isolating digital input noise from the analog output. AD9732 APPROX 1.4V REFERENCE IN References The internal bandgap reference, control amplifier and reference input are pinned out to provide maximum user flexibility in configuring the reference circuitry for the AD9732. When using the internal reference, REF OUT (Pin 25) should be connected to CONTROL AMP IN (Pin 26). CONTROL AMP OUT (Pin 24) should be connected to REF IN (Pin 23). A 0.1 µF ceramic capacitor connected from Pin 23 to GND improves settling time by decoupling switching noise from the current sink baseline. A reference current cell provides feedback to the control amplifier by sinking current through RSET (Pin 17). Figure 19. Wideband Multiplying Circuit Analog Output The switch network provides complementary current outputs IOUT and IOUTB. The design of the AD9732 is based on statistical current source matching, which provides a 10-bit linearity without trim. Current is steered to either IOUT or IOUTB in proportion to the digital input word. The sum of the two currents is always equal to the full-scale output current. The current can be converted to a voltage by resistive loading as shown in Figure 20. Both IOUT and IOUTB should be equally loaded for best overall performance. The voltage that is developed is the product of the output current and the value of the load resistor. Full-scale current is determined by CONTROL AMP IN and RSET according to the following equation: IOUT(FS) = 32 ([CONTROL AMP IN – (+VS)]/RSET) The internal reference is nominally –1.25 V (referenced to Analog +VS), with a tolerance of ± 8% and typical drift over temperature of 150 ppm/°C. If greater accuracy or temperature stability is required, an external reference can be used. The AD589 reference features 10 ppm/°C drift over the 0°C to +70°C temperature range. EVALUATION BOARD The performance characteristics of the AD9732 make it ideally suited for direct digital synthesis (DDS) and other waveform synthesis applications. The AD9732 evaluation board provides a platform for analyzing performance under optimum layout conditions. The AD9732 also provides a reference for high speed circuit board layout techniques. Two modes of multiplying operation are possible with the AD9732. Signals with bandwidths up to 2.5 MHz and input swings from 3.8 V to 4.4 V can be applied to the CONTROL AMP IN pin as shown in Figure 18. Because the control amplifier is internally compensated, the 0.1 µF capacitor discussed above can be reduced to maximize the multiplying bandwidth. REV. A +VS –9– –10– 7 OSC_OUT R14 390V CLKB TB4 TB1 4 3 2 1 +5V E25 C9 10mF C2 0.1mF E10 E12 E14 E16 E18 E20 E22 E24 E26 C3 0.1mF NOTE: SERIES 64.9V RESISTORS CAN BE BYPASSED BY JUMPING E7 TO E8, ECT. R12 64.9V R11 64.9V R10 64.9V R9 64.9V R8 64.9V R4 64.9V R3 64.9V R2 64.9V E8 1 CMOS CLOCK OSCILLATOR GND CR1 R17 1N914 180V 8 E23 1 +5V E21 1 R13 780V E19 1 1 +5V E17 1 1 14 E15 1 1 IN +V 1 Y1 1 1 1 NO_CONN 1 1 1 1 SW41 1 1 R6 50V CLK E13 1 E6 2 4 6 8 10 12 14 16 18 20 E11 R1 64.9V R18 64.9V 1 E5 1 3 5 7 9 11 13 15 17 19 H1 E5 1 E4 1 E2 SW1 E7 1 E3 E1 1 BNC J1 1 CLKB 5 = GND PIN FOR EXTERNAL CLOCK ADD 50V TERMINATION FOR EXTERNAL CLOCK R5 50V 4 TO 6 BNC EXTERNAL PECL CLOCK (50V) ON BOARD XTAL OSCILLATOR 3 = INPUT PIN FOR EXTERNAL CLOCK 2 TO 4 1 TO 3 CLOCK MATRIX DESCRIPTION CONNECTIONS 1 C37DRPF P1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 SW1 C4 0.1mF CLK C5 0.1mF R7 1960V 1 2 3 4 5 6 7 8 9 10 11 12 13 17 C6 0.1mF C7 0.1mF +5V: 14, 15, 18, 19, 28 ANALOG GND 22 DIGITAL GND 16, 27 D9 (MSB) IOUT D8 D7 I_OUT D6 U1 D5 D4 AD9732 D3 REFOUT D2 D1 C_AMP_IN D0 (LSB) CLK NC1 C_AMP_OUT NC2 RSET REF_IN 23 24 26 25 20 21 SINGLE-ENDED RESISTIVE TERMINATED 29 TO 32 31 TO 30 C8 10mF R16 25V E30 1 E32 1 E28 1 + C1 0.1mF E31 1 E29 1 E27 1 SW2 DIFFERENTIAL TRANSFORMER COUPLED TERMINATION OUTPUT DESCRIPTION 27 TO 29 30 TO 28 SW2 T1 6 4 R15 50V C10 0.1mF C11 0.1mF T1–1T 1 2 3 +5V +5V DAC_OUT (SINGLE ENDED) J2 OUT TO 50V LOAD J3 OUT TO 50V LOAD DAC_OUT (DIFFERENTIAL) AD9732 Figure 20. Evaluation Board REV. A AD9732 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). C3365a–0–4/99 28-Lead SSOP (RS-28) 28 15 1 14 0.078 (1.98) PIN 1 0.068 (1.73) 0.07 (1.79) 0.066 (1.67) 88 0.015 (0.38) SEATING 0.009 (0.229) 08 0.010 (0.25) PLANE 0.005 (0.127) 0.03 (0.762) 0.022 (0.558) PRINTED IN U.S.A. 0.008 (0.203) 0.0256 (0.65) 0.002 (0.050) BSC 0.212 (5.38) 0.205 (5.21) 0.311 (7.9) 0.301 (7.64) 0.407 (10.34) 0.397 (10.08) REV. A –11–