12-Bit 200 kSPS a Complete Sampling ADC AD678 FUNCTIONAL BLOCK DIAGRAM FEATURES AC and DC Characterized and Specified SC OE EOCEN SYNC 12/8 EOC CS (K, B and T Grades) AD678 200k Conversions per Second 1 MHz Full Power Bandwidth CONTROL LOGIC VOLTAGE REF 500 kHz Full Linear Bandwidth OUT REF. DB11 12 72 dB S/N+D (K, B, T Grades) REF DB2 IN OUTPUT Twos Complement Data Format (Bipolar Mode) DB1 12 REGISTER (R/L) Straight Binary Data Format (Unipolar Mode) 12-BIT D/A CONVERSION CONVERTER LOGIC DB0 10 M Input Impedance (HBE) 8-Bit or 16-Bit Bus Interface BIPOFF V CC 4 On-Board Reference and Clock V EE 4-BIT FLASH GAIN SAMPLE/ 10 V Unipolar or Bipolar Input Range A/D AIN V STAGE DD HOLD CONVERTER Commercial, Industrial and Military Temperature DGND AGND Range Grades MIL-STD-883 Compliant Versions Available PRODUCT DESCRIPTION PRODUCT HIGHLIGHTS The AD678 is a complete, multipurpose 12-bit monolithic 1. COMPLETE INTEGRATION: The AD678 minimizes ex- analog-to-digital converter, consisting of a sample-hold ampli- ternal component requirements by combining a high speed fier (SHA), a microprocessor compatible bus interface, a voltage sample-hold amplifier (SHA), ADC, 5 V reference, clock and reference and clock generation circuitry. digital interface on a single chip. This provides a fully speci- fied sampling A/D function unattainable with discrete designs. The AD678 is specified for ac (or dynamic) parameters such as S/N+D ratio, THD and IMD which are important in signal 2. SPECIFICATIONS: The AD678K, B and T grades provide processing applications. In addition, the AD678K, B and T fully specified and tested ac and dc parameters. The AD678J, grades are fully specified for dc parameters which are important A and S grades are specified and tested for ac parameters dc in measurement applications. accuracy specifications are shown as typicals. DC specifica- tions (such as INL, gain and offset) are important in control The AD678 offers a choice of digital interface formats the 12 and measurement applications. AC specifications (such as data bits can be accessed by a 16-bit bus in a single read opera- S/N+D ratio, THD and IMD) are of value in signal process- tion or by an 8-bit bus in two read operations (8+4), with right ing applications. or left justification. Data format is straight binary for unipolar mode and twos complement binary for bipolar mode. The input 3. EASE OF USE: The pinout is designed for easy board lay- has a full-scale range of 10 V with a full power bandwidth of out, and the choice of single or two read cycle output pro- 1 MHz and a full linear bandwidth of 500 kHz. High input im- vides compatibility with 16- or 8-bit buses. Factory trimming pedance (10 M ) allows direct connection to unbuffered eliminates the need for calibration modes or external trim- sources without signal degradation. ming to achieve rated performance. This product is fabricated on Analog Devices BiMOS process, 4. RELIABILITY: The AD678 utilizes Analog Devices mono- combining low power CMOS logic with high precision, low lithic BiMOS technology. This ensures long-term reliability noise bipolar circuits laser-trimmed thin-film resistors provide compared to multichip and hybrid designs. high accuracy. The converter utilizes a recursive subranging 5. UPGRADE PATH: The AD678 provides the same pinout as algorithm which includes error correction and flash converter the 14-bit, 128 kSPS AD679 ADC. circuitry to achieve high speed and resolution. 6. The AD678 is available in versions compliant with MIL- The AD678 operates from +5 V and 12 V supplies and dissipates STD-883. Refer to the Analog Devices Military Products 560 mW (typ). The AD678 is available in 28-lead plastic DIP, Databook or current AD678/883B data sheet for detailed ceramic DIP, and 44-lead J-leaded ceramic surface mount packages. specifications. Screening to MIL-STD-883C Class B is also available. REV. C Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. use, nor for any infringements of patents or other rights of third parties Tel: 781/329-4700 World Wide Web Site: AD678SPECIFICATIONS (T to T , V = +12 V 5%, V = 12 V 5%, V = +5 V 10%, f = 200 kSPS, MIN MAX CC EE DD SAMPLE 1 AC SPECIFICATIONS f = 10.06 kHz unless otherwise noted) lN AD678J/A/S AD678K/B/T Parameter Min Typ Max Min Typ Max Units 2 SIGNAL-TO-NOISE AND DISTORTION (S/N+D) RATIO 0.5 dB Input (Referred to 0 dB Input) 70 71 71 73 dB 20 dB Input (Referred to 20 dB Input) 51 53 dB 60 dB Input (Referred to 60 dB Input) 11 13 dB 3 TOTAL HARMONIC DISTORTION (THD) 88 80 88 80 dB 0.004 0.010 0.004 0.010 % PEAK SPURIOUS OR PEAK HARMONIC COMPONENT 87 80 87 80 dB FULL POWER BANDWIDTH 1 1 MHz FULL LINEAR BANDWIDTH 500 500 kHz 4 INTERMODULATION DISTORTION (IMD) 2nd Order Products 85 80 85 80 dB 3rd Order Products 90 80 90 80 dB NOTES 1 f amplitude = 0.5 dB (9.44 V p-p) bipolar mode full scale unless otherwise indicated. All measurements referred to a 0 dB (9.997 V p-p) input signal unless IN otherwise indicated. 2 See Figures 13 and 14 for higher frequencies and other input amplitudes. 3 See Figure 12. 4 f = 9.08 kHz, f = 9.58 kHz, with f = 200 kSPS. See Definition of Specifications section and Figure 16. A B SAMPLE Specifications subject to change without notice. DIGITAL SPECIFICATIONS (All device types T to T , V = +12 V 5%, V = 12 V 5%, V = +5 V 10%) MIN MAX CC EE DD Parameter Test Conditions Min Max Units LOGIC INPUTS V High Level Input Voltage 2.0 V V IH DD V Low Level Input Voltage 0 0.8 V IL I High Level Input Current V = V 10 +10 A IH IN DD I Low Level Input Current V = 0 V 10 +10 A IL IN C Input Capacitance 10 pF IN LOGIC OUTPUTS V High Level Output Voltage I = 0.1 mA 4.0 V OH OH I = 0.5 mA 2.4 V OH V Low Level Output Voltage I = 1.6 mA 0.4 V OL OL I High Z Leakage Current V = 0 or V 10 +10 A OZ IN DD C High Z Output Capacitance 10 pF OZ Specifications subject to change without notice. 2 REV. C