ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters PRODUCT OVERVIEW The ADS-927 is a high-performance, 14-bit, Requiring ±15V (or ±12V) and +5V supplies, 1MHz sampling A/D converter. This device samples the ADS-927 dissipates only 1.95W (1.65W for input signals up to Nyquist frequencies with no ±12V), maximum. The unit is offered with a bipolar missing codes. The ADS-927 features outstanding input (–5V to +5V). Models are available for use dynamic performance including a THD of –80dB. in either commercial (0 to +70°C), industrial (–40 Housed in a small 24-pin DDIP or SMT (gull- to +100°C), or HI-REL (–55 to +125°C) operating wing) package, the functionally complete ADS-927 temperature ranges. Applications include radar, contains a fast-settling sample-hold amplifi er, a sonar, spectrum analysis, and graphic/medical subranging (two-pass) A/D converter, a precise imaging. voltage reference, timing/control logic, and error- correction circuitry. Digital input and output levels are TTL. INPUT/OUTPUT CONNECTIONS FEATURES PIN FUNCTION PIN FUNCTION „ 14-bit resolution 1 BIT 14 (LSB) 24 –12V/–15V SUPPLY 2 BIT 13 23 ANALOG GROUND „ 1MHz sampling rate 3 BIT 12 22 +12V/+15V SUPPLY „ Functionally complete 4 BIT 11 21 +10V REFERENCE OUT „ No missing codes 5 BIT 10 20 ANALOG INPUT 6 BIT 9 19 ANALOG GROUND „ Small 24-pin DDIP or SMT package 7 BIT 8 18 BIT 1 (MSB) „ Low power, 1.9 Watts maximum 8 BIT 7 17 BIT 2 „ Operates from ±15V or ±12V supplies 9 BIT 6 16 START CONVERT +5V supply 10 BIT 5 15 EOC 11 BIT 4 14 DIGITAL GROUND „ Bipolar ±5V input range* 12 BIT 3 13 +5V SUPPLY *For unipolar 0 to +10V input range, see ADS-917 data sheet. BLOCK DIAGRAM DAC 18 BIT 1 (MSB) 17 BIT 2 +10V REF. OUT 21 REF 12 BIT 3 11 BIT 4 S2 10 BIT 5 FLASH 9 BIT 6 ADC 8 BIT 7 S/H S1 7 BIT 8 BUFFER 6 BIT 9 ANALOG INPUT 20 – 5 BIT 10 + 4 BIT 11 3 BIT 12 2 BIT 13 1 BIT 14 (LSB) START CONVERT 16 TIMING AND CONTROL LOGIC EOC 15 13 14 22 19, 23 24 +5V SUPPLY DIGITAL GROUND +12V/+15V SUPPLY ANALOG GROUND –12V/–15V SUPPLY Figure 1. ADS-927 Functional Block Diagram 02 Oct 2015 MDA_ADS-927.B04 Page 1 of 9 REGISTER REGISTER DIGITAL CORRECTION LOGIC ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters ABSOLUTE MAXIMUM RATINGS PHYSICAL/ENVIRONMENTAL PARAMETERS LIMITS UNITS PARAMETERS MIN. TYP. MAX. UNITS Operating Temp. Range, Case +12V/+15V Supply (Pin 22) 0 to +16 Volts –12V/–15V Supply (Pin 24) 0 to –16 Volts ADS-927MC, GC 0 — +70 °C +5V Supply (Pin 13) 0 to +6 Volts ADS-927ME, GE –40 — +100 °C ADS-927MM, GM –55 — +125 °C Digital Input (Pin 16) –0.3 to +VDD +0.3 Volts Thermal Impedance Analog Input (Pin 20) ±15 Volts Lead Temperature (10 seconds) +300 °C θjc — 6 — °C/Watt θca — 24 — °C/Watt Storage Temperature Range –65 — +150 °C Package Type 24-pin, metal-sealed, ceramic DDIP or SMT Weight 0.42 ounces (12 grams) FUNCTIONAL SPECIFICATIONS (TA = +25°C, ±VCC = ±15V (or ±12V), +VDD = +5V, 1MHz sampling rate, and a minimum 1 minute warmup ➀ unless otherwise specifi ed.) +25°C 0 TO +70°C –55 TO +125°C ANALOG INPUT MIN. TYP. MAX. MIN. TYP. MAX. MIN. TYP. MAX. UNITS Input Voltage Range ➁ —±5——±5——±5—Volts Input Resistance —1— —1— —1— kΩ Input Capacitance — 7 15 — 7 15 — 7 15 pF DIGITAL INPUT Logic Levels Logic "1" +2.0 — — +2.0 — — +2.0 — — Volts Logic "0" — — +0.8 — — +0.8 — — +0.8 Volts Logic Loading "1" — — +20 — — +20 — — +20 μA Logic Loading "0" — — –20 — — –20 — — –20 μA Start Convert Positive Pulse Width ➂ 175200225175200225175200225ns STATIC PERFORMANCE Resolution — 14 — — 14 — — 14 — Bits Integral Nonlinearity (fin = 10kHz) — ±0.5 — — ±0.75 — — ±1.5 — LSB Differential Nonlinearity (fin = 10kHz) — ±0.5 +0.95 — ±0.5 ±0.95 — ±0.75 +0.99 LSB Full Scale Absolute Accuracy— ±0.08±0.15—±0.15±0.25—±0.3±0.5%FSR Bipolar Zero Error (Tech Note 2) — ±0.05 ±0.1 — ±0.1 ±0.25 — ±0.15 ±0.3 %FSR Bipolar Offset Error (Tech Note 2) —±0.05±0.1—±0.1±0.25—±0.25±0.5%FSR Gain Error (Tech Note 2)—±0.1 ±0.15—±0.15±0.25—±0.25±0.5%FSR No Missing Codes (fin = 10kHz) 14 — — 14 — — 14 — — Bits DYNAMIC PERFORMANCE Peak Harmonics (–0.5dB) dc to 100kHz — –91–83—–90——–88—dB 100kHz to 500kHz — –82–78—–82–78—–80–77dB Total Harmonic Distortion (–0.5dB) dc to 100kHz — –90–81—–89——–87—dB 100kHz to 500kHz — –80–76—–80–76—–79–74dB Signal-to-Noise Ratio (w/o distortion, –0.5dB) dc to 100kHz 7779—7478—7377—dB 100kHz to 500kHz 7578—7478—7376—dB Signal-to-Noise Ratio (& distortion, –0.5dB) ➃ dc to 100kHz 7678—7377—7176—dB 100kHz to 500kHz 7376—7376—7175—dB Two-tone Intermodulation Distortion (fin = 100kHz, 240kHz, fs = 1MHz –0.5dB) — –87——–86——–85—dB Noise —350——350——350—μVrms Input Bandwidth (–3dB) Small Signal (–20dB input) —7——7——7—MHz Large Signal (–0.5dB input) —5——5——5—MHz Feedthrough Rejection (fin = 500kHz) —84— —84— —84— dB Slew Rate — ±60 — — ±60 — — ±60 — V/μs Aperture Delay Time — ±20 — — ±20 — — ±20 — ns Aperture Uncertainty —5— —5— —5— ps rms S/H Acquisition Time (to ±0.003%FSR, 10V step) 335390445335390445335390445ns Overvoltage Recovery Time ➄ — 4001000—4001000—4001000ns A/D Conversion Rate 1— —1— —1— — MHz DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 2 of 9 ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters +25°C 0 TO +70°C –55 TO +125°C ANALOG OUTPUT MIN. TYP. MAX. MIN. TYP. MAX. MIN. TYP. MAX. UNITS Internal Reference Voltage +9.95+10.0+10.05+9.95+10.0+10.05+9.95+10.0+10.05Volts Drift —±5——±5——±5—ppm/°C External Current ——1.5——1.5——1.5mA DIGITAL OUTPUTS Logic Levels Logic "1" +2.4 — — +2.4 — — +2.4 — — Volts Logic "0" — — +0.4 — — +0.4 — — +0.4 Volts Logic Loading "1" — — –4 — — –4 — — –4 mA Logic Loading "0" — — +4 — — +4 — — +4 mA Delay, Falling Edge of EOC to Output Data Valid — — 35 — — 35 — — 35 ns Output Coding Offset Binary POWER REQUIREMENTS , ±15V Power Supply Ranges +15V Supply +14.5 +15.0 +15.5 +14.5 +15.0 +15.5 +14.5 +15.0 +15.5 Volts –15V Supply –14.5 –15.0 –15.5 –14.5 –15.0 –15.5 –14.5 –15.0 –15.5 Volts +5V Supply +4.75 +5.0 +5.25 +4.75 +5.0 +5.25 +4.75 +5.0 +5.25 Volts Power Supply Currents +15V Supply— +43+70—+43+70—+43+70mA –15V Supply— –25–45—–25–45—–25–45mA +5V Supply— +71+80—+71+80—+71+80mA Power Dissipation — 1.61.95—1.61.95—1.61.95Watts Power Supply Rejection ——±0.02——±0.02——±0.02%FSR/%V POWER REQUIREMENTS, ±12V Power Supply Ranges +12V Supply +11.5+12.0+12.5+11.5+12.0+12.5+11.5+12.0+12.5Volts –12V Supply –11.5–12.0–12.5–11.5–12.0–12.5–11.5–12.0–12.5Volts +5V Supply +4.75 +5.0 +5.25 +4.75 +5.0 +5.25 +4.75 +5.0 +5.25 Volts Power Supply Currents +12V Supply— +42+70—+42+70—+42+70mA –12V Supply— –25–45—–25–45—–25–45mA +5V Supply— +71+80—+71+80—+71+80mA Power Dissipation— 1.41.65—1.41.65—1.41.65Watts Power Supply Rejection — — ±0.02 — — ±0.02 — — ±0.02 %FSR/%V Power Supply Rejection — — ±0.02 — — ±0.02 — — ±0.02 %FSR/%V Footnotes: ➃ Effective bits is equal to: ➀ All power supplies must be on before applying a start convert pulse. All supplies Full Scale Amplitude (SNR + Distortion) – 1.76 + 20 log and the clock (START CONVERT) must be present during warmup periods. Actual Input Amplitude The device must be continuously converting during this time. There is a slight 6.02 degradation in performance when using ±12V supplies. ➁ See Ordering Information for 0 to +10V input range. Contact DATEL for availability ➄ This is the time required before the A/D output data is valid after the analog input of other input voltage ranges. is back within the specifi ed range. ➂ A 1MHz clock with a 200ns wide start convert pulse is used for all production testing. For applications requiring less than a 1MHz sampling rate, wider start convert pulses can be used. See Timing Diagram for more details. TECHNICAL NOTES 1. Obtaining fully specifi ed performance from the ADS-927 requires care- can be reduced to zero using the input circuit of Figure 2. When using this ful attention to pc-card layout and power supply decoupling. The device's circuit, or any similar offset and gain-calibration hardware, make adjust- analog and digital ground systems are connected to each other internally. ments following warmup. To avoid interaction, always adjust offset before For optimal performance, tie all ground pins (14, 19 and 23) directly to a gain. large analog ground plane beneath the package. 3. When operating the ADS-927 from ±12V supplies, do not drive external Bypass all power supplies and the REFERENCE OUTPUT (pin 21) to ground circuitry with the REFERENCE OUTPUT. The reference's accuracy and drift with 4.7μF tantalum capacitors in parallel with 0.1μF ceramic capacitors. specifi cations may not be met, and loading the circuit may cause accuracy Locate the bypass capacitors as close to the unit as possible. If the user- errors within the converter. installed offset and gain adjusting circuit shown in Figure 2 is used, also 4. Applying a start convert pulse while a conversion is in progress (EOC = locate it as close to the ADS-927 as possible. logic "1") initiates a new and inaccurate conversion cycle. Data from the 2. The ADS-927 achieves its specifi ed accuracies without the need for exter- interrupted and subsequent conversions will be invalid. nal calibration. If required, the device's small initial offset and gain errors DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 3 of 9 ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters Gain adjusting is accomplished when all bits are 1's and the LSB just CALIBRATION PROCEDURE (Refer to Figures 2 and 3) changes from a 1 to a 0. This transition ideally occurs when the analog Any offset and/or gain calibration procedures should not be implemented input is at +full scale minus 1½ LSB's (+4.999085V). until devices are fully warmed up. To avoid interaction, offset must be Zero/Offset Adjust Procedure adjusted before gain. The ranges of adjustment for the circuit of Figure 2 are guaranteed to compensate for the ADS-927's initial accuracy errors 1. Apply a train of pulses to the START CONVERT input (pin 16) so the con- and may not be able to compensate for additional system errors. verter is continuously converting. If using LED's on the outputs, a 200kHz conversion rate will reduce fl icker. All fi xed resistors in Figure 2 should be metal-fi lm types, and multiturn potentiometers should have TCR’s of 100ppm/°C or less to minimize drift 2. Apply +305μV to the ANALOG INPUT (pin 20). with temperature. 3. Adjust the offset potentiometer until the output bits are a 1 and all 0's and A/D converters are calibrated by positioning their digital outputs exactly the LSB fl ickers between 0 and 1. on the transition point between two adjacent digital output codes. This can Gain Adjust Procedure be accomplished by connecting LED's to the digital outputs and adjusting until certain LED's "fl icker" equally between on and off. Other approaches 1. 1. Apply +4.999085V to the ANALOG INPUT (pin 20). employ digital comparators or microcontrollers to detect when the outputs change from one code to the next. 2. Adjust the gain potentiometer until the output bits are all 1's and the LSB fl ickers between 1 and 0. For the ADS-927, offset adjusting is normally accomplished at the point where the MSB is a 1 and all other output bits are 0's and the LSB just changes from a 0 to a 1. This digital output transition ideally occurs when Table 1. Zero and Gain Adjust the applied analog input is +½LSB (+305μV). INPUT VOLTAGE ZERO ADJUST GAIN ADJUST +15V RANGE +½ LSB +FS –1½ LSB 20kΩ 1.2MΩ 2kΩ ZERO/ ±5V +305μV +4.999085V OFFSET ADJUST Table 2. Output Coding GAIN ADJUST –15V +15V OUTPUT CODING INPUT RANGE BIPOLAR SCALE 1.98kΩ SIGNAL ±5V MSB LSB INPUT To Pin 20 50Ω of ADS-927 11 1111 1111 1111 +4.99939 +FS –1 LSB 11 1000 0000 0000 +3.75000 +3/4 FS –15V 11 0000 0000 0000 +2.50000 +1/2FS Figure 2. ADS-927 Calibration Circuit 10 0000 0000 0000 0.00000 0 01 0000 0000 0000 –2.50000 –1/2FS 00 1000 0000 0000 –3.75000 –3/4FS 00 0000 0000 0001 –4.99939 –FS +1 LSB 00 0000 0000 0000 –5.00000 –FS Coding is offset binary; 1LSB = 610μV. 18 BIT 1 (MSB) +5V 13 17 BIT 2 + 12 BIT 3 4.7μF 0.1μF DIGITAL 11 BIT 4 14 GROUND 10 BIT 5 9 BIT 6 ADS-927 8 BIT 7 –12V/–15V 24 7 BIT 8 4.7μF 0.1μF + 6 BIT 9 ANALOG 19, 23 GROUND 5 BIT 10 4.7μF 0.1μF 4 BIT 11 + +12V/+15V 22 3 BIT 12 2 BIT 13 ANALOG 0 to +10V 20 INPUT 1 BIT 14 (LSB) 15 EOC 21 +10V REF. OUT + START 0.1μF 4.7μF 16 CONVERT Figure 3. Typical ADS-927 Connection Diagram DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 4 of 9 ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters THERMAL REQUIREMENTS devices do not overheat. The ground and power planes beneath the package, All DATEL sampling A/D converters are fully characterized and speci- as well as all pcb signal runs to and from the device, should be as heavy as fi ed over operating temperature (case) ranges of 0 to +70°C and –55 possible to help conduct heat away from the package. to +125°C. All room-temperature (TA = +25°C) production testing is performed without the use of heat sinks or forced-air cooling. Thermal Electrically-insulating, thermally-conductive "pads" may be installed impedance fi gures for each device are listed in their respective specifi ca- underneath the package. Devices should be soldered to boards rather than tion tables. "socketed," and of course, minimal air fl ow over the surface can greatly help reduce the package temperature. These devices do not normally require heat sinks; however, standard precautionary design and layout procedures should be used to ensure NN + 1 START CONVERT 200ns ±25ns 10ns typ. Hold Acquisition Time 610ns typ. INTERNAL S/H 390ns ±55ns 10ns typ. 70ns ±10ns Conversion Time EOC 480ns ±20ns 35ns max. 150ns max. OUTPUT Data (N – 1) Valid Data N Valid (850ns min.) DATA Invalid Data Notes: 1. fs = 1MHz. 2. The ADS-927 is a pulse-triggered device. Its internal operations are triggered by both the rising and falling edges of the start convert pulse. When sampling at 1MHz, the start pulse must be between 175 and 225nsec wide. For lower sampling rates, wider start pulses may be used, however, a minimum pulse width low of 50nsec must be maintained. Figure 4. ADS-927 Timing Diagram DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 5 of 9 ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 6 of 9 Figure 5. ADS-927 Evaluation Board Schematic ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 –130 –140 –150 0 50 100 150 200 250 300 350 400 450 500 Frequency (kHz) (fs = 1MHz, fin = 480kHz, Vin = –0.5dB, 16,384-point FFT) Figure 6. ADS-927 FFT Analysis +0.71 0 –0.49 0 16,384 Digital Output Code 0 16,384 Digital Output Code Figure 7. ADS-927 Histogram and Differential Nonlinearity DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 7 of 9 Amplitude Relative to Full Scale (dB) Number of Occurrences DNL (LSB's) ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters MECHANICAL DIMENSIONS - INCHES (mm) 1.31 MAX. (33.27) Dimension Tolerances (unless otherwise indicated): 24-Pin DDIP 2 place decimal (.XX) ±0.010 (±0.254) Versions 3 place decimal (.XXX) ±0.005 (±0.127) 24 13 Lead Material: Kovar alloy 0.80 MAX. ADS-927MC (20.32) Lead Finish: 50 microinches (minimum) gold plating over 100 microinches (nominal) nickel plating ADS-927MC-C 112 ADS-927ME ADS-927ME-C 0.100 TYP. ADS-927MM (2.540) 1.100 ADS-927MM-C (27.940) ADS-927/883 0.235 MAX. (5.969) ADS-927-C/883 PIN 1 INDEX 0.200 MAX. 5962-9475701HXC (5.080) 5962-9475701HXA +0.002 0.010 –0.001 (0.254) 0.190 MAX. 0.100 0.100 (4.826) (2.540) (2.540) 0.600 ±0.010 SEATING (15.240) PLANE 0.040 0.018 ±0.002 0.025 (1.016) (0.457) (0.635) 1.31 MAX. (33.02) 24-Pin Dimension Tolerances (unless otherwise indicated): 13 24 Surface Mount 2 place decimal (.XX) ±0.010 (±0.254) 3 place decimal (.XXX) ±0.005 (±0.127) Versions Lead Material: Kovar alloy 0.80 MAX. Lead Finish: 50 microinches (minimum) gold plating (20.32) ADS-927GC over 100 microinches (nominal) nickel plating ADS-927GC-C 1 12 ADS-927GE ADS-927GE-C ADS-927GM ADS-927GM-C 0.020 TYP. 0.060 TYP. 0.015 ADS-927G/883 (0.508) (1.524) 0.190 MAX. (0.381) (4.826) MAX. radius ADS-927G-C/883 0.130 TYP. PIN 1 for any pin (3.302) INDEX 0.100 (2.540) 0.020 0.010 TYP. (0.508) (0.254) 0.100 TYP. 0.040 (2.540) (1.016) DATEL, Inc. 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA • Tel: (508) 339-3000 • www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 8 of 9 ADS-927 14-Bit, 1MHz, Low-Power Sampling A/D Converters ORDERING INFORMATION OPERATING MODEL NUMBER PACKAGE ROHS ACCESSORIES TEMP. RANGE ADS-927MC 0 to +70°C DDIP No ADS-B926/927 Evaluation Board (without ADS-927) ADS-927MC-C 0 to +70°C DDIP Yes HS-24 Heat Sinks for all ADS-917/927 DDIP models ADS-927ME –40 to +100°C DDIP No ADS-927ME-C –40 to +100°C DDIP Yes Receptacles for PC board mounting can be ordered through AMP Inc. ADS-927MM –55 to +125°C DDIP No Part #3-331272-8 (Component Lead Socket), 24 required. ADS-927MM-C –55 to +125°C DDIP Yes For MIL-STD-883 product specifi cations, contact DATEL. ADS-927/883 –55 to +125°C DDIP No For unipolar analog input 0 to +10V, see ADS-917 data sheet. ADS-927-C/883 –55 to +125°C DDIP Yes ADS-927GC 0 to +70°C SMT No ADS-927GC-C 0 to +70°C SMT Yes ADS-927GE –40 to +100°C SMT No ADS-927GE-C –40 to +100°C SMT Yes ADS-927GM –55 to +125°C SMT No ADS-927GM-C –55 to +125°C SMT Yes ADS-927G/883 –55 to +125°C SMT No ADS-927G-C/883 –55 to +125°C SMT Yes 5962-9475701HXC –55 to +125°C DDIP No 5962-9475701HXA –55 to +125°C DDIP No DATEL is a registered trademark of DATEL, Inc. DATEL, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply the granting of 11 Cabot Boulevard, MansŢ eld, MA 02048-1151 USA licenses to make, use, or sell equipment constructed in accordance therewith. Specifi cations are subject to change without notice. ITAR and ISO 9001/14001 REGISTERED © 2015 DATEL, Inc. www.datel.com • e-mail: help@datel.com 02 Oct 2015 MDA_ADS-927.B04 Page 9 of 9