® ® ADS-117 12-Bit, 2MHz, Low-Power Sampling A/D Converters FEATURES • • • • • • • • 12-bit resolution No missing codes 2MHz minimum throughput Functionally complete Small 24-pin DDIP Low-power, 1.6 Watts Three-state output buffers Samples to Nyquist frequencies INPUT/OUTPUT CONNECTIONS GENERAL DESCRIPTION DATEL's ADS-117 is a functionally complete, 12-bit, 2MHz, sampling A/D converter. Its standard, 24-pin, double-width DIP contains a fast-settling sample-hold amplifier, a 12-bit subranging (two-step) A/D converter, a precision reference, three-state output register and all the timing and control logic necessary to operate from a single start convert pulse. Digital input and output levels are TTL. PIN FUNCTION PIN FUNCTION 1 2 3 4 5 6 7 8 9 10 11 12 BIT 12 (LSB) BIT 11 BIT 10 BIT 9 BIT 8 BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 (MSB) 24 23 22 21 20 19 18 17 16 15 14 13 –15V SUPPLY ANALOG GROUND +15V SUPPLY +10V REFERENCE BIPOLAR ANALOG INPUT COMP BIN ENABLE (1-12) START CONVERT EOC DIGITAL GROUND +5V SUPPLY Total harmonic distortion (THD) and signal-to-noise ratio (including distortion) typically run –78dB and 70dB, respectively, with full scale inputs up to 100kHz. The ADS117 requires ±15V and +5V power supplies and typically consumes 1.6 Watts. Models are available for use in either commercial (0 to +70°C) or military (–55 to +125°C) operating temperature ranges. 17 ENABLE (1-12) DAC 12 BIT 1 (MSB) REF S1 BUFFER ANALOG INPUT 19 REGISTER BIPOLAR 20 – + 3-STATE OUTPUT REGISTER FLASH ADC S/H DIGITAL CORRECTION LOGIC S2 11 BIT 2 REGISTER +10V REF. 21 10 BIT 3 9 BIT 4 8 BIT 5 7 BIT 6 6 BIT 7 5 BIT 8 4 BIT 9 3 BIT 10 2 BIT 11 1 BIT 12 (LSB) COMP BIN 18 START CONVERT 16 TIMING AND CONTROL LOGIC EOC 15 13 14 22 23 24 +5V SUPPLY DIGITAL GROUND +15V SUPPLY ANALOG GROUND –15V SUPPLY Figure 1. ADS-117 Functional Block Diagram DATEL, Inc., 11 Cabot Boulevard, Mansfield, MA 02048-1151 (U.S.A.) • Tel: (508) 339-3000 Fax: (508) 339-6356 • For immediate assistance: (800) 233-2765 ® ® ADS-117 ABSOLUTE MAXIMUM RATINGS PARAMETERS +15V Supply (Pin 22) –15V Supply (Pin 24) +5V Supply (Pin 13) Digital Inputs (Pin 16, 17, 18) Analog Input (Pin 19) Lead Temp. (10 seconds) DYNAMIC PERF. (cont) LIMITS UNITS 0 to +16 0 to –16 0 to +6.0 –0.3 to +VDD +0.3 –9 to +15 +300 Volts Volts Volts Volts Volts °C SNR (wo/distortion, –0.5dB) dc to 100kHz 0°C to +70°C –55°C to +125°C 100kHz to 500kHz 0°C to +70°C –55°C to +125°C 500kHz to 1MHz 0°C to +70°C –55°C to +125°C SNR (and distort., –0.5dB) ➂ dc to 100kHz 0°C to +70°C –55°C to +125°C 100kHz to 500kHz 0°C to +70°C –55°C to +125°C 500kHz to 1MHz 0°C to +70°C –55°C to +125°C Two-tone Intermodulation Distortion (fin = 970kHz, 990kHz, fs = 2Mhz, –0.5dB) Slew Rate Effect. Aperture Delay Time Overvoltage Recovery Time; 20% S/H Acq. Time, (to ±0.01%) 0 to +70°C –55°C to +125°C Conversion Rate FUNCTIONAL SPECIFICATIONS (TA = +25°C, ±VCC = +15V, +VDD =+5V, 2MHz sampling rate, and a minimum 3 minute warmup unless otherwise specified.) ANALOG INPUTS MIN. TYP. MAX. UNITS Input Voltage Range ➀ Bipolar Unipolar Input Impedence Input Capacitance — — 4.5 — ±5 0 to +10 5 6 — — — 15 Volts Volts kΩ pF +2.0 — — — — — — — — +0.8 +5 –600 Volts Volts µA µA DIGITAL INPUTS Logic Levels Logic "1" Logic "0" Logic Loading "1" Logic Loading "0" PERFORMANCE Resolution No Missing Codes (12 Bits; fin = 1MHz) Integral Non-Linearity 0°C to +70°C –55°C to +125°C Differential Non-Linearity 0°C to +70°C –55°C to +125°C Full Scale Absolute Accuracy (see Tech Note 1) 0°C to +70°C –55°C to +125°C Unipolar/Bipolar Zero Error 0°C to +70°C (see Tech Note 1) –55°C to +125°C Bipolar Offset Error 0°C to +70°C (see Tech Note 1) –55°C to +125°C Gain Error (see Tech Note 1) 0°C to +70°C –55°C to +125°C Internal Reference Voltage 0°C to +70°C –55°C to +125°C External Current 12 Bits 0 to +70°C TYP. MAX. UNITS — — 72 72 — — dB dB 65 65 70 70 — — dB dB — — 70 70 — — dB dB — — 70 69 — — dB dB 64 62 70 69 — — dB dB — — 69 69 — — dB dB — — — –68 ±210 — — — 16 dB V/µs ns — — 500 ns — — 2 155 160 — 165 170 — ns ns MHz OUTPUTS — — ±1/2 ±1 ±3 ±4 LSB LSB — — ±1/2 ±1 ±0.95 +1.5 LSB LSB — — ±0.13 ±0.25 ±0.44 ±0.73 %FSR %FSR — — ±0.07 ±0.22 ±0.38 ±0.73 %FSR %FSR — — ±0.1 ±0.53 ±0.38 ±0.73 %FSR %FSR — — ±0.1 ±0.53 ±0.38 ±0.73 % % +9.97 +9.95 — +10.0 — — +10.03 +10.05 1.5 Volts Volts mA Output Coding Pin 18 High Pin 18 Low Logic Level Logic "1" Logic "0" Logic Loading "1" Logic Loading "0" Staight binary/Offset binary Complementary binary Complementary offset binary +2.4 — — — — — — — — +0.4 –160 +6.4 Volts Volts µA mA +14.25 –14.25 +4.75 +15.0 –15.0 +5.0 +15.75 –15.75 +5.25 Volts Volts Volts — — — — — +48 –35 +75 1.6 — +58 –45 +85 1.9 ±0.07 mA mA mA Watts %FSR%V 0 –55 –65 — — — +70 +125 +150 °C °C °C POWER REQUIREMENTS Power Supply Ranges ➃ +15V Supply –15V Supply +5V Supply Power Supply Current +15V Supply –15V Supply +5V Supply Power Dissipation Power Supply Rejection PHYSICAL/ENVIRONMENTAL DYNAMIC PERFORMANCE Spurious Free Dynamic Range (–0.5dB) ➁ dc to 100kHz 100kHz to 500kHz 500kHz to 1MHz Total Harm. Distort. (–0.5dB) dc to 100kHz 100kHz to 500kHz 500kHz to 1MHz Input Bandwith (–3dB) Small Signal (–20dB input) Large Signal (–0.5dB input) Feedthrough (1MHz) MIN. — — — –81 –75 –70 — –70 — dB dB dB — — — –78 –73 –71 — –68 — dB dB dB 8 7 –72 10 9 –74 — — — MHz MHz dB Operating Temp. Range, Case ADS-117MC ADS-117MM, 883 Storage Temperature Range Thermal Impedance θjc θca Package Type Weight — 3 — °C/W — 23 — °C/W 24-pin, metal-sealed, ceramic DDIP 0.42 ounces (12 grams) ➂ Effective bits is equal to: (SNR + Distortion) – 1.76 + ➀ See Table 1 also 20 log 6.02 ➃ For ±12V, +5V operation, contact DATEL ➁ Same specifications for in-band harmonics. 2 Full Scale Amplitude Actual Input Amplitude ® ® ADS-117 TECHNICAL NOTES output coding, tie pin 18 to ground. The pin 18 signal is compatible with CMOS/TTL logic levels for those users desiring dynamic control of this function. Do not change COMP BIN status while EOC is high. 1. Applications which are unaffected by endpoint errors or remove them through software will use the typical connections shown in Figure 3. Remove system errors or adjust the small initial errors of the ADS-117 to zero using the optional external circuitry shown in Figure 4. The external adjustment circuit has no effect on the throughput rate. 5. To enable the three-state outputs, connect ENABLE (pin 17) to a logic "0" (low). To disable, connect pin 17 to a logic "1" (high). 2. Always connect the analog and digital grounds to a ground plane beneath the converter for best performance. The analog and digital grounds are not connected to each other internally. 6. To meet the guaranteed conversion rate, a maximum start convert pulse is specified. A wider start convert pulse will result in slower conversion rates. An initial start convert pulse is required before performing an actual conversion after power-up to assure the sample-hold is in the acquisition mode. 3. Bypass the analog and digital supplies and the +10V reference (pin 21) to ground with 4.7µF, 25V tantalum electrolytic capacitors in parallel with 0.1µF ceramic capacitors. Bypass the +10V reference (pin 21) to ANALOG GROUND (pin 23). Figure 2 shows the relationship between the various input signals. The timing shown applies over the operating temperature range and over the operating power supply range. 4. Obtain straight binary/offset binary output coding by tying COMP BIN (pin 18) to +5V or leaving it open. The device has an internal pull-up resistor on this pin. To obtain complementary binary or complementary offset binary 7. Re-initiating the START CONVERT (pin 16) while EOC is a logic "1" (high) will result in a new conversion sequence. N N+1 START CONVERT 50ns typ., 30ns min., 60ns max. 10ns min. 25ns max. Acquisition Time INTERNAL S/H 165ns typ. 170ns max. Hold 10ns min. 17ns max. EOC 60ns max. Conversion Time 325ns typ. 35ns max. OUTPUT DATA DATA N-1 VALID 350ns min. DATA N VALID INVALID DATA 150ns max. Note: Scale is approximately 25ns per division. Figure 2. ADS-117 Timing Diagram 3 INVALID DATA ® ® ADS-117 CALIBRATION PROCEDURE R2 ➀ 1. Connect the converter per Figure 3, Figure 4, and Table 1 for the appropriate input range. Apply a pulse of 150 nanoseconds to the START CONVERT input (pin 16) at a rate of 250kHz. This rate is chosen to reduce flicker if LED’s are used on the outputs for calibration purposes. SIGNAL INPUT 50Ω GAIN ADJUST Apply a precision voltage reference source between the amplifier’s analog input and ground. Adjust the output of the reference source per Table 2. For unipolar, adjust the zero trimming potentiometer so that the output code flickers equally between 0000 0000 0000 and 0000 0000 0001 with the pin 18 tied high (straight binary) or between 1111 1111 1111 and 1111 1111 1110 with the pin 18 tied low (complementary binary). 10kΩ ZERO/ OFFSET ADJUST ➀ For values of R1 and R2 refer to Table 1. Figure 4. Optional Calibration Circuit Table 1. Input Connections (using external calibration) 3. Full-Scale Adjustment Set the output of the voltage reference used in step 2 to the value shown in Table 1. Adjust the gain trimming potentiometer so that the output code flickers equally between 1111 1111 1110 and 1111 1111 1111 for pin 18 tied high or between 0000 0000 0001 and 0000 0000 0000 for pin 18 tied low. INPUT RANGE R1 R2 UNIT 0 +10V, ±5 0 to 5V, ±2.5V 0 to +2.5V, ±1.25V 2 2 2 2 6 14 kΩ kΩ kΩ Table 2. Zero and Gain Adjustments 4. To confirm proper operation of the device, vary the precision reference voltage source to obtain the output coding listed in Table 3. Input Range Zero Adjust +1/2 LSB Gain Adjust +FS – 1 1/2 LSB 0 to +10V ±5V +1.22mV +1.22mV +9.9963V +4.9963V UNIPOLAR OPERATION 20 BIPOLAR INPUT 12 BIT 1 (MSB) 11 BIT 2 21 +10V REF. 10 BIT 3 9 BIT 4 + 8 BIT 5 7 BIT 6 4.7µF 6 5 4 3 24 ADS-117 4.7µF + 0.1µF + 0.1µF 23 2 1 15 17 4.7µF +15V 22 + 4.7µF BIT 7 BIT 8 BIT 9 BIT 10 BIT 11 BIT 12 (LSB) EOC ENABLE (1-12) 16 START CONVERT 13 +5V –15V 5kΩ For bipolar operation, adjust the potentiometer such that the code flickers equally between 1000 0000 0000 and 1000 0000 0001 with pin 18 tied high (offset binary) or between 0111 1111 1111 and 0111 1111 1110 with pin 18 tied low (complementary offset binary). –15V To Pin19 of ADS-117 5kΩ 2. Zero Adjustments 0.1µF +15V ➀ R1 19 ANALOG INPUT 0.1µF COMP BIN 18 14 +5V NOTE: For unipolar operation, ground pin 20. For bipolar operation, connect pin 20 to pin 21. Always bypass pin 21 as shown for both unipolar and bipolar operation. Figure 3. ADS-117 Connection Diagram 4 ® ® ADS-117 Table 3. Output Coding STRAIGHT BIN. UNIPOLAR SCALE INPUT RANGE 0 to +10V +FS – 1 LSB +7/8 FS +3/4 FS +1/2 FS +1/4 FS +1/8 FS +1 LSB 0 +9.9976 +8.7500 +7.5000 +5.0000 +2.5000 +1.2500 +0.0024 0.0000 COMP. BINARY OUTPUT CODING MSB LSB MSB 1111 1110 1100 1000 0100 0010 0000 0000 1111 0000 0000 0000 0000 0000 0000 0000 1111 0000 0000 0000 0000 0000 0001 0000 0000 0001 0011 0111 1011 1101 1111 1111 OFF. BINARY LSB 0000 1111 1111 1111 1111 1111 1111 1111 0000 1111 1111 1111 1111 1111 1110 1111 INPUT RANGE ±5V BIPOLAR SCALE +4.9976 +3.7500 +2.5000 0.0000 –2.5000 –3.7500 –4.9976 –5.0000 +FS –1 LSB +3/4FS +1/2FS 0 –1/2FS –3/4FS –FS+1LSB –FS COMP. OFF. BIN. 0 Amplitude Relative to Full Scale (dB) –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 –130 –140 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Frequency (MHz) (fs = 2MHz, fin = 980kHz, Vin = –0.5dB, 4,096-point FFT) Figure 5. FFT Analysis of ADS-117 5 0.9 1.0 ® ® ADS-117 MECHANICAL DIMENSIONS INCHES (mm) 1.31 MAX. (33.27) 24 Dimension Tolerances (unless otherwise indicated): 2 place decimal (.XX) ±0.010 (±0.254) 3 place decimal (.XXX) ±0.005 (±0.127) 13 0.80 MAX. (20.32) 1 Lead Material: Kovar alloy Lead Finish: 50 microinches (minimum) gold plating over 100 microinches (nominal) nickel plating 12 0.100 TYP. (2.540) 1.100 (27.940) 0.235 MAX. (5.969) PIN 1 INDEX 0.200 MAX. (5.080) 0.010 (0.254) 0.190 MAX. (4.826) 0.100 (2.540) 0.040 (1.016) 0.018 ±0.002 (0.457) SEATING PLANE 0.025 (0.635) +0.002 –0.001 0.600 ±0.010 (15.240) 0.100 (2.540) ORDERING INFORMATION MODEL NUMBER OPERATING TEMP. RANGE ADS-117MC ADS-117MM ADS-117/883 ACCESSORIES ADS-EVAL1 HS-24 0 to +70°C –55 to +125°C –55 to +125°C Evaluation Board (without ADS-117) Heat Sink for all ADS-117 models For MIL-STD-883 product specification or availability of surface-mount packaging, contact DATEL. Receptacles for PC mounting can be ordered through AMP Inc., Part # 3-331272-8 (Component Lead Socket), 24 required. ® ® ISO 9001 DATEL, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356 Internet: www.datel.com E-mail:[email protected] DS-0230F 07/04 DATEL (UK) LTD. Tadley, England Tel: (01256)-880444 DATEL S.A.R.L. Montigny Le Bretonneux, France Tel: 1-34-60-01-01 DATEL GmbH München, Germany Tel: 89-544334-0 DATEL KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-6354-2025 DATEL China, Shanghai, China Tel:011-86-51317199 DATEL 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 licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. 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