View ADS-112_124710.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

(R)
(R)
ADS-112
12-Bit, 1MHz, Low-Power Sampling A/D Converters
FEATURES
* * * * * * * * 12-bit resolution No missing codes 1MHz minimum sampling rate Functionally complete Small 24-pin DDIP Low-power, 1.3 Watts Three-state output buffers Samples to Nyquist frequencies
GENERAL DESCRIPTION
DATEL's ADS-112 is a 12-bit, functionally complete, sampling A/D converter that is packaged in a space-saving 24-pin DDIP. Requiring 15V and +5V supplies, a minimum sampling rate of 1MHz is achieved while only dissipating 1.3 Watts. The ADS-112 digitizes signals up to Nyquist frequencies. Models are available for use in either commercial (0 to + 70C) or military (-55 to +125C) operating temperature ranges. Typical applications include spectrum, transient, vibration and waveform analysis. This device is also ideally suited for radar, sonar, video digitization, medical instrumentation and highspeed data acquisition systems.
PIN 1 2 3 4 5 6 7 8 9 10 11 12
INPUT/OUTPUT CONNECTIONS
FUNCTION 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) PIN 24 23 22 21 20 19 18 17 16 15 14 13 FUNCTION -15V SUPPLY ANALOG GROUND +15V SUPPLY +10V REFERENCE BIPOLAR ANALOG INPUT COMP BIN ENABLE (1-12) START CONVERT EOC DIGITAL GROUND +5V SUPPLY
17 ENABLE (1-12) DAC
12 BIT 1 (MSB) +10V REF. 21 S2 S/H S1 BIPOLAR 20 REGISTER BUFFER FLASH ADC REF DIGITAL CORRECTION LOGIC 3-STATE OUTPUT REGISTER 11 BIT 2 10 BIT 3 9 8 7 6 5 4 3 2 1 BIT 4 BIT 5 BIT 6 BIT 7 BIT 8 BIT 9 BIT 10 BIT 11 BIT 12 (LSB)
ANALOG INPUT 19
- +
COMP BIN 18 START CONVERT 16 EOC 15 TIMING AND CONTROL LOGIC
13 +5V SUPPLY
14 DIGITAL GROUND
22 +15V SUPPLY
REGISTER 23 ANALOG GROUND
24 -15V SUPPLY
Figure 1. ADS-112 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
(R)
(R)
ADS-112
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) LIMITS 0 to +18 0 to -18 0 to +6 -0.3 to +VDD +0.3 -9 to +15 +300 UNITS Volts Volts Volts Volts Volts C DYNAMIC PERF. (cont) Signal-to-Noise Ratio (wo/distort., -0.5dB) dc to 100kHz 100kHz to 500kHz Signal-to-Noise Ratio (& distort., -0.5dB) dc to 100kHz 100kHz to 500kHz Two-tone Intermodulation Distortion (fin = 75kHz, 105kHz, fs = 1MHz, -0.7dB) Two-tone Intermodulation Distortion (fin = 480kHz, 490kHz, fs = 1MHz, -0.7dB) Input Bandwith (-3dB) Small Signal (-20dB input) Large Signal (-0.5dB input) Slew Rate Apperture Delay TIme Effect. Aperture Delay Time Apperture Uncertainity (Jitter) RMS Peak Overvoltage Recovery Time S/H Acquisition Time Conversion Rate (Changing Inputs) +25C 0C to +70C -55C to +125C DIGITAL OUTPUTS Output Coding Pin 18 High Pin 18 Low Logic Level Logic "1" Logic "0" Logic Loading "1" Logic Loading "0" POWER REQUIREMENTS Power Supply Ranges +15V Supply -15V Supply +5V Supply Power Supply Current +15V Supply -15V Supply +5V Supply Power Dissipation Power Supply Rejection PHYSICAL/ENVIRONMENTAL -- -- +9.98 -- -- 0.1 0.3 +10.0 5 -- 0.38 0.60 +10.02 30 1.5 % % Volts ppm/C mA Operating Temp. Range, Case ADS-112MC ADS-112MM, 883 Storage Temperature Range Package Type Weight See Table 3 also Effective bits is equal to:
(SNR + Distortion) - 1.76 + 20 log 6.02 Full Scale Amplitude Actual Input Amplitude
MIN.
TYP.
MAX.
UNITS
68 67 66 66 -- -- 8 6 -- -- -- -- -- -- 160 1 1 1
72 71 70 70 -88 -68 10 8 150 -- -- -- -- -- 250 -- -- --
-- -- -- -- -80 -65 -- -- -- 20 16 15 50 1000 280 -- -- --
dB dB dB dB dB dB MHz MHz V/s ns ns ps ps ns ns MHz MHz MHz
FUNCTIONAL SPECIFICATIONS
(TA = +25C, VCC = 15V, +VDD =+5V, 1MHz sampling rate, and a minimum 1 minute warmup unless otherwise specified.) ANALOG INPUTS Input Voltage Range Bipolar Unipolar Input Impedence Input Capacitance 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 +25C 0C to +70C -55C to +125C Differential Non-Linearity +25C 0C to +70C -55C to +125C Full Scale Absolute Accuracy +25C 0C to +70C -55C to +125C Unipolar Zero Error 0C to +70C -55C to +125C Bipolar Zero Error 0C to +70C -55C to +125C Bipolar Offset Error 0C to +70C -55C to +125C Gain Error 0C to +70C -55C to +125C Internal Reference Voltage, +25C Drift External Current DYNAMIC PERFORMANCE In-Band Harmonics (-0.5dB) dc to 100kHz 100kHz to 500kHz Total Harm. Distort. (-0.5dB) dc to 100kHz 100kHz to 500kHz See Tech Note 1 -- -- -- -- -81 -75 -78 -73 -75 -70 -75 -68 dB dB dB dB 12 Bits Over the operating temperature range -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 1/4 1/4 1/2 1/4 1/4 1/2 0.13 0.15 0.25 0.074 0.224 0.074 0.124 0.1 0.3 3/4 3/4 1.5 3/4 3/4 1 0.25 0.44 0.78 0.265 0.43 0.166 0.210 0.38 0.60 LSB LSB LSB LSB LSB LSB %FSR %FSR %FSR %FSR %FSR %FSR %FSR %FSR %FSR +2.0 -- -- -- -- -- -- -- -- +0.8 +10 -600 Volts Volts A A MIN. -- -- 4.5 -- TYP. 5 0 to +10 5 6 MAX. -- -- -- 15 UNITS Volts Volts k pF
Staight binary/Offset binary Complementary binary Complementary offset binary +2.4 -- -- -- -- -- -- -- -- +0.4 -160 +6.4 Volts Volts A mA
+14.25 -14.25 +4.75 -- -- -- -- --
+15.0 -15.0 +5.0 +24 -40 +80 1.3 --
+15.75 -15.75 +5.25 +35 -48 +95 1.7 0.07
Volts Volts Volts mA mA mA Watts %FSR%V
0 -- +70 C -55 -- +125 C -65 -- +150 C 24-pin, metal-sealed, ceramic DDIP 0.42 ounces (12 grams)
For 12V, +5V operation, contact DATEL
2
(R)
(R)
ADS-112
TECHNICAL NOTES
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-112 to zero using the optional external circuitry shown in Figure 4. The external adjustment circuit has no effect on the throughput rate. 2. For best performance, always connect the analog and digital ground pins to a ground plane beneath the converter. The analog and digital grounds are not connected to each other internally. 3. Bypass the analog and digital supplies and the +10V reference (pin 21) to ground with 4.7F, 25V tantalum electrolytic capacitors in parallel with 0.1F ceramic capacitors. Bypass the +10V reference (pin 21) to analog ground (pin 23). 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 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. 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). 6. Do not change the status of pin 18 when EOC is high. 7. Re-initiating the START CONVERT (pin 16) while EOC is a logic "1" (high) will result in a new conversion sequence.
TIMING
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. These times are guaranteed by design.
N START CONVERT 150ns, 25ns
N+1
10ns min. 20ns max. INTERNAL S/H Hold
Acquisition Time 250ns
20ns max. EOC Conversion Time 600ns max.
60ns max.
35ns max. OUTPUT DATA DATA N-1 VALID 800ns min. INVALID DATA 200ns max. DATA N VALID INVALID DATA
Note: Scale is approximately 50ns per division.
Figure 2. ADS-112 Timing Diagram
3
(R)
(R)
ADS-112
CALIBRATION PROCEDURE
1. Connect the converter per Figures 3 and 4 and Tables 1 and 3 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 the flicker if LED's are used on the outputs for calibration purposes. 2. Zero Adjustments 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 COMP BIN (pin 18) tied high (straight binary) or between 1111 1111 1111 and 1111 1111 1110 with pin 18 tied low (complementary binary). 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). 3. Full-Scale Adjustment Set the output of the voltage reference used in step 2 to the value shown in Table 2. 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. To confirm proper operation of the device, vary the precision reference voltage source to obtain the output coding listed in Table 4.
Table 1. Input Range Selection
R2
R1 SIGNAL INPUT
+15V
5k 50 GAIN ADJUST 5k 10k ZERO/ OFFSET ADJUST -15V
To Pin19 of ADS-112
For values of R1 and R2 refer to Table 3. Figure 4. Optional Calibration Circuit
Table 2. Zero and Gain Adjust
Input Range 0 to +10V 5V
Zero Adjust +1/2 LSB +1.22mV +1.22mV
Gain Adjust +FS - 1 1/2 LSB +9.9963V +4.9963V
Table 3. Input Range (using external calibration)
INPUT RANGE 0 to 10V, 5 0 to 5V, 2.5V 0 to +2.5V, 1.25V
R1 2 2 2
R2 2 6 14
UNIT k k k
INPUT RANGE 5v 0 to +10V
INPUT PIN Pin 19 Pin 19
TIE TOGETHER Pin 20 to Pin 21 Pin 20 to Ground
BIPOLAR OPERATION 20 21
UNIPOLAR OPERATION 20 21 +10V REF. + 0.1F 4.7F
-15V 4.7F 4.7F +15V +5V 4.7F + 0.1F + 0.1F
24
ADS-112
23
22 13
12 BIT 1 (MSB) 11 BIT 2 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) 15 EOC 17 ENABLE (1-12) 16 START CONVERT 19 ANALOG INPUT
+ 0.1F 14 COMP BIN 18 Note: Always bypass pin 21 to ground
+5V
Figure 3. Typical ADS-112 Connection Diagram
4
(R)
(R)
ADS-112
Table 4. Output Coding STRAIGHT BIN. UNIPOLAR SCALE INPUT RANGE 0 to +10V COMP. BINARY LSB INPUT RANGE 5V BIPOLAR SCALE
OUTPUT CODING MSB LSB MSB
+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
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
0000 1111 1111 1111 1111 1111 1111 1111
0000 1111 1111 1111 1111 1111 1110 1111
+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
OFF. BINARY
COMP. OFF. BIN.
0 -10 Amplitude Relative to Full Scale (dB) -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 0 50 100 150 200 250 300 350 400 450 500
Frequency (kHz) (fs = 1MHz, fin = 485kHz, Vin = -0.5dB, 4,096-point FFT)
Figure 5. FFT Analysis of ADS-112
5
(R)
(R)
ADS-112
MECHANICAL DIMENSIONS INCHES (mm)
1.31 MAX. (33.27) Dimension Tolerances (unless otherwise indicated): 2 place decimal (.XX) 0.010 (0.254) 3 place decimal (.XXX) 0.005 (0.127) 0.80 MAX. (20.32) 1 12 Lead Material: Kovar alloy Lead Finish: 50 microinches (minimum) gold plating over 100 microinches (nominal) nickel plating
24
13
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) 0.018 0.002 (0.457) 0.100 (2.540) 0.040 (1.016)
+0.002 -0.001
SEATING PLANE 0.025 (0.635)
0.600 0.010 (15.240)
0.100 (2.540)
ORDERING INFORMATION
MODEL NUMBER ADS-112MC ADS-112MM ADS-112/883 OPERATING TEMP. RANGE 0 to +70C -55 to +125C -55 to +125C ACCESSORIES ADS-EVAL4 HS-32 Evaluation Board (without ADS-112) Heat Sink for all ADS-112 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.
(R)
(R)
ISO 9001
R E G I S T E R E D
DS-0149F
10/96
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:sales@datel.com Data Sheet Fax Back: (508) 261-2857
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 Munchen, Germany Tel: 89-544334-0 DATEL KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-354-2025
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. The DATEL logo is a registered DATEL, Inc. trademark.

▲Up To Search▲

Price & Availability of ADS-112

	To Download ADS-112 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .