® ®
REGISTER
REGISTER
3-STATE OUTPUT REGISTER
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
ADS-117
12-Bit, 2MHz, Low-Power
Sampling A/D Converters
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.
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 ADS-117
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.
+10V REF. 21
S2
S/H
S1
BUFFER
BIPOLAR 20
ANALOG INPUT 19
–
+
INPUT/OUTPUT CONNECTIONS
PIN FUNCTION PIN FUNCTION
1 BIT 12 (LSB) 24 –15V SUPPLY
2 BIT 11 23 ANALOG GROUND
3 BIT 10 22 +15V SUPPLY
4 BIT 9 21 +10V REFERENCE
5 BIT 8 20 BIPOLAR
6 BIT 7 19 ANALOG INPUT
7 BIT 6 18 COMP BIN
8 BIT 5 17 ENABLE (1-12)
9 BIT 4 16 START CONVERT
10 BIT 3 15 EOC
11 BIT 2 14 DIGITAL GROUND
12 BIT 1 (MSB) 13 +5V SUPPLY
DAC
REF
FLASH
ADC
17 ENABLE (1-12)
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)
COMP BIN 18
EOC 15
TIMING AND
CONTROL LOGIC
13
14
22
23
24
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 LIMITS UNITS
+15V Supply (Pin 22) 0 to +16 Volts
–15V Supply (Pin 24) 0 to –16 Volts
+5V Supply (Pin 13) 0 to +6.0 Volts
Digital Inputs (Pin 16, 17, 18) –0.3 to +V
DD +0.3 Volts
Analog Input (Pin 19) –9 to +15 Volts
Lead Temp. (10 seconds) +300 °C
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 — ±5 — Volts
Unipolar — 0 to +10 — Volts
Input Impedence 4.5 5 — kΩ
Input Capacitance — 6 15 pF
DIGITAL INPUTS
Logic Levels
Logic "1" +2.0 — — Volts
Logic "0" — — +0.8 Volts
Logic Loading "1" — — +5 µA
Logic Loading "0" — — –600 µA
PERFORMANCE
Resolution 12 Bits
No Missing Codes
in = 1MHz) 0 to +70°C
(12 Bits; f
Integral Non-Linearity
0°C to +70°C — ±1/2 ±2 LSB
–55°C to +125°C — ±1 ±3 LSB
Differential Non-Linearity
0°C to +70°C — ±1/2 ±0.95 LSB
–55°C to +125°C — ±1 +1.5 LSB
Full Scale Absolute Accuracy
(see Tech Note 1)
0°C to +70°C — ±0.13 ±0.44 %FSR
–55°C to +125°C — ±0.25 ±0.73 %FSR
Unipolar/Bipolar Zero Error
0°C to +70°C (see Tech Note 1) — ±0.07 ±0.27 %FSR
–55°C to +125°C — ±0.22 ±0.73 %FSR
Bipolar Offset Error
0°C to +70°C (see Tech Note 1) — ±0.1 ±0.38 %FSR
–55°C to +125°C — ±0.53 ±0.73 %FSR
Gain Error (see Tech Note 1)
0°C to +70°C — ±0.1 ±0.38 %
–55°C to +125°C — ±0.53 ±0.73 %
Internal Reference Voltage
0°C to +70°C +9.97 +10.0 +10.03 Volts
–55°C to +125°C +9.95 — +10.05 Volts
External Current — — 1.5 mA
DYNAMIC PERFORMANCE
Spurious Free Dynamic
Range (–0.5dB) ➁
dc to 100kHz — –81 — dB
100kHz to 500kHz — –75 –70 dB
500kHz to 1MHz — –70 — dB
Total Harm. Distort. (–0.5dB)
dc to 100kHz — –78 — dB
100kHz to 500kHz — –73 –68 dB
500kHz to 1MHz — –71 — dB
Input Bandwith (–3dB)
Small Signal (–20dB input) 8 10 — MHz
Large Signal (–0.5dB input) 7 9 — MHz
Feedthrough (1MHz) –72 –74 — dB
➀ See Table 1 also
➁ Same specifications for in-band harmonics.
DYNAMIC PERF. (cont) MIN. TYP. MAX. UNITS
SNR (wo/distortion, –0.5dB)
dc to 100kHz
0°C to +70°C — 72 — dB
–55°C to +125°C — 72 — dB
100kHz to 500kHz
0°C to +70°C 65 70 — dB
–55°C to +125°C 65 70 — dB
500kHz to 1MHz
0°C to +70°C — 70 — dB
–55°C to +125°C — 70 — dB
SNR (and distort., –0.5dB) ➂
dc to 100kHz
0°C to +70°C — 70 — dB
–55°C to +125°C — 69 — dB
100kHz to 500kHz
0°C to +70°C 64 70 — dB
–55°C to +125°C 62 69 — dB
500kHz to 1MHz
0°C to +70°C — 69 — dB
–55°C to +125°C — 69 — dB
Two-tone Intermodulation
990kHz, f
in = 970kHz,
s = 2Mhz,
Distortion (f
–0.5dB) — –68 — dB
Slew Rate — ±210 — V/µs
Effect. Aperture Delay Time — — 16 ns
Overvoltage Recovery
Time; 20% — — 500 ns
S/H Acq. Time, (to ±0.01%)
0 to +70°C — 155 165 ns
–55°C to +125°C — 160 170 ns
Conversion Rate 2 — — MHz
OUTPUTS
Output Coding
Pin 18 High
Pin 18 Low
Logic Level
Staight binary/Offset binary
Complementary binary
Complementary offset binary
Logic "1" +2.4 — — Volts
Logic "0" — — +0.4 Volts
Logic Loading "1" — — –160 µA
Logic Loading "0" — — +6.4 mA
POWER REQUIREMENTS
Power Supply Ranges ➃
+15V Supply +14.25 +15.0 +15.75 Volts
–15V Supply –14.25 –15.0 –15.75 Volts
+5V Supply +4.75 +5.0 +5.25 Volts
Power Supply Current
+15V Supply — +48 +58 mA
–15V Supply — –35 –45 mA
+5V Supply — +75 +85 mA
Power Dissipation — 1.6 1.9 Watts
Power Supply Rejection — — ±0.07 %FSR%V
PHYSICAL/ENVIRONMENTAL
Operating Temp. Range, Case
ADS-117MC 0 — +70 °C
ADS-117MM, 883 –55 — +125 °C
Storage Temperature Range –65 — +150 °C
Thermal Impedance
θjc — 3 — °C/W
θca — 23 — °C/W
Package Type 24-pin, metal-sealed, ceramic DDIP
Weight 0.42 ounces (12 grams)
➂ Effective bits is equal to:
(SNR + Distortion) – 1.76 + 20 log
Full Scale Amplitude
Actual Input Amplitude
6.02
➃ For ±12V, +5V operation, contact DATEL
2