(R) ADC-228A (R) 8-Bit, 20MHz, Complete Flash A/D Converter PRODUCT OVERVIEW The ADC-228A combines analog front-end circuitry and a flash A/D converter to digitize high-speed analog signals at a rate of 20 million samples per second. The ADC-228A contains an 8-bit, 20MHz, flash A/D, a wideband analog input buffer, a precision voltage reference, temperature compensation circuitry, reference trims, and a three-state output buffer in a 24-pin package. The ADC-228A offers significant savings by INPUT/OUTPUT CONNECTIONS FUNCTION Pin +5V SUPPLY 24 Pin 1 FEATURES combining all of the circuitry in a single package. Valuable board real estate is saved, and design time and manufacturing costs are reduced. The ADC-228A is housed in a 24-pin ceramic DDIP package and is available in the commercial, 0 to +70C, or military, -55 to +125C, temperature ranges. A MIL-STD-883 version is also available. Operation is from 15V and +5V power supplies. FUNCTION BIT 8 (LSB) 2 GROUND 23 3 +5V REFERENCE OUT 22 BIT 7 BIT 6 21 BIT 5 NO CONNECTION 8-Bit flash A/D converter 4 GROUND 20MHz sampling rate 5 ANALOG INPUT 20 6 GROUND 19 +15V SUPPLY 7 GROUND 18 CLOCK INPUT Complete support circuitry Low power, 900mW 8 NO CONNECTION 17 BIT 4 Sample-hold not required 9 NO CONNECTION 16 BIT 3 10 -15V SUPPLY 15 BIT 2 11 CS1 14 BIT 1 (MSB) 12 CS2 13 NO CONNECTION Three-state outputs MIL-STD-883 versions CS1 11 13 NO CONNECTION CS2 12 NO CONNECTION 8 NO CONNECTION 9 CLOCK 18 20 NO CONNECTION 14 BIT 1 (MSB) ANALOG INPUT 5 INPUT BUFFER LINEARIZATION & TEMPERATURE COMPENSATION NETWORK +15V SUPPLY 19 -15V SUPPLY 10 15 BIT 2 16 BIT 3 8-BIT 20MHz FLASH CONVERTER TRI-STATE BUFFER 17 BIT 4 21 BIT 5 22 BIT 6 23 BIT 7 24 BIT 8 (LSB) GROUND 7 GROUND 6 3 +5V REF. OUT VOLTAGE REFERENCE NETWORK GROUND 4 GROUND 2 +5V SUPPLY 1 Figure 1. Functional Block Diagram DATEL * 11 Cabot Boulevard, Mansfield, MA 02048-1151 USA * Tel: (508) 339-3000 * www.datel.com 31 Mar 2011 * e-mail: help@datel.com ADC-228A.B02 Page 1 of 4 (R) ADC-228A (R) 8-Bit, 20MHz, Complete Flash A/D Converter PERFORMANCE ABSOLUTE MAXIMUM RATINGS PARAMETER Power Supply Voltage, Digital Inputs, Pins 8,9,11,12,18 Analog Input, Pin 5 Digital Outputs Pin 1 Pin 19 Pin 10 -0.5 to +5.5V LIMITS -0.3 to +7V -0.3 to +18V +0.3 to -18V -3.8 to +6.6V -0.5 to +5.5V (short circuit protected to ground) Lead Temp. (10 seconds) Gain error Full Scale Absolute Accuracy Differential Gain Differential Phase Aperture Delay Aperture Jitter No Missing Codes Power Supply Rejection MIN. TYP. MAX. UNITS -- -- -- -- -- -- 0.5 0.5 2 1 8 50 1.5 1.5 -- -- -- -- LSB LSB % deg. ns ps Over the operating temperature range 0.02% FSR/%VS maximum +300C DYNAMIC PERFORMANCE FUNCTIONAL SPECIFICATIONS (Apply over the operating temperature range with 20MHz clock and 15V and +5V power supply voltages, unless otherwise specified.) ANALOG INPUTS Single-Ended, Non-Isolated Input Range, dc-20MHz Input Resistance Input Capacitance MIN. TYP. MAX. UNITS 0 1.95 -- -- 2 5 +5.0 -- 10 Volts k pF +2.0 -- -- -- -- +0.8 Volts Volts -- -- -- -- +160 -0.5 A mA 20 20 -- -- -- -- ns ns DIGITAL INPUTS Logic Levels Logic 1 Logic 0 Logic Loading Logic 1 Logic 0 Clock Pulse Widths "High" "Low" Coding Resolution Logic Levels Logic 1 Logic 0 Logic Loading Logic 1 Logic 0 Output Data Valid Delay From Rising Edge Output Hold Time DIGITAL OUTPUTS Straight Binary 8 Bits Total Harm. Distortion, -0.5dB DC to 2.5 MHz 2.5 MHz to 5 MHz 5 MHz to 10 MHz Signal-to-Noise Ratio and Distortion, -0.5dB DC to 2.5 MHz 2.5 MHz to 5 MHz 5 MHz to 10 MHz Signal-to-Noise Ratio w/o Distortion, -0.5 dB DC to 2.5 MHz 2.5 MHz to 5 MHz 5 MHz to 10 MHz Effective Bits, -0.5dB DC to 2.5 MHz 2.5 MHz to 5 MHz 5 MHz to 10 MHz Input Bandwidth Large Signal (-3dB) Small Signal (-20dB) DATEL -55 -49 -39 -53 -44 -36 dB dB dB 44 41 35 49 46 38 -- -- -- dB dB dB 45 44 42 48 49 45 -- -- -- dB dB dB 7.1 6.8 5.6 7.75 7.4 6.1 -- -- -- Bits Bits Bits 15 40 -- -- -- -- MHz MHz +11 -11 +4.75 +15 -15 +5 +15.75 -15.75 +5.25 Volts Volts Volts -- -- -- +12 -13 +70 +20 -20 +80 mA mA mA -- 0.7 0.9 Watts POWER SUPPLY +2.4 -- -- -- -- +0.4 Volts Volts -- -- -- -- -1 +1 mA mA -- 6 -- -- 40 -- ns ns Power Supply Range +15V Supply -15V Supply +5V Supply Power Supply Current +15V Supply -15V Supply +5V Supply Power Dissipation 15V, +5V Nominal PHYSICAL/ENVIRONMENTAL PERFORMANCE Sampling Rate Differential Linearity Code Transitions, +25C 0 to +70C -55 to +125C Integral Linearity, +25C End-point Best-fit Line Over Temperature End-point Best-fit Line Zero-Scale Offset Code "0" to "1" Transition +25C -55 to +125C -- -- -- 20 -- -- MHz -- -- -- 0.5 0.5 0.5 0.75 0.75 0.85 LSB LSB LSB -- -- -- -- 0.5 0.35 -- -- 1 0.75 1.75 1 LSB LSB LSB LSB -- -- 0.5 0.5 1 1.5 LSB LSB * Operating Temp. Range, Case ADC-228AMC ADC-228AMM, ADC-228A/883 Storage Temp. Range Package Type Weight 0 to +70C -55 to +125C -65 to +150C 24-pin, ceramic DDIP 0.3 ounces (8.5 grams) Footnotes: At full power input and chip selects enabled. For 10-step, 40 IRE NTSC ramp test. 11 Cabot Boulevard, Mansfield, MA 02048-1151 USA * Tel: (508) 339-3000 * www.datel.com 31 Mar 2011 * e-mail: help@datel.com ADC-228A.B02 Page 2 of 4 (R) ADC-228A (R) 8-Bit, 20MHz, Complete Flash A/D Converter TECHNICAL NOTES 1. Rated performance requires using good high-frequency techniques. The analog and digital ground pins are connected to each other internally. Avoid ground related problems by connecting the grounds to one point, the ground plane beneath the converter. Due to the inductance and resistance of the power supply return paths, return the analog and digital ground separately to the power supplies. 2. Bypass all the analog and digital supplies and the +5V REFERENCE (pin 3) to ground with a 4.7F, 25V tantalum electrolytic capacitor in parallel with a 0.1F ceramic capacitor. Table 1. ADC-228A Unipolar Output Coding Table 2. Chip Select Truth Table ANALOG INPUT CODE STRAIGHT BIN. +4.96V +FS - 1 LSB 1111 1110 +3.75V + 3/4 FS 1100 0000 +2.50V + 1/2 FS 1000 0000 +1.25V + 1/4 FS 0100 0000 +0.02V + 1 LSB 0000 0001 0.00V ZERO 0000 0000 CS1 Pin 11 Bits 1-8 0 0 Three State Mode 0 1 Three State Mode 1 0 Data Outputted 1 1 Three State Mode SAMPLE N+1 SAMPLE N CLOCK CS2 Pin 12 SAMPLE N+2 OUTPUT DELAY DATA N DIGITAL OUTPUT DATA N+2 DATA N+1 OUTPUT HOLD TIME Figure 2. ADC-228A Timing Diagram -15V +5V 0.1F 4.7F 0.1F + 1 10 + 4.7F 14 15 16 17 21 CS1 11 ADC-228A 22 CS1 12 23 24 CLOCK 18 ANALOG INPUT B1 (MSB) B2 B3 B4 B5 B6 B7 B8 (LSB) 8, 9, 13, 20 VIN 5 51 3 *Optional * Use optional resistor only if amp is not used to drive input. R = VEE /1.667mA 2, 4, 6, 7 19 9k 0.1F + NO CONNECTION +5V REFERENCE OUT + 0.1F 4.7F 4.7F +15V Figure 3. ADC-228A Typical Connections DATEL * 11 Cabot Boulevard, Mansfield, MA 02048-1151 USA * Tel: (508) 339-3000 * www.datel.com 31 Mar 2011 * e-mail: help@datel.com ADC-228A.B02 Page 3 of 4 (R) ADC-228A (R) 8-Bit, 20MHz, Complete Flash A/D Converter 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 Lead Material: Kovar alloy 0.80 MAX. (20.32) 1 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) 0.200 MAX. (5.080) +0.002 0.010 -0.001 (0.254) 0.190 MAX. (4.826) 0.100 (2.540) 0.018 0.002 (0.457) 0.040 (1.016) SEATING PLANE 0.025 (0.635) 0.100 (2.540) 0.600 0.010 (15.240) ORDERING INFORMATION MODEL ADC-228AMC ADC-228AMM ADC-228A/883 * TEMPERATURE RANGE 0 to +70C -55 to +125C -55 to +105C SAMPLING RATE 20MSPS 20MSPS 15MSPS Receptacle for PC board mounting can be ordered through AMP Inc., part # 3-331272-8 (component lead socket), 24 required. Contact DATEL for 883 product specifications * DATEL's initial qualification was done at 15MSPS and as a Mil-STD-883 Class G product per customer request. Mil-STD-883 Class G allows for a reduced temperature range (-55C to +105C) that applies to this device. Contact DATEL if a 20MSPS rate or a Mil-STD-883 Class H (-55C to +125C) temperature range is desired. DATEL 11 Cabot Boulevard, Mansfield, MA 02048-1151 USA . 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. ITAR and ISO 9001/14001 REGISTERED www.datel.com * e-mail: help@datel.com 31 Mar 2011 ADC-228A.B02 Page 4 of 4