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Details, datasheet, quote on part number:AD7889
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Datasheet text preview:
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Preliminary Technical Information
FEATURES Fast 12-Bit ADC with 1.4 µs Conversion Time Up to 600 kSPS Throughput Rate (Mode A) Single Supply Operation On-Chip Track/Hold Amplifier Selection of Input Ranges: ±10 V or ±5 V for AD7889-1 0 V to +2.5 V or 0V to+5 V for AD7889-2 ±2.5 V for AD7889-3 High Speed Serial Interface Low Power, 60 mW typ
VREF 2½K
LC2MOS Single Supply, 12-Bit 600 kSPS ADC AD7889
FUNCTIONAL BLOCK DIAGRAM
VDD +2.5V REFERENCE
AD7889
RFS TRACK /HOLD 12-BIT ADC SDATA SCLK
VIN1 VIN2
SIGNAL SCALING
CONTROL LOGIC
STANDBY
CONVST CONTCLK 16/14B
AGND
DGND
GENERAL DESCRIPTION
The AD7889 is a high speed, low power, 12-bit A/D converter that operates from a single +5 V supply. The part contains a successive approximation ADC, an on-chip track/hold amplifier, an internal +2.5 V reference and on-chip versatile interface structures that allows serial communication to a microprocessor in a variety of operating modes. The part accepts an analog input range of ±10 V or ±5 V (AD7889-1), 0 V to +2.5 V or 0 V to +5V (AD7889-2) and ±2.5 V (AD7889-3). Overvoltage protection on the analog inputs for the AD7889-1 and AD7889-3 allows the input voltage to go to ±17 V or ±7 V respectively without damaging the ports. The AD7889 offers a choice of serial interface modes which allows direct connection to the serial ports of microcontrollers and digital signal processors. In addition to the traditional dc accuracy specifications such as linearity, full-scale and offset errors, the part is also specified for dynamic performance parameters including harmonic distortion and signal-to-noise ratio. The AD7889 is fabricated in Analog Devices Linear Compatible CMOS (LC2MOS) process, a mixed technology process that combines precision bipolar circuits with low power CMOS logic. It is available in a 16-pin, SSOP.
1. The AD7889 features a conversion time of 1.4µs (Mode A) and a track/hold acquisition time of 300ns. This allows a throughput rate for the part up to 600 kSPS. Modes C and D can be used to allow a throughput rate of 500kSPS. 2. The AD7889 operates from a single +5 V supply and consumes 60 mW typ making it ideal for low power and portable applications. 3. The part offers a high speed, serial interface for easy connection to microprocessors, microcontrollers and digital signal processors.
PRODUCT HIGHLIGHTS
REV. B
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. © Analog Devices, Inc., 1996 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 617/329-4700 Fax: 617/326-8703
AD7889SPECIFICATIONS (V T
Parameter DYNAMIC PERFORMANCE AD7889-1, AD7889-2 Signal to (Noise + Distortion) Ratio3 Total Harmonic Distortion3 Peak Harmonic or Spurious Noise3 Intermodulation Distortion3 2nd Order Terms 3rd Order Terms AD7889-3 Signal to (Noise + Distortion) Ratio3 Total Harmonic Distortion3 Peak Harmonic or Spurious Noise3 Intermodulation Distortion3 2nd Order Terms 3rd Order Terms DC ACCURACY Resolution Minimum Resolution for Which No Missing Codes Are Guaranteed Relative Accuracy3 Differential Nonlinearity3 Positive Full-Scale Error3 AD7889-1 Negative Full-Scale Error3 Bipolar Zero Error3 AD7889-3 Negative Full-Scale Error3 Bipolar Zero Error3 AD7889-2 Only Unipolar Offset Error3 ANALOG INPUT AD7889-1 Input Voltage Range Input Voltage Range Input Resistance AD7889-2 Input Voltage Range on VIN1 Input Voltage Range on VIN1 Input Current AD7889-3 Input Voltage Range on VIN1 Input Resistance REFERENCE OUTPUT/INPUT VREF Input Voltage Range Input Impedance Input Capacitance4 VREF Output Voltage VREF Error @ +25°C T MIN to TMAX VREF Temperature Coefficient VREF Output Impedance LOGIC INPUTS Input High Voltage, VINH Input Low Voltage, V INL Input Current, IIN Input Capacitance, CIN4 A Versions1 70 80 81 80 80 70 78 79 78 78 12 12 ±4 ±4 ±3 ±4 ±4 ±4 70 80 81 80 80 70 78 79 78 78 12 12 ±1 ±1 ±4 ±4 ±2 ±4 ±3 ±3
DD =
MAX
+5 V ± 5%, AGND = DGND = 0 V, REF IN = +2.5 V. All specifications TMIN to unless otherwise noted.)
S Version2 Units Test Conditions/Comments fIN = 100 kHz. f SAMPLE = 500 kSPS
B Versions
70 78 79 78 78
dB min dB max dB max dB max dB max dB min dB max dB max dB max dB max
fa = 49 kHz, fb = 50 kHz fIN = 100 kHz. f SAMPLE = 600 kSPS
fa = 49 kHz, fb = 50 kHz
12 12 ±1 ±1 ±5 ±5 ±3
Bits Bits LSB max LSB max LSB max LSB max LSB max LSB max LSB max
±4
LSB max
±10 ±5 25 0 to +5 0 to +2.5 10 ±2.5 2 2.375/2.625 1.6 10 2.5 ±10 ±20 25 5.5 2.4 0.8 ±10 10
±10 ±5 25 0 to +5 0 to +2.5 10 ±2.5 2 2.375/2.625 1.6 10 2.5 ±10 ±20 25 5.5 2.4 0.8 ±10 10
±10 ±5 25 0 to +5 0 to +2.5 50
Volts Volts k min Volts Volts nA max Volts k min
Input Applied to VIN1 with V IN2 Grounded Input Applied to VIN1 and VIN2 Input Applied to VIN1 with V IN2 Grounded Input Applied to VIN1 with V IN2 Grounded Input Applied to VIN1 and VIN2 Input Applied to VIN1
2.375/2.625 1.6 10 2.5 ±10 ±25 25 5.5 2.4 0.8 ±10 10
V min/V max k min pF max V nom mV max mV max ppm/°C typ k nom V min V max µA max pF max
2.5 V ± 5% Resistor Connected to Internal Reference Node
VDD = 5 V ± 5% VDD = 5 V ± 5% VIN = 0 V to VDD
REV. B
PRELIM. 7/97
2
Preliminary Technical Information
Parameter L O G I C OUTPUTS Output High Voltage, VOH Output Low Voltage, VOL Floating-State Leakage Current Floating-State Capacitance4 Output Coding AD7889-1 and AD7889-3 AD7889-2 CONVERSION RATE Conversion Time Conversion Time Conversion Time Track/Hold Acquisition Time3 POWER REQUIREMENTS VDD IDD5 Normal Operation Standby Mode6 AD7889-1, AD7889-2 AD7889-3 Power Dissipation5 Normal Operation Standby Mode6 AD7889-1, AD7889-2 AD7889-3 A Versions 1 B Versions S Version2 4.0 0.4 ±10 15 4.0 0.4 ±10 15 4.0 0.4 ±10 15 Units V min V max µA max pF max ISOURCE = 200 µA ISINK = 1.6 mA
AD7889
T e s t Conditions/Comments
2s Complement Straight (Natural) Binary 1.4 1.6 2.4 0.3 1.4 1.6 2.4 0.3 µs µs µs µs max max max max Mode A Modes C and D Mode B All Modes
+5 18 250 40 90 1.25 200
+5 18 250 40 90 1.25 200
+5 19 15 95 0.075
V nom mA max µA typ µA max mW max mW typ µW max
±5% for Specified Performance
V DD = +5 V. Typically 60 mW VDD = +5 V. Typically 50 µW
N OTES 1 Temperature ranges are as follows: A, B Versions: 40°C to +85°C; S Version: 55°C to +125°C. 2 S Version available on AD7889-1 and AD7889-2 only. 3 See Terminology. 4 Sample tested @ +25°C to ensure compliance. 5 These normal mode and standby mode currents are achieved with resistors (in the range 10 k to 100 k) to either DGND or VDD on Pins x, x, x a n d x. 6 A conversion should not be initiated on the part within 30 µs of exiting standby mode. Specifications subject to change without notice.
ABSOLUTE MAXIMUM RATINGS*
VDD to AGND . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to +7 V VDD to DGND . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to +7 V Analog Input Voltage to AGND AD7889-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±17 V AD7889-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +7 V AD7889-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±7 V Reference Input Voltage to AGND . . 0.3 V to VDD + 0.3 V Digital Input Voltage to DGND . . . . . 0.3 V to VDD + 0.3 V Digital Output Voltage to DGND . . . 0.3 V to VDD + 0.3 V Operating Temperature Range Commercial (A, B Versions) . . . . . . . . . . . 40°C to +85°C Extended (S Version) . . . . . . . . . . . . . . . 55°C to +125°C Storage Temperature Range . . . . . . . . . . . . 65°C to +150°C
(TA = +25°C unless otherwise noted)
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . +150°C SSOP Package, Power Dissipation. . . . . . . . . . . . . . 450 mW JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . . . 75°C/W Lead Temperature, Soldering Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . +215°C Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . +220°C
*
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those listed in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
REV. B
PRELIM. 7/97
3
AD7889 TIMING CHARACTERISTICS1, 2 (V
Parameter tCONV tA C Q Serial Interface t1 3 t2 3 t3 t4 t5 t6 t8 t9 t10 A, B Versions 1.4 1.6 300
DD
Preliminary Technical Information
= +5 V ± 5%, AGND = DGND = 0 V, REF IN = +2.5 V)
Units µs max µs max ns min Test Conditions/Comments Conversion Time for AD7889 (Mode A) Conversion Time for AD7889 (Modes C &D) Acquisition Time for AD7889 S Version 1.6
20 30 25 25 XX 20 25 25 XX
20 35 25 25 XX 20 25 25 XX
ns ns ns ns ns ns ns ns ns
min min min min min min max min min
SCLK Rising Edge to Data Valid Hold Time RFS Low to SCLK Falling Edge Setup Time SCLK High Pulse Width SCLK Low Pulse Width CONVST High to SCLK Falling Edge SCLK Rising Edge to RFS Rinsing Edge SCLK High Pulse Width (Mode B) SCLK Low Pulse Width (Mode B) CONVST High to RFS Falling Edge
1 2 3
NOTES
Sample tested at +25°C to ensure compliance. All input signals are measured with tr = tf = 1 ns (10% to 90% of +5 V) and timed from a voltage level of +1.6 V. See Figures 2a - 2d. Measured with the load circuit of Figure 1 and defined as the time required for an output to cross 0.8 V or 2.4 V.
Specifications subject to change without notice.
1.6mA
TO OUTPUT PIN 50pF 200µA
+1.6V
Figure 1. Load Circuit for Access Time and Bus Relinquish Time CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD7889 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
4
REV. B
PRELIM. 7/97
Preliminary Technical Information
ORDERING GUIDE
AD7889
Sample Rate 600 kSPS 6 0 0 kSPS 5 0 0 kSPS 5 0 0 kSPS Relative Accuracy ± 1 LSB ± 1 LSB Temperature Range 40°C to +85°C 40°C to +85°C 40°C to +85°C 40°C to +85°C Package O p t i o n1 RS-16 RS-16 RS-16 RS-16
Model AD7889ARS-1 AD7889BRS-1 AD7889ARS-2 AD7889ARS-3 EVAL-AD7889-1CB2 EVAL-AD7889-2CB2 EVAL-AD7889-3CB2 EVAL-CONTROL BOARD3
Input Range ±5 V or ±10 V ±5 V or ±10 V 0 V to 2.5 V or 0 V to 5 V ±2.5 V Evaluation Board Evaluation Board Evaluation Board Controller Board
NOTES 1R S= SSOP. 2These boards can be used as stand-alone evaluation boards or in conjunction with the EVAL-CONTROL BOARD for evaluation/demonstration purposes. 3This board is a complete unit allowing a PC to control and communicate with all Analog Devices evaluation boards ending in the CB designators.
PIN CONFIGURATION SSOP
VIN2 VIN1 A VD D VREF AGND STANDBY RFS SDATA
1 2 3 4 5 6 7 8
16 15
AD7889 TOP VIEW
14 13
(Not to Scale) 12 11 10 9
AGND CONTCLK 16/14B IDLEHI CONVST DGND DVDD SCLK
REV. B
PRELIM. 7/97
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