ADADC85-12 Analog Devices Inc, ADADC85-12 Datasheet
ADADC85-12
Specifications of ADADC85-12
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ADADC85-12 Summary of contents
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FEATURES PERFORMANCE Complete 12-bit A/D converter with reference and clock Fast successive approximation conversion: 10 µ µs Buried Zener reference for long-term stability and low Gain TC: 10 ppm/°C Max nonlinearity: < ±0.012% Low power: 880 mW typ ...
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AD ADC84/AD ADC85 TABLE OF CONTENTS Specifications..................................................................................... 3 Typical Performance Characteristics ............................................. 5 Functional Description .................................................................... 6 Offset Adjustment ........................................................................ 6 Gain Adjustment........................................................................... 6 Theory of Operation .................................................................... 6 Timing............................................................................................ 6 Digital Output Data ..................................................................... 7 REVISION HISTORY Revision B ...
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SPECIFICATIONS Table 1. Typical @ 25°C, ±15 V and +5 V, unless otherwise noted Model RESOLUTION ANALOG INPUTS Voltage Ranges Bipolar Unipolar Impedance (Direct Input ±2 +10 V, ±5 V ±10 ...
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AD ADC84/AD ADC85 Model DIGITAL OUTPUT (All Codes Complementary) Parallel Output Codes 7 Unipolar Bipolar Output Drive Status Status Output Drive Internal Clock Clock Output Drive Frequency INTERNAL REFERENCE VOLTAGE Maximum External Current (with No Degradation of Specifications) Tempco of ...
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TYPICAL PERFORMANCE CHARACTERISTICS Figure 2. Linearity Error vs. Conversion Speed Figure 3. Gain Drift Error (%FSR) vs. Temperature Figure 4. Change in Differential Linearity vs. Conversion Speed Figure 5. Conversion Speed vs. Control Voltage Rev Page 5 of ...
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AD ADC84/AD ADC85 FUNCTIONAL DESCRIPTION OFFSET ADJUSTMENT The zero adjust circuit consists of a potentiometer connected across ±V with its slider connected through a 1.8 MΩ resistor S to Comparator Input Pin 22 for all ranges. As shown in Figure ...
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NOTES 1. THE CONVERT START PULSE WIDTH IS 100ns MIN AND MUST REMAIN LOW DURING A CONVERSION. THE CONVERSION IS INITIATED BY THE “TRAILING EDGE” OF THE CONVERT COMMAND. 2. 10μs FOR 12 BITS (AD ADC84/AD ADC85). 3. MSB DECISION. ...
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AD ADC84/AD ADC85 INPUT SCALING The AD ADC84/AD ADC85 inputs should be scaled as close to the maximum input signal range as possible in order to utilize the maximum signal resolution of the A/D converter. Connect the input signal as ...
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CALIBRATION External ZERO ADJ and GAIN ADJ potentiometers, connected as shown in Figure 12 and Figure 13, are used for device calibration. To prevent interaction of these two adjustments, zero is always adjusted first and then gain. Zero is adjusted ...
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AD ADC84/AD ADC85 CLOCK RATE CONTROL ALTERNATE CONNECTIONS If adjustment of the CLOCK RATE is desired for faster conver- sion speeds, the CLOCK RATE CONTROL may be connected to an external multiturn trim potentiometer with a TCR of ±100 ppm/°C ...
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... ORDERING GUIDE 1 Model Operation Voltage (V) 2 ADADC84-12 ±15 2 ADADC84Z-12 ±12 ADADC85C-12 2 ±15 ADADC85-12 ±15 2 ADADC85Z-12 ±12 ADADC85S-12 ±15 ADADC85SZ-12 ±12 ADADC85S12/883B ±15 ADADC85SZ12/883 ±12 1 For complete model number, suffixes must be added for “Z” option (±12 V operation), linearity. The following guide shows the proper suffix order: AD ADC(*)(**)-(***), where * = Model Number Version Designator, and *** = Linearity ...
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AD ADC84/AD ADC85 NOTES © 2003 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C03262–0–11/03(B) Rev Page ...