AD7538 Analog Devices, AD7538 Datasheet
AD7538
Specifications of AD7538
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AD7538 Summary of contents
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... Low Cost. The AD7538, with its 14-bit dynamic range, affords a low cost solution for 12-bit system upgrades. 3. Small Package Size. The AD7538 is packaged in a small 24-pin, 0.3" DIP and a 24-pin SOIC. 4. Low Output Leakage. By tying V (Pin 24 negative voltage possible to SS achieve a low output leakage current at high temperatures ...
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... Digital Section ............................................................................ 10 Unipolar Binary Operation (2-Quadrant Multiplication) .... 10 Bipolar Operation (4-Quadrant Multiplication) .................... 11 Low Leakage Configuration ...................................................... 11 Programmable Gain Amplifier ................................................. 12 Application Hints ........................................................................... 13 Output Offset .............................................................................. 13 General Ground Management .................................................. 13 Microprocessor Interfacing ....................................................... 13 AD7538-to-8086 Interface ........................................................ 13 AD7538-to-MC68000 Interface ............................................... 13 Digital Feedthrough ................................................................... 14 Outline Dimensions ....................................................................... 15 Ordering Guide .......................................................................... 16 Rev Page ...
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... V, the device is fully functional with degraded specifications. DD Rev Page AD7538 unless otherwise noted. MIN MAX Unit Test Conditions/Comments Bits LSB max All grades guaranteed monotonic LSB max Over temperature ...
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... AD7538 AC PERFORMANCE CHARACTERISTICS These characteristics are included for design guidance only and are not subject to test −300 mV, output amplifier is SS Table Parameter T A Output Current Settling Time 1.5 Digital-to-Analog Glitch Impulse 20 Multiplying Feedthrough Error 3 Power Supply Rejection Δ ...
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... TO 90 20ns TIMING MEASUREMENT REFERENCE LEVEL LDAC IS ACTIVATED PRIOR TO THE RISING EDGE OF WR, t THEN IT MUST STAY LOW FOR OR LONGER AFTER WR GOES HIGH. 3 Figure 2. Timing Diagram Rev Page AD7538 ...
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... AD7538 ABSOLUTE MAXIMUM RATINGS T = +25°C unless, otherwise stated. A Table 4. Parameter V (Pin 23) to DGND DD V (Pin 24) to AGND SS V (Pin 1) to AGND REF V (Pin 2) to AGND RFB Digital Input Voltage (Pins 6 to 22) to DGND V to DGND PIN3 AGND to DGND Power Dissipation (Any Package) To 75° ...
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... DB9 DB4 10 15 DB8 DB5 11 14 DB7 DB6 12 13 Figure 3. Pin Configuration LDAC WR Operation 1 0 Load input register Load DAC register from input register Input and DAC registers are transparent operation operation. Rev Page AD7538 ...
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... AD7538 TERMINOLOGY Relative Accuracy Relative accuracy or endpoint nonlinearity is a measure of the maximum deviation from a straight line passing through the endpoints of the DAC transfer function measured after adjusting for zero error and full-scale error and is normally expressed in least significant bits percentage of full- scale reading ...
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... DAC SECTION Figure 4 shows a simplified circuit diagram for the AD7538 DAC section. The three MSBs of the 14-bit data word are decoded to drive the seven switches (A to G). The 11 LSBs of the data word consist of an R-2R ladder operated in a current steering configuration. The R-2R ladder current is ⅛ of the total reference input current. ⅞ ...
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... For high temperature operation, resistors and potentiometers should have a low temperature coefficient. In many applications, because of the excellent gain TC and gain error specifications of the AD7538, gain error trimming is not necessary. In fixed reference applications, full scale can also be adjusted by omitting R1 and R2 and trimming the reference voltage magnitude ...
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... Figure 8 Binary Number In DAC Register MSB 11 1111 1111 1111 = O 10 0000 0000 0001 10 0000 0000 0000 01 1111 1111 1111 or by varying the IN 00 0000 0000 0000 Figure 7. Graph of Typical Leakage Current vs. Temperature for AD7538 22Ω ...
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... AD7538 PROGRAMMABLE GAIN AMPLIFIER The circuit shown in Figure 9 provides a programmable gain amplifier (PGA the DAC behaves as a programmable resistance and thus allows the circuit gain to be digitally controlled. DIGITAL INPUT OUT AD7538 GND NOTES 1 ...
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... GENERAL GROUND MANAGEMENT Because the AD7538 is specified for high accuracy impor- tant to use a proper grounding technique transient voltages between AGND and DGND can cause noise injection into the analog output. The simplest method of ensuring that voltages at AGND and DGND are equal is to tie AGND and DGND together at the AD7538 ...
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... AD7538 DIGITAL FEEDTHROUGH The digital inputs to the AD7538 are directly connected to the microprocessor bus in the preceding interface configurations. These inputs are constantly changing even when the device is not selected. The high frequency logic activity on the bus can feed through the DAC package capacitance to show up as noise on the analog output ...
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... MIN 0.100 SEATING 0.070 (1.78) PLANE (2.54) 0.030 (0.76) BSC Figure 15. 24-Lead Ceramic Dual In-Line Package [CERDIP] (Q-24-1) Dimensions shown in inches and (millimeters) Rev Page 0.325 (8.26) 0.310 (7.87) 0.300 (7.62) 0.195 (4.95) MAX 0.130 (3.30) 0.115 (2.92) 0.014 (0.36) 0.010 (0.25) 0.008 (0.20) 0.430 (10.92) MAX 0.320 (8.13) 0.290 (7.37) 0.015 (0.38) 0.008 (0.20) 15° 0° AD7538 ...
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... AD7538JRZ-REEL 0°C to +70°C AD7538KR 0°C to +70°C AD7538KR-REEL 0°C to +70°C 1 AD7538KRZ 0°C to +70°C 1 AD7538KRZ-REEL 0°C to +70°C AD7538AQ −25°C to +85°C AD7538BQ −25°C to +85°C AD7538SQ −55°C to +125°C AD7538TQ −55°C to +125° RoHS Compliant Part. ...