DAC8248 Analog Devices, DAC8248 Datasheet
DAC8248
Specifications of DAC8248
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DAC8248 Summary of contents
Page 1
... The DAC consists of two thin-film R-2R resistor ladder networks, two 12-bit, two 8-bit, and two 4-bit data regis- ters, and control logic circuitry. Separate reference input and feedback resistors are provided for each DAC. The DAC8248 FUNCTIONAL BLOCK DIAGRAM One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. ...
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... OUT A OUT + REF A Symbol Conditions N INL DAC8248A/E/G DAC8248F/H DNL All Grades are Guaranteed Monotonic G DAC8248A/E FSE DAC8248G DAC8248F/H TCG (Notes All Digital Inputs = +25 C LKG Full Temperature Range A R (Note 4) REF R REF R REF ...
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... MAX = V = +10 V; OUT A, OUT B load = 100 REF A REF +12 V with +5 V CMOS logic levels and Burn-In Circuit –3– DAC8248 DAC8248 Units – +125 C All Temps (Note 10) 180 80 ns min min 220 80 ns min ...
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... 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 DAC8248 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 ...
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... DD –5– DAC8248 13. NC 14. DB1 15. DB0(LSB) 16. RESET 17. LSB/MSB 18. DAC A/DAC B 19. LDAC 20 22. V REF B 23 24. I OUT DAC8248G Limit Units 1 LSB max 1 LSB max 4 LSB max 50 nA max 8/15 k min/k max 1 % max 2.4 V min 13.5 V min 0.8 V max 1.5 V max 1 ...
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... DAC8248 –Typical Performance Characteristics Channel-to-Channel Matching (DAC A & B are Superimposed) Nonlinearity vs. V REF Nonlinearity vs. Code (DAC A & B are Superimposed) Differential Nonlinearity vs. V REF Nonlinearity vs. V REF Nonlinearity vs. Code – +25 C, +125 C for DAC A & B (All Superimposed) –6– ...
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... Full-Scale Gain Error vs. Temperature Supply Current vs. Logic Input Voltage Output Leakage Current vs. Temperature REV. B Logic Input Threshold Voltage vs. Supply Voltage ( Multiplying Mode Frequency Response vs. Digital Code Analog Crosstalk vs. Frequency –7– DAC8248 Supply Current vs. Temperature ...
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... GENERAL CIRCUIT DESCRIPTION CONVERTER SECTION n ) that the The DAC8248 incorporates two multiplying 12-bit current out- put CMOS digital-to-analog converters on one monolithic chip. It contains two highly stable thin-film R-2R resistor ladder net- works, two 12-bit DAC registers, two 8-bit input registers, and two 4-bit input registers ...
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... The DAC8248 may be operated with any supply voltage between the range +15 V and still perform to data sheet limits. The DAC8248’s 8-bit wide data port loads a 12-bit word in two bytes: 8-bits then 4-bits (or 4-bits first then 8-bits, at users dis- ) and the R-2R FB cretion right justified data format ...
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... DAC8248 Figure 4. Four Cycle Update Timing Diagram Figure 5. Five Cycle Update Timing Diagram –10– REV. B ...
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... DACs in a multiple DAC system can be updated simultaneously. RESET The DAC8248 comes with a RESET pin that is useful in system calibration cycles and/or during system power-up. All registers are reset to zero when RESET is low, and latched at zero on the rising edge of the RESET signal when WRITE is high ...
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... APPLICATIONS INFORMATION UNIPOLAR OPERATION Figure 7 shows a simple unipolar (2-quadrant multiplication) circuit using the DAC8248 and OP270 dual op amp (use two OP42s for applications requiring higher speeds), and Table I shows the corresponding code table. Resistors R1, R2, and R3, R4 are used only if full-scale gain adjustments are required. ...
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... BIPOLAR OPERATION The bipolar (offset binary) 4-quadrant configuration using the DAC8248 is shown in Figure 8, and the corresponding code is shown in Table II. The circuit makes use of the OP470, a quad op amp (use four OP42s for applications requiring higher speeds). ...
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... Back-to-back Schottky di- odes should then be connected between AGND and DGND. POWER SUPPLY DECOUPLING Power supplies used with the DAC8248 should be well filtered and regulated. Local supply decoupling consisting tantalum capacitor in parallel with a 0.1 F ceramic is highly recommended ...
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... Figure 10. Single Supply Operation (Voltage Switching Mode) Figure 11. Digitally-Programmable Window Detector (Upper/Lower Limit Detector) MICROPROCESSOR INTERFACE CIRCUITS The DAC8248s versatile loading structure allows direct inter- face to an 8-bit microprocessor. Its simplicity reduces the num- ber of required glue logic components. Figures 12 and 13 show the DAC8248 interface configurations with the MC6809 and MC68008 microprocessors ...
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... PIN 1 0.060 (1.52) 0.210 0.015 (0.38) (5.33) MAX 0.200 (5.05) 0.125 (3.18) 0.100 (2.54) 0.022 (0.558) 0.070 (1.77) SEATING BSC PLANE 0.014 (0.356) 0.045 (1.15) Figure 13. DAC8248 to MC68008 Interface OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 24-Lead Cerdip (Q-24) 0.005 (0.13) MIN 0.098 (2.49) MAX 24 13 0.310 (7.87) 0.220 (5.59 PIN 1 0.060 (1.52) 1.280 (32.51) MAX ...