AD7245A Analog Devices, AD7245A Datasheet
AD7245A
Specifications of AD7245A
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AD7245A Summary of contents
Page 1
... For both parts, an asynchronous LDAC signal transfers data from the input latch to the DAC latch and updates the analog output. The AD7245A also has a CLR signal on the DAC latch which allows features such as power-on reset to be implemented. The on-chip 5 V buried Zener diode provides a low noise, tem- perature compensated reference for the DAC ...
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... AD7245A/AD7248A–SPECIFICATIONS AGND = DGND = 100 pF. All specifications Parameter STATIC PERFORMANCE Resolution 3 Relative Accuracy @ 25° MIN MAX MIN MAX 3 Differential Nonlinearity 3 Unipolar Offset Error @ 25° MIN MAX 3 Bipolar Zero Error @ 25° MIN MAX 3, 6 DAC Gain Error ...
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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 AD7245A/AD7248A 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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... DAC and output amplifier present for all codes and is measured with a code of 2048 (decimal) in the DAC register. SINGLE SUPPLY LINEARITY AND GAIN ERROR The output amplifier of the AD7245A/AD7248A can have a Relative Package true negative offset even when the part is operated from a single ...
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... CONNECT AD7245A/AD7248A Description Write Input (Active LOW). This is used in conjunction with CS to write data into the input latch of the AD7245A. Load DAC Input (Active LOW). This is an asynchronous input which when active transfers data from the input latch to the DAC latch. ...
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... AD7245A/AD7248A Pin Mnemonic Description l V Negative Supply Voltage (0 V for single SS supply operation Bipolar Offset Resistor. This provides OFS access to the on-chip application resistors and allows different output voltage ranges. 3 REF OUT Reference Output. The on-chip reference is provided at this pin and is used when configuring the part for bipolar outputs ...
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... 100mV p-p SIGNAL 0 20k 50k 50 POWER SUPPLY DECOUPLING CAPACITORS ARE 10 F AND 0.1 F 100 AD7245A/AD7248A – TEMPERATURE – C OUTPUT WITH ALL DECOUPLING 0s ON DAC NO DECOUPLING OUTPUT WITH ALL DECOUPLING 1s ON DAC NO DECOUPLING = 15V WITH 100 ...
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... DAC. Most of the impulse is actually as a result of feedthrough across the package. INTERFACE LOGIC INFORMATION—AD7245A Table I shows the truth table for AD7245A operation. The part contains two 12-bit latches, an input latch and a DAC latch. CS and WR control the loading of the input latch while LDAC ...
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... The CLR line can be used to ensure power- the AD7245A output in unipolar operation and is also use- ful, when used as a zero override, in system calibration cycles. Figure 4 shows the input control logic for the AD7245A and the write cycle timing for the part is shown in Figure 5. LDAC ...
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... No Data Transfer Operation H = High State Low State APPLYING THE AD7245A/AD7248A The internal scaling resistors provided on the AD7245A/ AD7248A allow several output voltage ranges. The part can produce unipolar output ranges and a bipolar output range of – Connections for the various ranges are outlined below ...
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... MOSFET transistor, the VN0300M, to 1 provide a programmable current sink from V × The VN0300M is placed in the feedback of the AD7245A/ 2048 AD7248A amplifier. The entire circuit can be operated in single 2047 supply by tying the V × ...
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... LOW. AD0–AD11 of the 16-bit data bus are connected to the AD7245A data bus (DB0–DB11). The 12-bit word is written to the AD7245A in one MOV instruction and the analog output responds immediately. In this example the DAC address is D000. A software routine for Figure 12 is given in Table V. ...
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... Figure 14. Once again the AD7245A is used in the single buffered mode. A software routine for load- ing data to the AD7245A is given in Table VI. In this example the AD7245A is located at address E000, and the 12-bit word is written to the DAC in one MOVE instruction. ...
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... AD7245A/AD7248A A connection diagram for the interface between the AD7248A and 68008 microprocessor is shown in Figure 16. Once again the AD7248A acts as a memory mapped device and data is right justified. In this case the AD7248A is configured in the auto- matic transfer mode which means that the high byte of the input latch has the same address as the DAC latch ...
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... REF 0.055 (1.40) 0.088 (2.24) 0.045 (1.14) 0.054 (1.37) NOTES 1 THIS DIMENSION CONTROLS THE OVERALL PACKAGE THICKNESS. 2 APPLIES TO ALL FOUR SIDES. ALL TERMINALS ARE GOLD PLATED MECHANICAL INFORMATION—AD7245A OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 24-Lead Plastic DIP (N-24) 1.228 (31.19) 1.126 (31.14 0.260 0.001 (6.61 0.03 ...
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... AD7245A/AD7248A 20-Lead Plastic DIP (N-20) 1.07 (27.18) MAX 20 11 0.255 (6.477) 0.245 (6.223 PIN 1 0.021 (0.533) 0.015 (0.381) 0.145 (3.683) 0.125 MIN (3.175) MIN 0.021 (0.533) 0.070 (1.77) 15 0.015 (0.381) 0.045 (1.15) LEAD NO. 1 IDENTIFIED BY DOT OR NOTCH. LEADS ARE SOLDER OR TIN-PLATED KOVAR OR ALLOY 42 20-Lead SOIC (R-20) 0 ...