EVAL-AD7843CB3 AD [Analog Devices], EVAL-AD7843CB3 Datasheet
EVAL-AD7843CB3
Related parts for EVAL-AD7843CB3
EVAL-AD7843CB3 Summary of contents
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GENERAL DESCRIPTION The AD7843 is a 12-bit successive-approximation ADC with a synchronous serial interface and low on resistance switches for driving touch screens. The part operates from a single 2 5.25 V power supply and features throughput ...
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AD7843–SPECIFICATIONS Parameter DC ACCURACY Resolution No Missing Codes 2 Integral Nonlinearity 2 Offset Error 3 Offset Error Match 2 Gain Error 3 Gain Error Match Power Supply Rejection SWITCH DRIVERS 2 On-Resistance Y+, X+ Y–, X– ANALOG INPUT Input Voltage ...
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TIMING SPECIFICATIONS Parameter Limit MIN DCLK 2 t 1.5 ACQ 200 4 t 200 ...
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... This can be used as a stand-alone evaluation board or in conjunction with the EVALUATION BOARD CONTROLLER for evaluation/demonstration purposes. 4 This EVALUATION BOARD CONTROLLER is a complete unit allowing control and communicate with all Analog Devices evaluation boards ending in the CB designators. 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 ...
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Pin No. Mnemonic Function Power Supply Input. The + connected directly together Position Input. ADC Input Channel Position Input. ADC Input Channel 2. 4 X– X– Position Input. ...
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AD7843–Typical Performance Characteristics 207 206 205 204 203 202 201 200 199 198 –40 – TEMPERATURE – C 230 220 210 200 190 180 170 160 150 2.2 2.6 3.0 3.4 3.8 +V – 0.20 ...
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SAMPLE RATE – kHz X– 6 Y– 2.0 2.5 3.0 3.5 4.0 4.5 +V –V CC 2.0 ...
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AD7843 TPC 12 shows a typical FFT plot for the auxiliary channels of the AD7843 at 125 kHz sample rate and 15 kHz input frequency. TPC 13 shows the power supply rejection ratio versus V supply frequency for the AD7843. ...
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ANALOG INPUT Figure 4 shows an equivalent circuit of the analog input struc- ture of the AD7843 which contains a block diagram of the input multiplexer, the differential input of the A/D converter and the differential reference. Table I shows ...
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AD7843 Table I. Analog Input, Reference, and Touch Screen Control SER/DFR ...
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V The disadvantage of this mode of operation is that during both the acquisition phase and conversion process, the external touch screen must remain powered. ...
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AD7843 PENIRQ PD1 PD0 Description 0 0 Enabled This configuration will result in power-down of the device between conversions. The AD7843 will only power down between conversions. Once PD1 and PD0 have been set the conversion will ...
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CS 1 DCLK DIN (START) IDLE THREE-STATE BUSY THREE-STATE DOUT X/Y SWITCHES (1) OFF (SER/DFR HIGH) OFF X/Y SWITCHES (1,2) (SER/DFR LOW) NOTES 1 Y DRIVERS ARE ON WHEN X IS SELECTED INPUT CHANNEL (A2–A0 = ...
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AD7843 Sixteen Clocks per Cycle The control bits for the next conversion can be overlapped with the current conversion to allow for a conversion every 16 DCLK cycles, as shown in Figure 11. This timing diagram also allows for the ...
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Table III), when the touch screen connected to the AD7843 is touched via a pen or finger, the PENIRQ output will go low initiating an interrupt to a microprocessor which may then instruct a control word to ...
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AD7843 16-Lead QSOP (RQ-16) 0.197 (5.00) 0.189 (4.80 0.244 (6.20) 0.157 (3.99) 0.150 (3.81) 0.228 (5.79 PIN 1 0.069 (1.75) 0.059 (1.50) 0.053 (1.35) MAX 0.010 (0.25) 0.025 0.012 (0.30) SEATING 0.010 (0.20) (0.64) 0.008 (0.20) ...