AD7843ARUZ Analog Devices Inc, AD7843ARUZ Datasheet
AD7843ARUZ
Specifications of AD7843ARUZ
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AD7843ARUZ Summary of contents
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FEATURES 4-wire touch screen interface Specified throughput rate of 125 kSPS Low power consumption: 1.37 mW max at 125 kSPS with Single supply 2 5. Ratiometric conversion High speed ...
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AD7843 TABLE OF CONTENTS Specifications..................................................................................... 3 Timing Specifications .................................................................. 4 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Terminology ...................................................................................... 7 Typical Performance Characteristics ............................................. 8 Circuit Information ........................................................................ 11 ADC Transfer Function............................................................. 11 Typical ...
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SPECIFICATIONS MHz REF SCLK Table 1. Parameter DC ACCURACY Resolution No Missing Codes 2 Integral Nonlinearity 2 Offset Error 3 Offset Error Match 2 ...
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AD7843 Parameter POWER REQUIREMENTS V (Specified Performance Normal Mode (f = 125 kSPS) SAMPLE Normal Mode (f = 12.5 kSPS) SAMPLE Normal Mode (Static) Shutdown Mode (Static) 5 Power Dissipation Normal Mode (f = 125 kSPS) ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter +V to GND CC Analog Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND V to GND REF Input Current to Any ...
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AD7843 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Function Power Supply Input. The +V CC directly together Position Input. ADC Input Channel Position Input. ...
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TERMINOLOGY Integral Nonlinearity This is the maximum deviation from a straight line passing through the endpoints of the ADC transfer function. The endpoints of the transfer function are zero scale, a point 1 LSB below the first code transition, and ...
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AD7843 TYPICAL PERFORMANCE CHARACTERISTICS 207 206 205 204 203 202 201 200 199 198 –40 – TEMPERATURE (°C) Figure 4. Supply Current vs. Temperature 230 f 220 SAMPLE REF 210 200 190 180 170 ...
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SAMPLE RATE (kHz) Figure 10. Reference Current vs. Sample Rate X– 6 Y– 2.0 2.5 3.0 3.5 ...
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AD7843 3V 2.5V CC REF 100mV p-p SINEWAVE – 125kHz, = 20kHz SAMPLE IN –40 –60 –80 –100 –120 RIPPLE FREQUENCY ...
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CIRCUIT INFORMATION The AD7843 is a fast, low-power, 12-bit, single-supply, A/D converter. The AD7843 can be operated from a 2 5.25 V supply. When operated from either supply supply, the AD7843 ...
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AD7843 ANALOG INPUT Figure 19 shows an equivalent circuit of the analog input structure of the AD7843, which contains a block diagram of the input multiplexer, the differential input of the ADC, and the differential reference. Table 5 shows the ...
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Touch Screen Settling In some applications, external capacitors could be required across the touch screen to filter noise associated with it, for example, noise generated by the LCD panel or backlight circuitry. The value of these capacitors causes a settling ...
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AD7843 CONTROL REGISTER The control word provided to the ADC via the DIN pin is shown in Table 6. This provides the conversion start, channel addressing, ADC conversion resolution, configuration, and power-down of the AD7843. Table 6 provides detailed information ...
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POWER VS. THROUGHPUT RATE By using the power-down options on the AD7843 when not converting, the average power consumption of the device decreases at lower throughput rates. Figure 23 shows how, as the throughput rate is reduced while maintaining the ...
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AD7843 SERIAL INTERFACE Figure 24 shows the typical operation of the serial interface of the AD7843. The serial clock provides the conversion clock and also controls the transfer of information to and from the AD7843. One complete conversion can be ...
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DETAILED SERIAL INTERFACE TIMING Figure 25 shows the detailed timing diagram for serial interfacing to the AD7843. Writing information to the control register takes place on the first eight rising edges of DCLK in a data transfer. The control register ...
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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 26. This timing diagram also allows for the ...
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PEN INTERRUPT REQUEST The pen interrupt equivalent output circuitry is outlined in Figure 28. By connecting a pull-up resistor (10 kΩ to 100 kΩ) between V and this CMOS logic open-drain output, the CC PENIRQ output remains high normally. If ...
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AD7843 OUTLINE DIMENSIONS 0.193 BSC 9 16 0.154 BSC 0.236 1 BSC 8 PIN 1 0.069 0.065 0.053 0.049 0.010 0.025 0.012 0.004 SEATING BSC 0.008 PLANE COPLANARITY 0.004 COMPLIANT TO JEDEC STANDARDS MO-137AB Figure 30. 16-Lead Shrink Small Outline ...