MXB7846EEE MAXIM [Maxim Integrated Products], MXB7846EEE Datasheet
MXB7846EEE
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MXB7846EEE Summary of contents
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... Auxiliary Analog Input Automatic Shutdown Between Conversions Low Power (External Reference) 270µA at 125ksps 115µA at 50ksps 25µA at 10ksps 5µA at 1ksps 2µA Shutdown Current Applications PART MXB7846EEE MXB7846EUE TOP VIEW Features Ordering Information TEMP RANGE PIN-PACKAGE - + QSOP - +85 C ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor ABSOLUTE MAXIMUM RATINGS , VBAT, DIN, CS, DCLK to GND ........................-0. Digital Outputs to GND...............................-0. X+, X-, Y+, Y-, AUX ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor ELECTRICAL CHARACTERISTICS (continued 2.7V to 3.6V 2.5V REF DCLK unless otherwise noted. Typical values are at T MIN ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor TIMING CHARACTERISTICS (Figure 2.7V to 3.6V 2.5V REF DCLK unless otherwise noted. Typical values are at T ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor (V = 2.7V 2. REF EXTERNAL DCLK otherwise noted.) INTEGRAL NONLINEARITY vs. DIGITAL OUTPUT CODE 0.5 0.4 0.3 0.2 0.1 0 -0.1 -0.2 ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor (V = 2.7V 2. REF EXTERNAL DCLK otherwise noted.) INTERNAL REFERENCE VOLTAGE vs. TEMPERATURE 2.6 2.5 2.4 2.3 2.2 2 2.7V ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor (V = 2.7V 2. REF EXTERNAL DCLK otherwise noted.) SUPPLY CURRENT vs. SUPPLY VOLTAGE 250 f = 12.5kHz SAMPLE 225 200 175 150 ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor PIN NAME 1 V Positive Supply Voltage. Connect to pin 10 Position Input, ADC Input Channel Position Input, ADC Input ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor Detailed Description The MXB7846 uses a successive-approximation conver- sion technique to convert analog signals to a 12-bit digi- tal output. An SPI/QSPI/MICROWIRE™-compatible serial interface provides easy communication to ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor BAT AUX REF Table 1. Input Configuration, Single-Ended Reference Mode (SER/DFR HIGH MEASUREMENT position ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor Input Bandwidth and Anti-Aliasing The ADCs input tracking circuitry has a 25MHz small- signal bandwidth possible to digitize high- speed transient events. To avoid high-frequency ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor +IN X+ -IN Y- GND Figure 3. Single-Ended Y-Coordinate Measurement TOUCH SCREEN Figure 5. PENIRQ Functional Block Diagram 12 ______________________________________________________________________________________ REF REF+ 12-BIT ADC REF- ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor SCREEN TOUCHED HERE PENIRQ CS DCLK DIN INTERRUPT PROCESSOR t TOUCH Figure 6. PENIRQ Timing Diagram TOUCH ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor ward bias voltage is measured by the ADC with an address and known tem- perature. Subsequent ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor Table 3. Control Byte Format BIT 7 BIT 6 BIT 5 START A2 A1 BIT NAME 7 START Start bit 6 A2 Address (Tables 1 and 2) 5 ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor Table 4. Power-Mode Selection PENIRQ PD1 PD0 0 0 Enabled ADC is ON during conversion, OFF between conversion 0 1 Disabled ADC is always ON, reference is always ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor The MXB7846 output data is in straight binary format as shown in Figure 12. This figure shows the ideal output code for the given input voltage and does ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor the MXB7846 to initiate a conversion, the MXB7846 biases the touch screen through the internal switches at the beginning of the acquisition period. The voltage transient at the ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor Hardware Power-Down CS also places the MXB7846 into power-down. When CS goes HIGH, the MXB7846 immediately powers down and aborts the current conversion. The internal reference does not ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor CS DCLK DIN START BUSY DOUT Figure 16. MXB7846-to-TMS320 Serial Interface Timing Diagram 2) The MXB7846’s CS pin is driven low by the TMS320’s XF ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor Differential Nonlinearity Differential nonlinearity (DNL) is the difference between an actual step width and the ideal value of 1LSB. A DNL error specification of less than 1LSB guarantees ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 22 ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, QSOP .150", .025" LEAD PITCH ...
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Touch-Screen Controller with Internal Reference and Temperature Sensor (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) Maxim cannot assume responsibility for ...