MAX1233ETI+T Maxim Integrated Products, MAX1233ETI+T Datasheet
MAX1233ETI+T
Specifications of MAX1233ETI+T
Related parts for MAX1233ETI+T
MAX1233ETI+T Summary of contents
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... MAX1234EGI 17 R1 MAX1234ETI TransZorb is a trademark of General Semiconductor Industries, Inc. SPI and QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. AutoShutdown is a trademark of Maxim Integrated Products, Inc. Features ) DD ™ ™ /MICROWIRE -Compatible 10MHz ™ Between Conversions Ordering Information ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ABSOLUTE MAXIMUM RATINGS AV to GND............................................................-0. .......................................................-0.3V to +0. Digital Inputs/Outputs to GND .................-0.3V to (DV X+, Y+, X-, Y-, AUX1, AUX2, and ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ELECTRICAL CHARACTERISTICS (continued) ( +2.7V to +3.6V (MAX1233 (MAX1233 4.096V (MAX1234); f REF +85°C, unless otherwise noted. Typical values are at T PARAMETER ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ELECTRICAL CHARACTERISTICS (continued) ( +2.7V to +3.6V (MAX1233 (MAX1233 4.096V (MAX1234); f REF +85°C, unless otherwise noted. Typical values are at T PARAMETER ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ELECTRICAL CHARACTERISTICS (continued) ( +2.7V to +3.6V (MAX1233 (MAX1233 4.096V (MAX1234); f REF +85°C, unless otherwise noted. Typical values are at T PARAMETER ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ELECTRICAL CHARACTERISTICS (continued) ( +2.7V to +3.6V (MAX1233 (MAX1233 4.096V (MAX1234); f REF +85°C, unless otherwise noted. Typical values are at T Note ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ( (MAX1233 (MAX1234), external 10MHz (50% duty cycle 20ksps, C SAMPLE SHUTDOWN CURRENT vs. ANALOG SUPPLY VOLTAGE 300 250 200 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ( (MAX1233 (MAX1234), external 10MHz (50% duty cycle 20ksps, C SAMPLE ADC INTEGRAL NONLINEARITY vs. OUTPUT CODE 1.0 0.8 0.6 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ( (MAX1233 (MAX1234), external 10MHz (50% duty cycle 20ksps, C SAMPLE ADC EXTERNAL REFERENCE INPUT CURRENT vs. SAMPLING RATE 8 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ( (MAX1233 (MAX1234), external 10MHz (50% duty cycle 20ksps, C SAMPLE DAC FULL-SCALE ERROR vs. ANALOG SUPPLY VOLTAGE 0.75 0.50 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller ( (MAX1233 (MAX1234), external 10MHz (50% duty cycle 20ksps, C SAMPLE ADC REFERENCE SUPPLY CURRENT vs. ANALOG SUPPLY VOLTAGE 750 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller PIN NAME 19 C2 Keypad Column 2. Can be reconfigured as GPIO5 Keypad Column 3. Can be reconfigured as GPIO6 Keypad Column 4. Can be reconfigured as ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller MAX1233 MAX1234 *X+ *X- X/Y SWITCHES *Y+ *Y- *BAT1 BATTERY MONITOR *BAT2 BATTERY MONITOR *AUX1 *AUX2 REF 8-BIT DACOUT DAC *ESD PROTECTED Figure 1. Block Diagram +AV DD FORCE LINE Y+ ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller TEMP2 TEMP1 7.5kΩ V BAT1 7.5kΩ V BAT2 2.5kΩ BATTERY ON AUX1 AUX2 GND Figure 3. Simplified Diagram of Analog Input Section Analog Input Protection Internal protection ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller +1.25V BANDGAP Figure 4. Block Diagram of the Internal Reference measurement of the auxiliary inputs. Figure 4 shows the on-chip reference circuitry of the MAX1233/MAX1234. Set the internal ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller SW255 SW1 SW2 Figure 5. DAC Current-Steering Topology The DAC voltage output is an internally buffered unity- gain follower that slews ±0.4V/µs. The output can swing from zero ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller TO KEYPAD WAKEUP AND DEBOUNCE LOGIC Figure 7. Key-Press Detection Circuitry X+ PENIRQ BUSY CS DOUT Figure 8a. Timing Diagram for Touch-Initiated Screen Scan ______________________________________________________________________________________ SIMPLIFIED KEYPAD CIRCUITRY DRIVERS PULL HIGH ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller PENIRQ returns high only after a touch-screen scan is completed. PENIRQ does not go low again until one of the touch-screen data registers is read. Figures 8a and 8b show the ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Table 3. Register Summary WRITE READ REGISTER COMMAND COMMAND BIT15 BIT14 NAME (HEX) (HEX) — 0x8000 — 0x8001 — 0x8002 — 0x8003 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller In order to read the entire first page of memory, for example, the host processor must send the MAX1233/MAX1234 the command 0x8000 MAX1233/MAX1234 then begin clocking out 16-bit data starting with ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Bits 14-15: Pen Interrupt Status and These bits are used to control or monitor ADC scans. Bits 10-13: ADC Scan Select These bits control which input to convert and which con- ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Table 7. ADC Scan Select (Touch Screen, Battery, Auxiliary Channels, and Temperature) A/D3 A/D2 A/D1 A/D0 Configures the ADC reference as selected by RES [1:0] bits as shown in Table 13. ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Bits 1-3: Touch-Screen Settling Time Control These bits specify the time delay from pen-touch detec- tion to a conversion start. This allows the selection of the appropriate settling time for the ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Table 17. Keypad Control Register (Write 0x0041/Read 0x8041) BIT15 BIT14 BIT13 BIT12 KEYSTS1 KEYSTS0 DBN2 DBN1 Table 18. Keypad Control Register Bit Descriptions (Write 0x0041/Read 0x8041) BIT NAME 15 (MSB) KEYSTS1 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller allowing certain keys to be masked from detection. Tables 18–21 show the programmable bits of the keypad control register. Tables 23, 24, and 25 show the program- mable bits of the ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Table 25. Keypad Column Mask Register Bit Descriptions (Write 0x0051/Read 0x8051) BIT NAME 15 CM4 Mask interrupt, status register, and pending register data update on all keys in column 4 14 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Table 30. Analog Inputs Data Register Format READ REGISTER BIT15 BIT14 BIT13 BIT12 BIT11 BIT10 BIT9 COMMAND NAME 0x8000 0x8001 0x8002 0x8003 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Table 33. Keypad Data Register 1 (Pending Register) Descriptions BIT NAME 15 K1_15 Keypad scan result for row 4, column 4. Can only be masked by column mask. 14 K1_14 Keypad ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller The DAC data register stores data that written to the 8-bit DAC. Table 36 shows the configuration of the DAC data register right justified with bit ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller +AV DD FORCE LINE Y+ SENSE LINE +IN X+ -IN SENSE LINE FORCE LINE Y- GND Figure 12. Ratiometric Y-Coordinate Measurement ence power-up status when the A/D0–A/D3 bits are zero. These ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller FORCE LINE SENSE LINE X+ Y+ TOUCH V X-POSITION X- Y- OPEN CIRCUIT FORCE LINE SENSE LINE MEASURE Z1-RESISTANCE X+ TOUCH Z1-RESISTANCE X- FORCE LINE FORCE LINE OPEN CIRCUIT X+ Y+ ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Auxiliary Analog Inputs Two auxiliary analog inputs (AUX1 and AUX2) allow the MAX1233/MAX1234 to monitor analog input voltages from zero Figure 16 illustrates the process of REF auxiliary ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller HOST WRITES TEMPERATURE INPUT 1 ADC CONTROL REGISTER START CLOCK SET BUSY LOW IS ADC NO REFERENCE IN AUTO POWER-DOWN MODE? YES POWER UP REFERENCE POWER UP ADC CONVERT POWER DOWN ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Battery Voltage, Auxiliary Input, and Temperature Input Scan Use this scan to make periodic measurements of both battery inputs, both auxiliary inputs, and both tempera- ture inputs. The respective data registers ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller BATTERY VOLTAGE, AUXILIARY INPUT, AND TEMPERATURE INPUT SCAN ([A/D3:A/D0] = 1011) HOST WRITES ADC CONTROL REGISTER START CLOCK SET BUSY LOW IS ADC NO REFERENCE IN AUTO POWER-DOWN MODE? YES POWER ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller YES TURN ON DRIVERS: Y CONVERT X- COORDINATES NO STORE X- COORDINATES Figure 21. Touch-Initiated X- and Y- Coordinate Screen Scan 36 ______________________________________________________________________________________ PENIRQ-INITIATED X- AND Y- SCREEN SCAN ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller SCREEN TOUCH ARE THERE YES UNREAD SCAN RESULTS? NO SET PENIRQ LOW IS PENSTS BIT = 1? YES START CLOCK SET BUSY LOW TURN ON DRIVERS: Y TOUCH-SCREEN ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller YES NO NO Figure 23. Host-Initiated X- and Y- Coordinate Screen Scan 38 ______________________________________________________________________________________ HOST-INITIATED X- AND Y- SCREEN SCAN SCREEN TOUCH ARE THERE UNREAD SCAN RESULTS? NO SET PENIRQ LOW ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller SCREEN TOUCH ARE THERE YES UNREAD SCAN RESULTS? SET PENIRQ LOW IS PENSTS BIT = 1? HOST WRITES ADC CONTROL REGISTER START CLOCK SET BUSY LOW TURN ON DRIVERS: Y+, Y- ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller KEY-PRESS-INITIATED DEBOUNCE SCAN KEYPAD TOUCH ARE THERE YES UNREAD DEBOUNCE RESULTS? NO SET KEYIRQ LOW HOST-INITIATED IS KEYSTS1 = 1? YES START CLOCK SET BUSY LOW SCAN AND ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller MAX1233 MAX1234 FEEDBACK RESISTORS AV DD DACOUT R3 DAC i 3 Figure 27. LCD Contrast Control Circuit CS SCK MISO SPI V DD MOSI SS Figure 28a. SPI Interface Equation 5 ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller CS SCK MISO QSPI V MOSI DD SS Figure 29. QSPI Interface SUPPLIES +3V/+5V GND R* = 10Ω AV GND MAX1233 MAX1234 *OPTIONAL Figure 30. Power-Supply Grounding Connection ...
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ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller Signal-to-Noise Ratio For a waveform perfectly reconstructed from digital sam- ples, signal-to-noise ratio (SNR) is the ratio of full-scale analog input (RMS value) to the RMS quantization error (residual error). The ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 44 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2008 Maxim Integrated Products ...