ak4181a AKM Semiconductor, Inc., ak4181a Datasheet
ak4181a
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ak4181a Summary of contents
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... PENIRQN PEN INTERRUPT MS0313-E-00 General Description: The AK4181A is a 4-wire touch screen controller that incorporates a 12-bit 125kHz sampling SAR A/D converter. The AK4181A can detect the pressed screen location by performing two A/D conversions. In addition to location, the AK4181A also measures touch screen pressure. On-chip VREF can be utilized for two analog auxiliary inputs and battery monitoring, with the ability to measure voltages from ...
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... ASAHI KASEI Ordering Guide -20°C ∼ +70°C AK4181AVT Pin Layout VCC GND 6 VBAT 7 IN1 8 MS0313-E-00 16pinTSSOP 16 DCLK 15 CSN 14 DIN 13 BUSY Top View 12 DOUT 11 PENIRQN 10 IN2 9 VREF 2 [AK4181A] 2004/06 ...
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... DIN I Serial Data Input Inputs 8-bit control command data serially when CSN= “L” AK4181A latches at the rising edge of DCLK. Must keep “L” while not issuing commands. 15 CSN I Chip Select Input Enables writing data to the registers when CSN= “L”. ...
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... Note 1. All voltages with respect to ground. WARNING: AKM assumes no responsibility for the usage beyond the conditions in this datasheet. MS0313-E-00 Absolute Maximum Ratings Symbol Min VCC -0.3 IIN - VIN -0.3 IOUTDRV Ta -20 Tstg -65 Symbol Min VCC 2.7 4 [AK4181A] max Units 6.0 V ±10 mA 6.0(VCC+0. °C 70 °C 150 typ max Units 3.3 3.6 V 2004/06 ...
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... Note 3. “ideal” value derived from theory Note 4. Accuracy is defined as the difference between the voltage measured by two current sources, and the ideal voltage derived from theory at specific temperatures. MS0313-E-00 Analog Characteristics min 11 0 2.45 0.1 5 -20 5 [AK4181A] typ max Units 12 Bits 12 Bits ±2 LSB ±1 LSB Vref V ± ...
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... PD0 D11 Figure 1 AK4181A Timing Diagram 6 [AK4181A] typ max Units - V - 0.2xVCC V µ 0.4 V µA 10 µA 50 0.8 V typ max Units 125 kHz 2100 kHz µ ...
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... The SAR A/D converter output is a straight binary format as shown below: (∆VREF-1.5LSB)~ ∆VREF (∆VREF-2.5LSB) ~ (∆VREF-1.5LSB) The full scale (∆VREF) of the A/D converter depends on the input mode. The AK4181A is controlled by the 8 bit serial command on DIN. Analog Inputs Analog input is selected via the A2, A1, A0 and SER/ DFR bits in the control register. If the analog inputs are selected to the X or Y-axis, SER/ DFR = “ ...
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... X-position, Y-Position, and Z1-Position, and then using the following formula: Rtouch = (Rxplate*Xposition/4096)*[(4096/Z1) – 1] – Ryplate*[1 – (Yposition/4096)] MS0313-E-00 XP VREF YP ADC VREF Y-Position Measurement Differential Mode Figure 2 Axis Measurement 8 [AK4181A AIN+ YP AIN 2004/06 ...
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... Z1-Position Measurement Differential Mode Voltage Reference The AK4181A has an internal 2.5V voltage reference. This reference can be turned ON when PD1 = “1”, and OFF when PD1 = “0”. This reference is used in the single-ended mode for the battery monitoring, temperature measurement, or for auxiliary input. ...
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... The diode characteristic is approximately shown as a diode junction voltage. That is theoretically proportional to the temperature; the ambient temperature can be predicted by knowing this voltage. As the AK4181A has two different fixed current circuits and a diode (temperature sensor), the temperature can be measured by using two different methods. ...
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... ASAHI KASEI Control Command The control command, 8 bits, provided to the AK4181A via DIN is shown in the following table. This command includes start bit, channel selection, resolution, measurement configuration, and power-down mode. The AK4181A latches the serial command at the rising edge of DCLK. Table 2 gives detailed information regarding the bit order, function, the status of driver switch, ADC input, reference voltage ...
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... A/D converter is automatically powered up at the start of the conversion, and goes to power- down state automatically at the end of the conversion. And the AK4181A is always powered down at this mode if CSN= “H”. All touch screen driver switches except for YN switch are turned off and relative pins are open state ...
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... The AK4181A outputs A/D data with MSB first via DOUT from the falling edge of 9th DCLK. DIN must keep low state for minimum 7 DCLK times (9th-15th DCLK) after command is sent on the DIN. The AK4181A can output one A/D data per 15 DCLK clock cycles for the fastest way as shown in the dotted line of the Figure 6. Pen Interrupt The AK4181A has pen interrupt function to detect the pen touch ...
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... The sequence is that 1) Power On with CSN = “L” or “H” then CSN = “H”. 2) Send control command after CSN = “L”. 3) CSN = “H” again. Once sending command to fix the internal register after first power up, the state of AK4181A is held on the condition of state as last command issued ...
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... ASAHI KASEI 16pin TSSOP (Unit: mm) 5.00±0. 0.22±0.08 | 0.13|M Seating Plane | 0.10 Package & Lead frame material Package molding compound: Epoxy Lead frame material: Cu Lead frame surface treatment: Solder (Pb free) plate MS0313-E-00 Package 0.65 0.17±0.05 Detail A 15 [AK4181A] 0.07±0.04 0-10° 2004/06 ...
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... ASAHI KASEI MS0313-E-00 Marking AKM 4181AVT XXYYY Contents of XXYYY XX: Lot # YYY: Date Code 16 [AK4181A] 2004/06 ...
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... AKM harmless from any and all claims arising from the use of said product in the absence of such notification. MS0313-E-00 IMPORTANT NOTICE 17 [AK4181A] 2004/06 ...