ak4180 AKM Semiconductor, Inc., ak4180 Datasheet
ak4180
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ak4180 Summary of contents
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... IRQN IN TERRUPT <MS0195-E-01> Touch Screen Controller General Description: The AK4180 is a 4-wire touch screen controller that incorporates a 12-bit 125kHz sampling SAR A/D converter. The AK4180 can detect the pressed screen location by performing two A/D conversions. In addition to location, the AK4180 also measures touchscreen pressure. ...
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... KASEI] T Ordering Guide AK4180VT - Pin Layout VCC GND 6 VBAT 7 IN1 8 <MS0195-E-01> 16pinTSSOP 16 DCLK 15 CSN 14 DIN 13 BUSY 12 DOUT NIRQN 10 IN2 9 VREF 2 [AK4180] 2003/02 ...
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... DIN I Serial Data Input Inputs 8-bit control command data serially when CSN=”L” AK4180 latches at the rising edge of DCLK. Please keep “L” except when issuing commands. 15 CSN I Chip Select Input Enables writing to the registers when CSN=”L”. CSN=”H” and DIN=”H” force the internal registers to initial value, 00h ...
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... Normal operation is not guaranteed at these extremes. GND=0V Parameter Power Supplies All voltages with respect to ground. <MS0195-E-01> Absolute Maximum Ratings Symbol Min VCC -0.3 IIN - VIN -0.3 IOUTDRV Ta -20 Tstg -65 Recommended Operating Conditions Symbol min VCC 2.7 4 [AK4180] max Units 6 6.0(VCC+0. 150 C typ max Units 3.3 3.6 V 2003/02 ...
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... Accuracy is defined as the difference between the voltage measured by two current sources, and the ideal voltage derived from theory at specific temperatures. <MS0195-E-01> Analog Characteristics min typ - 2.4 2.5 0.1 98 196 10 -20 1.6 250 520 0 5 [AK4180] Max Units Bits Bits LSB 5 Vref V 20 LSB 0 LSB dB 2. VCC ...
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... Symbol min fDCLK 10 duty 40 tTRK 1.5 tCONV t1 100 200 t5 200 t6 t7 100 t10 0 t11 t12 D11 AK4180 Timing Diagram 6 [AK4180] Typ max Units - V - 0.2xVCC 0 0.8 V Typ max Units 125 kHz 2000 kHz ...
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... KASEI] T A/D Converter for Touch Screen The AK4180 incorporates a12-bit successive approximation resistor A/D converter for position measurement, temperature, and battery voltage. The architecture is based on capacitive redistribution algorithm, and an internal capacitor array functions as the sample/hold circuit. The A/D converter output is a straight binary format as shown below: ( VREF-1 ...
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... The second method uses the resistances of both the X-plate and Y-plate. The resistance, Rtouch, is calculated from the results of three conversions, X-position, Y-Position, and Z1-Position, using the following formula: Rtouch = (Rxplate*Xposition/4096)*[(4096/Z1) – 1] – Ryplate*[1 – (Yposition/4096)] <MS0195-E-01> XP VREF+ YP ADC ADC ADC ADC VREF Y-Position Measurement Differential Mode Figure 1 Axis Measurement 8 [AK4180 AIN + YP AIN - 2003/02 ...
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... Differential Mode T Voltage Reference The AK4180 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 larger capacitor should be connected for stable operation of the VREF circuit. Setting time depends on this external capacitance, but 400 s or longer time is required if the external capacitance is 0 external voltage reference is used, PD1 bit should be set to “ ...
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... The diode characteristics is approximately showed As a diode junction voltage is theoretically proportional to the temperature, the ambient temperature can be predicted by knowing this voltage. As the AK4180 has two different fixed current circuits and a diode, the temperature can be measured by using two different methods. The first method needs two conversions, but can derive the temperature directly without knowing the voltage at a specific temperature. From equation < ...
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... KASEI] T Control Command The control command, 8 bits, provided to the AK4180 via DIN is shown in the following table. This command includes start bit, analog input, resolution, measurement configuration, and power-down mode. The AK4180 latches the serial command at the rising edge of DCLK ...
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... A/D converter is automatically powered up at the initiation of the conversion, and goes to power- down state automatically at the end of the conversion. And the AK4180 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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... BUSY is “H” for one DCLK period, which is from 8DCLK to 9DCLK . BUSY is “L” for other period. The AK4180 outputs A/D data with MSB first via DOUT from the falling edge of 9 The AK4180 can output one A/D data per 16 DCLK clock cycles for the fastest way as shown in the dotted line of the above figure. T Pen Interrupt The AK4180 has pen interrupt function to detect the pen touch ...
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... PD0)); /* CSN=”H”, (PD0, PD1) is not (1,1) */ <MS0195-E-01> EN2 20k Driver OFF Driver SER/ PD1 PD0 DFR [AK4180] 100k PENIRQN 2003/02 ...
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... KASEI] 16pin TSSOP (Unit: mm) 5.00TYP 16 1 0.22 0.08 | 0.13|M Seating Plane | 0.10 <MS0195-E-01> Package 0.65 0.17 0.05 Detail A 15 [AK4180] 1.10 MAX 0.07 0.04 0-10 2003/02 ...
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... KASEI] <MS0195-E-01> Marking AKM 4180VT XXYYY Contents of XXYYY XX: Lot # YYY: Date Code 16 [AK4180] 2003/02 ...
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... AKM harmless from any and all claims arising from the use of said product in the absence of such notification. <MS0195-E-01> IMPORTANT NOTICE 17 [AK4180] 2003/02 ...