ak4184a AKM Semiconductor, Inc., ak4184a Datasheet
ak4184a
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ak4184a Summary of contents
Page 1
... GPIO ports, and a PWM generator for LED contrast control. The AK4184A operates down to a 2.5V supply voltage, and it tolerates digital I/O interface voltage from 1.6V to AVDD in order to connect to low voltage controllers. The AK4184A supports SPI interface for communication to a host controller. The AK4184A is available in a 41-pin BGA package and it operates over a temperature range of -40° ...
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... Keypad Scanner VREF+ VREF- AIN+ 12bit ADC AIN- (SAR type OSCILLATOR Figure 1. Block Diagram - 2 - [AK4184A] GP0 GP1 GP2 GP3 GP4 GP5 GPIO I/F GP6 GP7 IOVDD Control SCLK Logic CSN DOUT Serial DIN Data ...
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... Ordering Guide AK4184AEG −40 ∼ +85°C AKD4184A ■ Pin Layout (BGA 41pin VSS2 2 IOVDD MS0947-E-00 AK4184A Evaluation board AK4184AEG Top View BRCONT C4 C6 GP0 VSS2 R1 BUSY DIN ...
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... PIN/FUNCTION No internal bonding. This pin should be open or connected to the ground. This pin is “L” key press (when the AK4184A is allowed to detect a key press). This pin is “H” after a debounce scan is completed. This is always “H” when the device is in key interrupt disable state. ...
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... R3 I Keypad Row Keypad Row 2 A3 VSS2 - Digital I/O Ground Keypad Row 1 A2 IOVDD - Digital I/O Power Supply: 1.6V ~ AVDD MS0947-E-00 No internal bonding. This pin should be open or connected to the ground. No internal bonding. This pin should be open or connected to the ground [AK4184A] 2008/04 ...
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... These pins should be open. ABSOLUTE MAXIMUM RATINGS Symbol AVDD IOVDD IIN VINA VIND IOUTDRV Ta Tstg RECOMMEND OPERATING CONDITIONS Symbol AVDD IOVDD - 6 - min max -0.3 6.0 -0.3 6.0 ±10 - -0.3 AVDD+0.3 or 6.0 -0.3 IOVDD+0 -40 85 -65 150 min typ max 2.5 3.3 3.6 1.6 3.3 AVDD [AK4184A] Units °C °C Units V V 2008/04 ...
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Ta = -40°C to 85°C, AVDD = IOVDD = 3.3V 125 KHz, fSCLK=5MHz Parameter ADC for Touch Screen Resolution No Missing Codes Integral Nonlinearity (INL) Error Differential Nonlinearity (DNL) Error Offset Error Gain Error Touch Panel Drivers Switch ...
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... Figure 2. Timing Diagram tRST Figure 3. Power-down & Reset Timing - 8 - [AK4184A] typ max 1.3 1.7 - 1000 - - - 125 - - - - - - - - - tCSW tCSH tDD tCDZ D11 ...
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... Touch Screen A/D Converter The AK4184A incorporates a 12-bit successive approximation resistor (SAR) A/D converter for determining the touch position and pressure measurement. The architecture is based on a capacitive redistribution algorithm, and an internal capacitor array functions as the sample/hold (S/H) circuit. The SAR A/D converter output is in straight binary format as shown below: (Δ ...
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... XN X-Plate XP Y-Plate VREF+ YP ADC VREF YN-Driver Y-Position Measurement Differential Mode 4-wire Touch Screen Figure 4. Axis Measurement - 10 - AVDD X-Plate YP-Driver Y-Plate AIN+ YP AIN- XN Touch Screen YN X-Plate (Top side) Y-Plate (Bottom side) [AK4184A] 2008/04 ...
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... Rtouch = (Rxplate * Xposition/4096) * [(4096/Z1) – 1] – Ryplate * [1 – (Yposition/4096)] AVDD YP-Driver SW ON VREF+ AIN+ ADC VREF- AIN- XN-Driver Z1-Position Measurement MS0947-E-00 YP-Driver Rtouch VREF+ ADC VREF- XN XN-Driver Figure 5. Pen Pressure Measurements - 11 - AVDD YP XP AIN+ AIN Z2-Position Measurement [AK4184A] Rtouch 2008/04 ...
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... Keypad Interrupt Detection When the AK4184A is in key interrupt enabled mode pins are designed to output “H” and pins are designed to pull to GND via Rkey (Rkey=16kΩ typ, and the KEYIRQN pin goes “L”. The KEYIRQN pin returns “H” after key press scan is completed. The KEYIRQN pin does not go “ ...
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... R key key key Debounce Scan Key pressed Key debounce time interval Oscillator startup Figure 7. Debounce Time Interval - 13 - [AK4184A Store the Key value in the KPDATA1, the KPDATA2 Register ...
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... Digital Interface The AK4184A supports a SPI bus system. The Host processor starts to communicate with the serial clock. The digital interface can be operated from 1.6V, which enables connecting with a low voltage host controller. The full scale level of the digital I/O voltage is specified IOVDD. ...
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... PU3 PU2 PU1 PU0 PS5 PS4 PS3 PS2 PS1 PS0 BRV[4] BRV[3] BRV[2] BRV[1] BRV[ Table 4. AK4184A Register Map - ADDR[5: KD2[2] KD2[1] KD2[0] KD1[4] KD1[3] KS2[2] KS2[1] KS2[0] KS1[4] KS1[3] 0 ...
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... System Reset Upon power-up, all blocks of the AK4184A must be reset by the RESETN pin = “L”. This ensures that all internal registers are reset to their initial values (0000H). The touch screen control data is set to X-measurement and auto driver off (A1 bit=A0 bit = PD bit=“0”). Internal state is fixed and the pen interrupt function is enabled. If the AVDD and IOVDD are supplied separately, the power up sequence is not critical. ■ ...
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... When PD bit is “0”, the touch screen driver switches and the A/D converter are automatically powered up at the start of sampling, and moves to power- down state automatically at the rising edge of CSN. The AK4184A is always powered down when CSN is “H”. All touch screen driver switches except for the YN switch are turned off, and relative pins are in open state ...
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... SCLK, DIN, and DOUT pins). BUSY and DOUT are in Hi-Z state when CSN = “H”. The AK4184A latches the 4-bit control word serially via DIN on the rising edge of SCLK. DIN must be low until CSN is “H”. The S bit must be “1”. ...
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... Pen Interrupt The AK4184A has a pen interrupt function to detect a pen touch. The pen interrupt function is enabled during power- down state. The YN pin is connected to GND during the pen interrupt enabled state. The XP pin is pulled up via an internal resistor (Ri), typically 50kΩ. If the touch plate is pressed by a pen, the current flows via <AVDD> - <Ri> - < ...
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... Figure 12. Read Operation - 20 - Table 12, Table 13. The upper MSB byte Table ADDR[5: Control Data Read Data [AK4184A] Table for the Hi-Z 32 Hi-Z 0 2008/04 ...
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... The keypad data register (KPDATA1, KPDATA2) is revised after completing a debounce scan. The KEYIQRN pin goes to “H” and the AK4184A goes to hold state. Key press detect function is disabled during the hold time. When the host processor reads the keypad data register during hold time, the hold time counter is reset and restarted after being read by the host processor ...
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... Keypad Debounce scan is busy Wait for the command initiated by Host detect 1 1 Data available Table 13. KST bit (Read Debounce HOLD Scan Key Detect Enable then wait (Table 12), Keypad Mask register [AK4184A] (Table LSB 2008/04 ...
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... D12 D11 D10 D9 D8 KM13 KM12 KM11 KM10 KM9 KM28 KM27 KM26 KM25 KM24 Table 16. Keypad Mark Register Format Description Table 17. Keypad Mask bit - 23 - [AK4184A] Function Function KM8 KM7 KM6 KM5 KM4 KM23 KM22 KM21 KM20 KM19 Table 24. KPMASK1, ...
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... Keypad Scan Initiate Command (PAGE 1) When a key is pressed with the KST0 bit = “1”, the AK4184A does not start debounce and key scan, the Host Controller sends a keypad scan initiate command to the AK4184A. After receiving the command, the AK4184A starts a debounce scan, and the Host Controller can then read the data [D15:D0] from the keypad data register (KPDATA1, KPDATA2) ...
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... Data of KD1, KD2, KD3, KS1, KS2 and KS3 returned as zero represents no key pressed. The AK4184A keypad scanner can be read out up to three keys simultaneously. The AK4184A key pad scanner writes the number of keys pressed in the keypad data register. For example: When two keys are pressed at the same time, the contents of the keypad register are filled with KD1, KD2, KS1, and KS2 ...
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... GPIO controller The AK4184A has eight ports [GP0:GP7] which can be configured as inputs or outputs for general purpose. shows a block diagram of a single GPIO pin. The GPIO Pin Direction register (GPDR) is used to program the GPIO pins as input or output. For a pin configured as output, use the GPIO pin pull-up register (GPPU) to set the pin type to either Open-Drain or CMOS, and use the GPIO Set/ Clear register (GPSCR) to set a pin level high or low ...
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... Table 33. GPIO Pin Level Register Format Description Table 34. GPIO Pin Level Register - PS0 GPD6 GPD5 GPD4 GPD3 GPD2 [AK4184A GPD1 GPD0 2008/04 ...
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... LED contrast control The AK4184A contains an oscillator and a PWM control circuit for controlling the brightness of an LED by modulating the “on” time. The brightness is determined by the PWM basic frequency (f PWM block divides the internal oscillator frequency (fosc) and modulates this output. The range of PWM frequency (fpwm) is 80Hz minimum ...
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... TPPD Enable the touch screen control block power up/down 0: power up (default) 1: power down MS0947-E-00 D12 D11 D10 Table 37. Power Down Register Format Table 38. Power Down Register - 29 - [AK4184A KPPD 2008/04 D0 TPPD ...
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... When an EMI source is close to the touch panel analog signal line, EMI noise reduces analog performance characteristics. Noise canceling capacitors as close as possible to each pin (XP, XN, YP, YN pins) of the AK4184A should be connected to avoid this noise. printed circuit board for countermeasure for surge and static electricity on the touch panel, GPIO and keypad signal lines ...
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... X-, Y- Coordinate measurements CSN X, 0 pin Figure 19. Timing Sequence for detecting X, Y position MS0947-E-00 CONTROL SEQUENCE Cycle repeat repeat X-measurement, Y: Y-measurement bit = “0” setting bit = “1” setting [AK4184A 2008/04 ...
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... Figure 20. Keypad scanner sequence initiated by Host command MS0947-E-00 Keypad Touch Read No KPDATA1,2 Register? Yes KEYIRQN pin Low Write KPScanInitiate Register Start Clock BUSY pin High Start Scanning & Debouncing keys Store scan results in KPDATA1, 2 Register BUSY pin Low Stop Clock KEYIRQN pin High Done - 32 - [AK4184A] 2008/04 ...
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... Figure 21. Keypad scanner sequence initiated by key press MS0947-E-00 Keypad Touch Read No KPDATA1,2 Register? Yes KEYIRQN pin Low Start Clock BUSY pin High Start Scanning & Debouncing keys Store scan results in KPDATA1, 2 Register BUSY pin Low Stop Clock KEYIRQN pin High Done - 33 - [AK4184A] 2008/04 ...
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... FBGA (Unit: mm) 4.0 ± 0.1 ■ Material & Lead finish Package molding compound: Interposer material: Solder ball material: MS0947-E-00 PACKAGE 41 - φ 0.3 ± 0.05 φ 0. 0.08 S Epoxy BT resin SnAgCu - 34 - [AK4184A 0.5 0.5 3.0 2008/04 ...
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... Date (YY/MM/DD) Revision 08/04/16 00 MS0947-E-00 MARKING 4184A XXXX XXXX: Date code identifier (4 digits) Pin #A1 indication REVISION HISTORY Reason Page Contents First Edition - 35 - [AK4184A] 2008/04 ...
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... AKEMD harmless from any and all claims arising from the use of said product in the absence of such notification. MS0947-E-00 IMPORTANT NOTICE , and AKEMD assumes no responsibility for such use, except Note2 [AK4184A] in any safety, life Note1) 2008/04 ...