ak4184a AKM Semiconductor, Inc., ak4184a Datasheet - Page 16

• Manufacturer Part Number: ak4184a
• Description: Tsc With Keypad Scanner And Gpio Expander
• Manufacturer: AKM Semiconductor, Inc.

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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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The control command (4 bits) provided to the AK4184A via DIN is shown in
bit, channel selection of ADC input, power-down mode of ADC and the next 12bits (written by “0” data). The
AK4184A latches the serial command on the rising edge of SCLK. Detail information regarding the bit order,
function, status of the driver switch, ADC input and reference voltage are shown in
MS0947-E-00
System Reset
Touch Screen Control Command
14:13
D15
11:0
Bits
S
15
12
S
1
1
1
1
D14
A1
A1
0
0
1
1
A1-A0
Input
Name
PD
S
A0
D13
0
1
0
1
A0
OFF OFF
OFF
OFF
Start Bit. This bit must be “1”
Channel Selection Bits. Analog inputs to the A/D converter and the activated driver
switches are selected. (
Power-down Mode
Reserved
Status of Driver Switch
ON
XP
D12
PD
XN
ON
ON
ON
Table 6. The definition of touch screen control data
Table 5. Touch Screen Command Word Format
D11
0
OFF OFF
ON
ON
ON
YP
Table 7. Status of Driver Switch
D10
0
(Table
OFF
OFF YN(Z2)
YN
ON
Table 7
D9
8)
0
XP(Z1)
AIN+
- 16 -
)
ADC input
YP
XP
(ΔAIN)
D8
0
AIN-
D7
XN
YN
XN
XN
Function
0
D6
0
Reference Voltage
VREF+
XP
YP
YP
YP
Table 5
(ΔVREF)
D5
0
Table 6
. This command includes a start
VREF-
D4
0
XN
YN
XN
XN
and
D3
0
X-axis
Y-axis
Z1 (Pen Pressure)
Z2 (Pen Pressure)
Table 7
D2
0
.
Note
D1
0
[AK4184A]
2008/04
D0
0