ak4184 AKM Semiconductor, Inc., ak4184 Datasheet - Page 16

• Manufacturer Part Number: ak4184
• Description: Tsc With Keypad Scanner And Gpio Expander
• Manufacturer: AKM Semiconductor, Inc.

L
Upon power-up, all blocks of the AK4184 should be reset by executing 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.
L
The control command (4 bits) provided to the AK4184 via DIN is shown in
channel selection of ADC input, power-down mode of ADC and the next 12bits (written by “0” data). The AK4184
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 as shown in
MS0603-E-00
System Reset
Touch Screen Control Command
14:13
D15
Bits
11:0
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. (Table 7)
Power-down Mode (Table 8)
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
OFF
OFF YN(Z2)
YN
ON
D9
0
XP(Z1)
AIN+
ADC input
YP
XP
16
( AIN)
D8
0
Table 6
AIN-
D7
Function
XN
YN
XN
XN
0
and
D6
0
Reference Voltage
VREF+
Table 7
XP
YP
YP
YP
Table 5
( VREF)
D5
0
.
. This command includes a start bit,
VREF-
D4
0
XN
YN
XN
XN
D3
0
X-axis
Y-axis
Z1 (Pen Pressure)
Z2 (Pen Pressure)
D2
0
Note
D1
0
2007/04
[AK4184]
D0
0