ak4184 AKM Semiconductor, Inc., ak4184 Datasheet - Page 29

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

L
The power down register determines the power down control of the keypad scanner block and touch screen block. The
power down state in the touch screen block (TPPD bit = “1”) holds all of the touch panel driver switches off, so that
current cannot flow through the touch panel. The pen interrupt function is disabled and the PENIRQN pin always
stays “H”, effective for reducing power consumption of the touch screen block.
A power down state in the keypad scanner block (KPPD bit = “1”) holds all the C1 ~ C6 pins outputs “L”. By setting
this bit = “1” stops key scanning and clears the keypad data register (KPDATA1, KPDATA2). The keypad function is
restored after the keypad scanner block is powered up. The keypad interrupt is disabled at power-down.
The power down control register format is shown here.
MS0603-E-00
Addr
08H
Power Down Register (PAGE 1)
PDCTRL
NAME
Bits
15:2
1
0
Name
KPPD
TPPD
D15
0
D14
0
Description
Reserved
Enable keypad block power up/down
0 : power up(default)
1 : power down
Enable the touch screen control block power up/down
0 : power up(default)
1 : power down
D13
0
Table 37. Power Down Register Format
D12
0
Table 38. Power Down Register
D11
0
D10
0
29
D9
0
D8
0
D7
0
D6
0
D5
0
D4
0
D3
0
D2
0
KPPD
D1
2007/04
[AK4184]
TPPD
D0