Preliminary

TTP223

08’/04/07

Page 4 of 11

Ver :1.0

FUNCTION DESCRIPTION

1. Sensitivity adjustment

The total loading of electrode size and capacitance of connecting line on PCB can affect the

sensitivity. So the sensitivity adjustment must according to the practical application on PCB. The

TTP223 offers some methods for adjusting the sensitivity outside.

1-1 by the electrode size

Under other conditions are fixed. Using a larger electrode size can increase sensitivity. Otherwise it

can decrease sensitivity. But the electrode size must use in the effective scope.

1-2 by the panel thickness

Under other conditions are fixed. Using a thinner panel can increase sensitivity. Otherwise it can

decrease sensitivity. But the panel thickness must be below the maximum value.

1-3 by the value of Cs (please see the down figure)

Under other conditions are fixed. When do not use the Cs to VSS, the sensitivity is most sensitive.

When adding the values of Cs will reduce sensitivity in the useful range (0≦Cs≦50pF).

RST

SLRFTB

LPMB

MOTB

AHLB

TOG

OPDO

Q

ELECTRODE

Cs

I

VSS

VDD

VDD

2. Output mode

The TTP223 has direct mode active high or low by AHLB pad option. And has toggle mode by

TOG pad option. Another has open drain mode by bonding option. Pad Q is digital output, pad

OPDO is open drain output.

TOG

AHLB

Pad Q option features

Pad OPDO option features

0

0

Direct mode,

CMOS active high output

Direct mode,

Open drain active high output

0

1

Direct mode,

CMOS active low output

Direct mode,

Open drain active low output

1

0

Toggle mode,

Power on state=0

Toggle mode,

Power on state high-Z, Active high

1

1

Toggle mode,

Power on state=1

Toggle mode,

Power on state high-Z, Active low