CAP1128 datasheet(27/75 Pages) MICROCHIP

27 / 75 page

 2015 Microchip Technology Inc.

DS00001622B-page 27

CAP1128

When the repeat rate is enabled, the device uses an additional control called MPRESS that determines whether a touch

is flagged as a simple “touch” or a “press and hold”. The MPRESS[3:0] bits set a minimum press timer. When the button

is touched, the timer begins. If the sensor pad is released before the minimum press timer expires, it is flagged as a

touch and an interrupt is generated upon release. If the sensor input detects a touch for longer than this timer value, it

is flagged as a “press and hold” event. So long as the touch is held, interrupts will be generated at the programmed

repeat rate and upon release (if enabled).

APPLICATION NOTE: Figure 5-2 and Figure 5-3 show default operation which is to generate an interrupt upon

sensor pad release and an active-low ALERT# pin.

APPLICATION NOTE: The host may need to poll the device twice to determine that a release has been detected.

FIGURE 5-2:

Sensor Interrupt Behavior - Repeat Rate Enabled

FIGURE 5-3:

Sensor Interrupt Behavior - No Repeat Rate Enabled

Touch Detected

INT bit

Button Status

Write to INT bit

Polling Cycle

(35ms)

Min Press Setting

(280ms)

Interrupt on

Touch

Button Repeat Rate

(175ms)

Button Repeat Rate

(175ms)

Interrupt on

Release

(optional)

ALERT# pin

(active low)

Touch Detected

INT bit

Button Status

Write to INT bit

Polling Cycle

(35ms)

Interrupt on

Touch

Interrupt on

Release

(optional)

ALERT# pin

(active low)

CAP1128 Datasheet(PDF) 27 Page - Microchip Technology

CAP1128 Datasheet(HTML) 27 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

Datasheet Download

Link URL