AT42QT2161-MMU Atmel, AT42QT2161-MMU Datasheet - Page 26

• Manufacturer Part Number: AT42QT2161-MMU
• Description: IC TOUCH SENSOR 16KEY QFN M-MOD
• Manufacturer: Atmel
• Type: Capacitiver

Specifications of AT42QT2161-MMU

• Touch Panel Interface: 8, 2-Wire
• Number Of Inputs/keys: 16 Key, Slider
• Resolution (bits): 10 b
• Data Interface: I²C, Serial
• Voltage Reference: Internal
• Voltage - Supply: 1.8 V ~ 5.5 V
• Current - Supply: 1.14mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.4
6.5
26
Address 2: General Status
Address 3 – 4: Key Status
AT42QT2161
Table 6-4.
Table 6-5.
These bits indicate the general status of the device. A change in this byte will cause the
CHANGE line to trigger.
RESET: this bit is set after a reset. This bit is clear after this byte is read back by the host.
CYCLE OVERRUN: this bit is set if the cycle time is more than 16 ms. It will be cleared when the
cycle time is less than 16 ms.
Note: holding any of the
increase the cycle time.
CC: this common change bit is set if all the selected keys (address 78 – 79) have a signal
change of more than half the detection threshold, NTHR. The CC bit is not debounced.
This bit can be used to indicate a common change in signals, e.g. In a notebook application,
where the cover is closing, so that the host can suppress key detections.
Note: the CC bit will be set to 1 if no keys are selected to be in the Common Change group (see
Section 6.27 on page
SDET: this bit is set if a touch is detected on the slider.
Address 3: detect status for keys 0 to 7
Address 4: detect status for keys 8 to 15
Each location indicates all keys in detection, if any, as a bitfield; touched keys report as “1”,
untouched or disabled keys report as “0”. A change in this byte will cause the CHANGE line to
trigger.
Address
Address
2
3
4
General Status
Key Status and Numbering
RESET
k15
b7
b7
k7
36).
CYCLE
OVER
I
RUN
2
k14
b6
b6
k6
C
-compatible lines, for clock stretching or other purposes, will
k13
b5
b5
k5
0
k12
b4
b4
k4
0
k11
b3
b3
k3
0
k10
b2
b2
k2
0
CC
b1
b1
k1
k9
9614A–AT42–08/10
SDET
b0
b0
k0
k8