AT42QT2120 Datasheet
Table Of Contents
- Features
- 1. Pinouts and Schematics
- 2. Overview
- 3. Wiring and Parts
- 4. I2C-compatible Communications (Comms Mode Only)
- 5. Setups
- 5.1 Introduction
- 5.2 Address 0: Chip ID
- 5.3 Address 1: Firmware Version
- 5.4 Address 2: Detection Status
- 5.5 Addresses 3 – 4: Key Status
- 5.6 Address 5: Slider Position
- 5.7 Address 6: Calibrate
- 5.8 Address 7: Reset
- 5.9 Address 8: Low Power (LP) Mode
- 5.10 Address 9 – 10: Toward Touch and Away from Touch Drift (TTD, ATD)
- 5.11 Address 11: Detection Integrator (DI)
- 5.12 Address 12: Touch Recal Delay (TRD)
- 5.13 Address 13: Drift Hold Time (DHT)
- 5.14 Address 14: Slider Options
- 5.15 Address 15: Charge Time
- 5.16 Address 16 – 27: Detect Threshold (DTHR)
- 5.17 Addresses 28 – 39: Key Control
- 5.18 Addresses 40 – 51: Pulse/Scale for Keys
- 5.19 Address 52 – 75: Key Signal
- 5.20 Address 76 – 99: Reference Data
- 6. Specifications
- Appendix A. I2C-compatible Operation
- Associated Documents
- Revision History
7
9634E–AT42–06/12
AT42QT2120
Figure 1-3. 20-pin VQFN – Comms Mode
Figure 1-4. 20-pin VQFN – Standalone Mode
VSS
VDD
R12
VSS
VDD
SCL
CHANGE
VSS
8
VDD
9
MODE
10
SDA
11
RESET
12
N/C
13
SCL
14
CHANGE
15
SDA
R13
R14
R15
VDD
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
KEY8/GPO6
19
KEY7/GPO5
20
KEY6/GPO4
1
KEY5/GPO3
2
KEY4/GPO2
3
KEY3/GPO1
4
KEY2/GPO0
5
KEY1
6
KEY0
7
KEY11/GPO9
16
KEY10/GPO8
17
KEY9/GPO7
18
KEY 11
KEY 9
KEY 7
KEY 5
KEY 3
KEY 1
KEY 10
KEY 8
KEY 6
KEY 4
KEY 2
KEY 0
May be used for
wheel or slider
VSS
VDD
R6
R5
R4
R3
R2
R1
R0
OUT3
19
OUT2
20
KEY6
1
KEY5
2
KEY4
3
KEY3
4
KEY2
5
GUARD
6
PROX
7
VSS
8
VDD
9
OUT6
16
OUT5
17
OUT4
18
KEY 5
KEY 3
GUARD KEY
KEY 6
KEY 4
KEY 2
PROXIMITY
SENSOR
R12
VDD
MODE
10
N/C
14
RESET
12
PXOUT
13
N/C
15
N/C
11
R13
VDD
VSS
D
1
OUTPUTS