Datasheet
Table Of Contents
- Proximity Capacitive Touch Sensor Controller
- 1 Pin Descriptions
- 2 Schematic Drawings and Implementation
- 3 Device Operation Overview
- 4 Electrical Characteristics
- 5 Register Operation Descriptions
- 5.1 Register Read/Write Operations and Measurement Run/Stop Mode
- 5.2 Touch Status Registers (0x00~0x01)
- 5.3 Electrode Filtered Data Register (0x04~0x1D)
- 5.4 Baseline Value Register (0x1E~0x2A)
- 5.5 Baseline Filtering Control Register (0x2B~0x40)
- 5.6 Touch / Release Threshold (0x41~0x5A)
- 5.7 Debounce Register (0x5B)
- 5.8 Filter and Global CDC CDT Configuration (0x5C, 0x5D)
- 5.9 Electrode Charge Current Register (0x5F~0x6B)
- 5.10 Electrode Charge Time Register (0x6C~0x72)
- 5.11 Electrode Configuration Register (ECR, 0x5E)
- 5.12 Out-Of-Range Status Registers (0x02, 0x03)
- 5.13 Soft Rest Register (0x80)
- 5.14 GPIO Registers (0x73~0x7A)
- 6 MPR121 Serial Communication
- Disclaimer
MPR121
Sensors
3 Freescale Semiconductor, Inc.
2 Schematic Drawings and Implementation
Figure 1. Power Configuration 1: MPR121 runs from a 1.71V to 2.75V supply.
Figure 2. Power Configuration 2: MPR121 runs from a 2.0V to 3.6V supply.
20
6
5
1
2
3
4
7
19
18
17
16
15
14
13
12
11
10
9
8
VDD
VDD
ELE11/LED7
GND
0.1 μF
GND
1.71V to 2.75V
VSS
VREG
IRQ
SCL
SDA
ADDR
REXT
ELE10/LED6
ELE9/LED5
ELE8/LED4
ELE7/LED3
ELE6/LED2
ELE5/LED1
ELE4/LED0
ELE3
ELE2
ELE1
ELE0
MPR121Q
TOUCH SENSOR
75 kΩ 1%
20
6
5
1
2
3
4
7
19
18
17
16
15
14
13
12
11
10
9
8
VDD
VDD
ELE11/LED7
GND
0.1 μF
75 kΩ 1%
2.0V to 3.6V
VSS
VREG
IRQ
SCL
SDA
ADDR
REXT
ELE10/LED6
ELE9/LED5
ELE8/LED4
ELE7/LED3
ELE6/LED2
ELE5/LED1
ELE4/LED0
ELE3
ELE2
ELE1
ELE0
MPR121Q
TOUCH SENSOR
GND
GND
0.1 μF