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
2 Freescale Semiconductor, Inc.
1 Pin Descriptions
Table 1. Pin Descriptions
Pin No.
Pin Name Description
1 IRQ Open Collector Interrupt Output Pin, active low
2
SCL
I
2
C Clock
3
SDA
I
2
C Data
4
ADDR
I
2
C Address Select Input Pin. Connect the ADDR pin to the VSS, VDD, SDA or SCL line, the resulting I
2
C addresses
are 0x5A, 0x5B, 0x5C and 0x5D respectively
5
VREG Internal Regulator Node – Connect a 0.1 μF bypass cap to VSS
6
VSS Ground
7
REXT External Resistor – Connect a 75 kΩ 1% resistor to VSS to set internal reference current
8 ELE0 Electrode 0
9
ELE1 Electrode 1
10
ELE2 Electrode 2
11 ELE3 Electrode 3
12
ELE4 Electrode 4
13
ELE5 Electrode 5
14 ELE6 Electrode 6
15
ELE7 Electrode 7
16
ELE8 Electrode 8
17
ELE9 Electrode 9
18 ELE10 Electrode 10
19
ELE11 Electrode 11
20
VDD Connect a 0.1 μF bypass cap to VSS