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
10 Freescale Semiconductor, Inc.
4.5 I
2
C AC Characteristics
Table 7. I
2
C AC Characteristics
(Typical Operating Circuit, V
DD
and V
REG
= 1.8V, T
A
= 25°C, unless otherwise noted.)
Parameter Symbol Conditions Min Typ Max Units
Serial Clock Frequency
f
SCL
400 kHz
Bus Free Time Between a STOP and a START Condition
t
BUF
1.3 μs
Hold Time, (Repeated) START Condition
t
HD, STA
0.6 μs
Repeated START Condition Setup Time
t
SU, STA
0.6 μs
STOP Condition Setup Time
t
SU, STO
0.6 μs
Data Hold Time
t
HD, DAT
0.9 μs
Data Setup Time
t
SU, DAT
100 ns
SCL Clock Low Period
t
LOW
1.3 μs
SCL Clock High Period
t
HIGH
0.7 μs
Rise Time of Both SDA and SCL Signals, Receiving
t
R
20+0.1C
b
300 ns
Fall Time of Both SDA and SCL Signals, Receiving
t
F
20+0.1C
b
300 ns
Fall Time of SDA Transmitting
t
F.TX
20+0.1C
b
250 ns
Pulse Width of Spike Suppressed
t
SP
25 ns
Capacitive Load for Each Bus Line
C
b
400 pF