mpr083 Freescale Semiconductor, Inc, mpr083 Datasheet - Page 5

• Manufacturer Part Number: mpr083
• Description: Proximity Capacitive Touch Sensor Controller
• Manufacturer: Freescale Semiconductor, Inc

Sensors
Freescale Semiconductor
The remaining 5 connections are SCL, SDA, IRQ, ATTN, and SOUNDER. Depending on the specific application, each of these
control lines can be used by connecting them to a host system. In the most minimal system, the SCL and SDA must be connected
to a master I
in
Note that in this configuration the AD0 address line is tied high thus the slave address of the MPR083 0x4D. Alternatively the
address line can be pulled low if the host system needs the MPR083 to be on address 0x4C. This functionality can also be used
to incorporate two MPR083 devices in the same system.
2.3
The MPR083 uses an I
Sensor Controller are detailed in the following sections.
2.3.1
The MPR083 operates as a slave that sends and receives data through an I
line (SDA) and a serial clock line (SCL) to achieve bi-directional communication between master(s) and slave(s). A master
(typically a microcontroller) initiates all data transfers to and from the MPR083, and generates the SCL clock that synchronizes
the data transfer.
The MPR083 SDA line operates as both an input and an open-drain output. A pull-up resistor, typically 4.7k, is required on SDA.
The MPR083 SCL line operates only as an input. A pull-up resistor, typically 4.7k, is required on SCL if there are multiple
masters on the 2-wire interface, or if the master in a single-master system has an open-drain SCL output.
Each transmission consists of a START condition
R/W bit, a register address byte, one or more data bytes, and finally a STOP condition.
Figure
Serial Interface
Serial-Addressing
4.
GND
V DD
SDA
SCL
t HD STA
2
1μF
C interface to communicate with the MPR083. All of the connections for the MPR083 are shown by the schematic
V DD
CONDIT ION
4.7k Ω
ST ART
2
C Serial Interface. The I
ATTN
IRQ
SCL
SDA
SOUNDER
t LOW
Figure 4. Recommended System Connections Schematic
t R
1
2
3
4
5
6
7
8
t HIGH
t SU DAT
ATTN
IRQ
VDD
VSS
SCL
SDA
AD0
SOUNDER
MPR083
Figure 5. Wire Serial Interface Timing Details
t F
t HD DAT
2
C protocol implementation and the specifics of communicating with the Touch
(Figure
E1
E2
E3
E4
E5
E6
E7
E8
V DD
16
15
14
13
12
11
10
9
5) sent by a master, followed by the MPR083’s 7-bit slave address plus
t SU STA
780k Ω
REPEAT ED ST ART
780k Ω
CONDIT ION
780k Ω 780k Ω 780k Ω
2
C 2-wire interface. The interface uses a serial data
t HD STA
t SU STO
780k Ω 780k Ω 780k Ω
CONDIT ION
GND
ST OP
t BUF
ELECTRODE
8-POSITION
1
2
3
4
5
6
7
8
9
ROTARY
CONDIT ION
ARRAY
E1
E2
E3
E4
E5
E6
E7
E8
GND
ST ART
MPR083
5