mpr031 Freescale Semiconductor, Inc, mpr031 Datasheet

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... Case Number Touch Pads 1944 (8-Pin UDFN) 3-pads 1944 (8-Pin UDFN) 3-pads 1944 (8-Pin UDFN) 3-pads 1944 (8-Pin UDFN) 3-pads MPR03X Rev 3.0 1/2009 MPR031 MPR032 Capacitive Touch Sensor Controller Bottom View 8-PIN UDFN CASE 1944 Top View 1 8 IRQ/ELE2 SCL ELE1 ...

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Device Overview 1.1 Introduction MPR03X is a small outline, low profile, low voltage touch sensor controller DFN which manages up to three 2 touch pad electrodes interface communicates with ...

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External Signal Description 2.1 Device Pin Assignment Table 1 shows the pin assignment for the MPR03X. For a more detailed description of the functionality of each pin, refer to the appropriate chapter. Table 1. Device Pin Assignment Pin Name ...

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Serial Interface 2 The MPR03X uses Serial Interface. The I Sensor Controller are detailed in the following sections. 2.3.1 Serial-Addressing The MPR03X operates as a slave that sends and receives data through an I Line (SDA) ...

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... SCL The MPR03X monitors the bus continuously, waiting for a START condition followed by its slave address. When a MPR03X recognizes its slave address, it acknowledges and is then ready for continued communication. The MPR031 and MPR032 slave addresses are show in Sensors Freescale Semiconductor Figure 7. Bit Transfer (Figure 8) which the recipient uses to handshake receipt of each byte of data ...

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Message Format for Writing the MPR03X A write to the MPR03X comprises the transmission of the MPR03X’s keyscan slave address with the R/W bit set to 0, followed by at least one byte of information. The first byte of ...

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Operation with Multiple Master The application should use repeated starts to address the MPR03X to avoid bus confusion between I once a master issues a start/repeated start condition, that master owns the bus until a stop condition occurs. If ...

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Functional Overview 3.1 Introduction The MPR03X has an analog front, a digital filter, and a touch recognition system. This data interpretation can be done many different ways but the method used in the MPR03X is explained in this chapter. ...

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Modes of Operation 4.1 Introduction MPR03X’s operation modes are Stop, Run1, and Run2. Stop mode is the start-up and configuration mode. 4.2 Stop Mode In Stop mode, the MPR03X does not monitor any of the electrodes. This mode is ...

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Run1 Mode In Run1 Mode, the MPR03X monitors electrodes which are connected to a user defined array of touch pads. When only electrodes are selected, the IRQ/ELE2 pin is automatically configured as ...

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Table 5. Electrode Configuration Register Field Descriptions Field 6 Calibration Lock – The Calibration Lock bit selects whether calibration is enabled CalLock or disabled. 0 Enabled – In this state baseline calibration is enabled. 1 Disabled – In this state ...

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Output Mechanisms 5.1 Introduction The MPR03X has three outputs: the touch status, values from the second level filter values. The application can either use the touch status or a combination of second level filter data with the baseline data ...

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Filtered Data Each electrode has an associated filtered output. This output is generated through register settings and a low pass filter implementation (Section 8.4). 5.3.1 Filtered Data Low Register The Filtered Data Low register contains the data on each ...

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Baseline Values In addition to the second level filter data, the data from the baseline filter (or third level filter) is also displayed. In this case, the least two significant bits are removed before the 10-bit value is displayed ...

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Interrupts 6.1 Introduction The MPR03X has one interrupt output that is triggered on any touch related event. The interrupts trigger on both the up or down motion of a finger as defined by a set of configurable thresholds. 6.2 ...

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Theory of Operation 7.1 Introduction The MPR03X utilizes the principle that a capacitor holds a fixed amount of charge at a specific electric potential. Both the implementation and the configuration will be described in this section. 7.2 Capacitance Measurement ...

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The valid operating range of the electrode charging source is 0. (voltage visible to the digital interface) range is given by These equations are represented in the graph. In the nominal case of V Table 10. Any ADC ...

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Smaller amounts of change indicate increased sensitivity for the capacitance sensor. Some sample values are shown in In the above cases, the capacitance is assumed ...

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Configuration From the implementation above, there are two elements that can be configured to yield a wide range of capacitance readings ranging from 0.455 pF to 2874.39 pF. The two configurable components are the electrode charge current and the ...

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Filtering 8.1 Introduction The MPR03X has three levels of filtering. The first and second level filters will allow the application to condition the signal for undesired input variation. The third level filter can be configured to reject touch stimulus ...

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Table 13. Filter Configuration Register Field Descriptions Field 7:5 Charge Discharge Time – The Charge Discharge Time field selects the amount CDT of time an electrode charges and discharges. 000 Encoding 0 – Invalid 001 Encoding 1 – Time is ...

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Noise Half Delta Register The Noise Half Delta register is used to set the Noise Half Delta for the third level filter. The address of the Noise Half Delta Register is 0x27 Reset ...

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Touch Detection 9.1 Introduction The MPR03X uses a threshold based system to determine when touches occur. This section will describe that mechanism. 9.2 Thresholds When a touch pad is pressed, an increase in capacitance will be generated. The resulting ...

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Appendix A Electrical Characteristics A.1 Introduction This section contains electrical and timing specifications. A.2 Absolute Maximum Ratings Absolute maximum ratings are stress ratings only, and functional operation at the maxima is not guaranteed. Stress beyond the limits specified in Table ...

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A.4 DC Characteristics This section includes information about power supply requirements and I/O pin characteristics. Table 21. DC Characteristics (Temperature Range = –40°C to 85°C Ambient) V (Typical Operating Circuit ...

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A Characteristics This section includes information about I 2 Table 23 Characteristics V (Typical Operating Circuit +25°C ...

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Appendix B Brief Register Descriptions REGISTER Touch Status Register ELE0 Filtered Data Low Register E0FDL ELE0 Filtered Data High Register E0FDH ELE1 Filtered Data Low Register E1FDL ELE1 Filtered Data High Register E1FDH ELE2 Filtered Data Low Register E2FDL ELE2 ...

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... Appendix C Ordering Information C.1 Ordering Information This section contains ordering information for MPR03X devices. Device Name Temperature Range MPR031EP -40°C to +85°C MPR031EPR2 -40°C to +85°C MPR032EP -40°C to +85°C MPR032EPR2 -40°C to +85°C C.2 Device Numbering Scheme All Proximity Sensor Products have a similar numbering scheme. The below diagram explains what each part number in the family represents ...

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Sensors Freescale Semiconductor PACKAGE DIMENSIONS Preliminary PAGE MPR03X 29 ...

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MPR03X 30 Preliminary PAGE Sensors Freescale Semiconductor ...

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Sensors Freescale Semiconductor Preliminary PAGE MPR03X 31 ...

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... Freescale Semiconductor was negligent regarding the design or manufacture of the part. Freescale™ and the Freescale logo are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © Freescale Semiconductor, Inc. 2009. All rights reserved. ...