MPR121QR2 Freescale Semiconductor, MPR121QR2 Datasheet
MPR121QR2
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MPR121QR2 Summary of contents
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... Remote Controls • Mobile Phones • Lighting Controls Device Name Temperature Range MPR121QR2 -40°C to +85°C This document contains a product under development. Freescale Semiconductor reserves the right to change or discontinue this product without notice. © Freescale Semiconductor, Inc., 2009, 2010. All rights reserved ...
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... External Resistor – 75 kΩ ELE0 Electrode 0 ELE1 Electrode 1 ELE2 Electrode 2 ELE3 Electrode 3 ELE4 Electrode 4 (LED0) ELE5 Electrode 5 (LED1) ELE6 Electrode 6 (LED2) ELE7 Electrode 7 (LED3) ELE8 Electrode 8 (LED4) ELE9 Electrode 9 (LED5) ELE10 Electrode 10 (LED6) ELE11 Electrode 11 (LED7) VDD VDD Sensors Freescale Semiconductor ...
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... SCL 3 SDA 4 ADDR 7 REXT 0.1 μF 75 kΩ 1% GND GND GND MPR121Q TOUCH SENSOR 19 ELE11/LED7 18 ELE10/LED6 17 ELE9/LED5 16 ELE8/LED4 15 ELE7/LED3 14 ELE6/LED2 13 ELE5/LED1 12 ELE4/LED0 11 ELE3 10 ELE2 9 ELE1 8 ELE0 19 ELE11/LED7 18 ELE10/LED6 17 ELE9/LED5 16 ELE8/LED4 15 ELE7/LED3 14 ELE6/LED2 13 ELE5/LED1 12 ELE4/LED0 11 ELE3 10 ELE2 9 ELE1 8 ELE0 Sensors Freescale Semiconductor ...
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... AN3895. For reference the register map of the MPR121 is included in MPR121 4 ” electrode will be included at the end of a normal detection cycle and will have its own 2 C) compliant device with an additional interrupt that is triggered any time a touch address by connecting the ADDR pin to the VSS, VDD, SDA Table 1. Sensors Freescale Semiconductor ...
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... ELE8 Baseline Value ELE9 Baseline Value ELE10 Baseline Value ELE11 Baseline Value ELEPROX Baseline Value MHD Rising NHD Amount Rising NCL Rising FDL Rising MHD Falling NHD Amount Falling Sensors Freescale Semiconductor Fields ELE6 ELE5 ELE4 ELE3 ELE2 ELEPROX ELE11 ELE10 ELE6 ELE5 ...
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... DT 0x5B 0x00 0x5C 0x10 ESI 0x5D 0x04 EleEn 0x5E 0x00 0x5F 0x00 0x60 0x00 0x61 0x00 Sensors Freescale Semiconductor ...
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... GPIO Data Clear Register CLR11 GPIO Data Toggle Register TOG11 AUTO-CONFIG Control Register 0 AFES AUTO-CONFIG Control Register 1 SCTS AUTO-CONFIG USL Register AUTO-CONFIG LSL Register AUTO-CONFIG Target Level Register Sensors Freescale Semiconductor Fields CDC3 CDC4 CDC5 CDC6 CDC7 CDC8 CDC9 CDC10 CDC11 CDCPROX ...
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... Machine Model (MM) Charge Device Model (CDM) Latch-up current 85°C A MPR121 Symbol Value V -0 -0.3 to +2.75 REG 0 0 - GPIO i 1.2 GPIO T -40 to +125 S Symbol Value V ±2000 ESD V ±200 ESD V ±500 ESD I ±100 LATCH Unit ° °C Unit Sensors Freescale Semiconductor ...
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... Operating Circuit, V and V DD REG Parameter 8 MHz Internal Oscillator 1 kHz Internal Oscillator Sensors Freescale Semiconductor = 1 25°C, unless otherwise noted.) A Conditions Run1 Mode @ 1 ms sample period Run1 Mode @ 2 ms sample period Run1 Mode @ 4 ms sample period Run1 Mode @ 8 ms sample period ...
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... SU, STO t HD, DAT t SU, DAT t LOW t HIGH F. Min Typ Max Units 400 kHz μs 1.3 μs 0.6 μs 0.6 μs 0.6 μs 0.9 100 ns μs 1.3 μs 0.7 20+0.1C 300 ns b 20+0.1C 300 ns b 20+0.1C 250 400 pF Sensors Freescale Semiconductor ...
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... V and charges up with a slope, Equation trodes are grounded during this measurement. At the end of time T, the electrode voltage is measured with a 10 bit ADC. The voltage is inversely proportional to capacitance according to same rate it was charged. Sensors Freescale Semiconductor 1st 2nd FILTER FILTER 1 - 128 μ 2048 μ ...
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... V). This means that for a given ------------ 1024 , ADC low = V DD and V – 0 ADC high = ------------------------- - 1024 1.8 V the ADC range is shown below ADC ADC ADC DD high low 1.8 625.7778 398.2222 2T 2.51 2.71 the valid DD Equation 3 Equation 4 Table mid 512 Sensors Freescale Semiconductor 7. ...
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... In the previous cases, the capacitance is assumed the middle of the range for specific settings. Within the capacitance range the equation is nonlinear, thus the sensitivity is best with the lowest capacitance. This graph shows the sensitivity derivative reading across the valid range of capacitances for a set I, T, and V 21 pF) and a nominal 1.8 V supply. Figure 7 Sensors Freescale Semiconductor × × ...
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... Encoding 0 – Disables Electrode Charging 000001 Encoding 1 – Sets the current to 1μA ~ 111111 Encoding 63 – Sets the current to 63 μA MPR121 14 C/ADC Minimum Capacitance Figure CDC Figure 8. AFE Configuration Register Description Maximum Sensors Freescale Semiconductor ...
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... Electrode # Charge Discharge Current – The Charge Discharge Current field CDC selects the supply current to be used when charging and discharging an electrode. 000000 Encoding 0 – Disables Electrode Charging 000001 Encoding 1 – Sets the current to 1μA ~ 111111 Encoding 63 – Sets the current to 63 μA Sensors Freescale Semiconductor SFI 0 0 ...
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... Figure 11. Electric Charge Time Register Description - 0.7 V due to this being a non-linear region. Thus the 0.7 V ADC DD DD 1.8 V 1.1 V 625 V 2.3 V 785 DD in the system. If the voltage is unregulated, set the values CDT Baseline 156 196 is 1.8 V and 196 when V DD Sensors Freescale Semiconductor is DD ...
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... As this register represents the upper limit for the auto-configuration the value can be calculated by: For the 1.8 V system, this value is 156 or 0x9C. AUTO-CONFIG TARGET LEVEL REGISTER Reset Unimplemented Figure 13. AUTO-CONFIG Target Level Register Sensors Freescale Semiconductor USL Figure 12. AUTO-CONFIG USL Register Description V DD 0.7 – ...
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... AUTO-CONFIG CONTROL REGISTER 7 R AFES W Reset Unimplemented MPR121 18 Description V DD 0.7 – ⋅ ⋅ ------------------------- - 256 0 LSL Figure 14. AUTO-CONFIG LSL Register Description V – 0.7 DD ⋅ ⋅ ------------------------- - 256 0. RETRY BVA Figure 15. AUTO-CONFIG Control Register 90% of USL 65% of USL ARE ACE Sensors Freescale Semiconductor ...
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... The ARFF and ACFF also tell the user which type of configuration cycle caused the error was triggered during an initial calibration, the ACFF will trigger. If the fail occurs during a reconfiguration, the ARFF will trigger. ELE0-7 OUT OF RANGE STATUS REGISTER 7 R E7S W Reset Unimplemented Figure 16. ELE0-7 Out Of Range Status Register Sensors Freescale Semiconductor Description E6S E5S E4S E3S 0 0 ...
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... Electrode 1 OOR Status – The Electrode 7 OOR Status shows if the AUTO-CONFIG has failed. E1S 0 – Auto-configuration Successful 1 – Auto-configuration Failed 0 Electrode 0 OOR Status – The Electrode 7 OOR Status shows if the AUTO-CONFIG has failed. E0S 0 – Auto-configuration Successful 1 – Auto-configuration Failed MPR121 20 Description Freescale Semiconductor Sensors ...
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... Electrode 9 OOR Status – The Electrode 9 OOR Status shows if the AUTO-CONFIG has failed – Auto-configuration Successful E9S 1 – Auto-configuration Failed Electrode 8 OOR Status – The Electrode 8 OOR Status shows if the AUTO-CONFIG has failed – Auto-configuration Successful E8S 1 – Auto-configuration Failed Sensors Freescale Semiconductor E11S E10S ELEPROXS 0 0 ...
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... The AFE Configuration Register is used to set both the CDC and the number of samples taken in the lowest level filter. The address of the AFE Configuration Register is 0x5C FFI W Reset Unimplemented MPR121 22 1st 2nd FILTER FILTER 1 - 128 μ 2048 μs STATUS REGISTER Figure 18. Data Flow in the MPR121 CDC Figure 19. AFE Configuration Register BASELINE FILTER TOUCH IRQ Sensors Freescale Semiconductor ...
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... The first level of filtering delivers data to a second filter stage. The second filter stage averages samples over more time, in this example anywhere from 128 ms. Then a value can be selected for how many samples should be averaged. FILTER CONFIGURATION REGISTER 7 R CDT W Reset Unimplemented Sensors Freescale Semiconductor Description FFI μs 6 μs TIME Figure 20. 6 ...
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... First Filter From this, it can be seen that the 12 μs up time from the 1 ms samples results in a very low percent of duty cycle. This results in a very low average current consumption. MPR121 24 Description Figure 22 illustrates this adjustment TIME (ms) Figure 22 Sensors Freescale Semiconductor ...
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... At each 64 ms, a decision would be made regarding touch by com- paring the Baseline with the filtered data output, resulting worst case of the full 64 ms plus half the previous cycle, equalling 96 ms. Sensors Freescale Semiconductor 199 μA 102 μA 54 μA 29 μ ...
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... Encoding 1 – Sets the Max Half Delta 111111 Encoding 63 – Sets the Max Half Delta to 63 MPR121 26 1st 2nd FILTER FILTER 1 - 128 μ 2048 μs STATUS REGISTER Figure 24. Data Flow in the MPR121 MHD Description BASELINE FILTER TOUCH IRQ Sensors Freescale Semiconductor ...
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... Encoding 0 – Sets the Noise Count Limit to 1 (every time over Max Half Delta) 00000001 Encoding 1 – Sets the Noise Count Limit to 2 consecutive samples over Max Half Delta ~ 11111111 Encoding 255 – Sets the Noise Count Limit to 255 consecutive samples over Max Half Delta Sensors Freescale Semiconductor ...
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... MHD of one, then the baseline filter would increase to equal the data for the next cycle. MHD = 1 MPR121 FDL Figure 27. Filter Delay Limit Register Description nd filter data and the baseline filter value. The occurrence filter data is less than the baseline filter data. The rising data system is enabled Figure 28. Max Half Delta Baseline Data Sensors Freescale Semiconductor ...
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... Low frequency changes to the data can trick the filter in some instances. The FDL is also available to slow down the overall system. This is done by taking an average of the specified number of values before running them through the baseline filter. Sensors Freescale Semiconductor Case 1 comes into effect ...
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... B. The baseline quickly snaps back to the initial value by having fast filtering in the positive direction C. The repeated touch is easily handled since the baseline quickly adjusted was slow, the second touch would have resulted in a possible false negative for a touch detection. MPR121 30 Case Figure 32 Figure 33. Case 1 Baseline Data Averaged 3 Data Baseline Data Sensors Freescale Semiconductor ...
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... A A. The touch is detected which disengages the increasing/decreasing baseline filter but leaves it enabled with very slow filtering B. Even though the touch has not been released it times out and is eventually rejected. C. Normal baseline filter is engaged. Sensors Freescale Semiconductor C B Figure 34 Figure 35. ...
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... The same applies to water, food humid environments and other instances that generate capacitance change Valid normal touch B. False touch filtered out C. Touch from new adjusted baseline MPR121 Figure 36. Baseline Data Sensors Freescale Semiconductor ...
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... To clear the interrupt all you must do is initiate a I2C communication, with the intent that you read register 0x00 and 0x01 to determine which electrodes are touched. Sensors Freescale Semiconductor 1st 2nd FILTER FILTER 1 - 128 μ ...
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... Electrode 1 Status – The Electrode 1 Status bit shows touched or not touched. E1S 0 – Not Touched 1 – Touched 0 Electrode 0 Status – The Electrode 0 Status bit shows touched or not touched. E0S 0 – Not Touched 1 – Touched MPR121 E6S E5S E4S E3S Figure 38. Touch Status Register 0 Description E2S E1S E0S Sensors Freescale Semiconductor ...
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... Reset Unimplemented Table 28. Filtered Data High Register Field Descriptions Field 7:0 Filtered Data High Bits – The Filtered Data High Bits displays the higher 2 bits of FDHB the 10 bit filtered A/D reading. 00 Encoding Encoding 3 Sensors Freescale Semiconductor EPROXS E11S Figure 39. Touch Status Register1 Description ...
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... Internally to the device, the full 10-bit value is stored, but as this level of precision is not necessary as the low two bits are disregarded for output. The Touch Threshold is a user defined value. There is both a touch and an un-touch threshold to provide hysteresis. MPR121 FDLB Figure 41. Filtered Data Low Register Description Figure 42. Filtered Data High Register Description Baseline = Baseline Value • Sensors Freescale Semiconductor ...
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... RELEASE THRESHOLD REGISTER Reset Unimplemented Table 32. Release Threshold Register Field Descriptions Field 7:0 Release Threshold – The Release Threshold Byte sets the trip point for detecting RTH a touch. 00000000 Encoding 0 ~ 11111111 Encoding 255 Sensors Freescale Semiconductor TTH Figure 43. Touch Threshold Register Description RTH ...
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... Additional filtering can be done before the data gets to the touch detection system. Refer to Freescale Application Note AN3890. MPR121 38 Delta = Baseline - Data → Delta > Touch Threshold Trigger Touch → Trigger Release Delta < Touch Threshold Description Sensors Freescale Semiconductor ...
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... Proximity Detection electrode. Table 35. Eleprox Electrode Register 0x1C, 0x2D (Reset Default: 0x00, 0x00) Bit7 Bit6 0x1C D7 D6 Bit7 Bit6 0x1D — — Sensors Freescale Semiconductor th pseudo Electrode) before all the independent electrodes touch Bit5 Bit4 Bit3 AD[1] AD[0] EC[ EC1 EC0 x x Area Detection by connecting ELE0~1 ...
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... Bit3 DR[1] DR[0] X Bit5 Bit4 Bit3 Bit5 Bit4 Bit3 Proximity Detection Bit2 Bit1 Bit0 Bit2 Bit1 Bit0 ELE[2] ELE[1] ELE[0] Bit2 Bit1 Bit0 ELE[10] ELE[9] ELE[8] Bit2 Bit1 Bit0 DT[2] DT[1] DT[0] Bit2 Bit1 Bit0 Bit2 Bit1 Bit0 Sensors Freescale Semiconductor ...
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... It’s recommended that Auto-Configuration is used for design efficiency if proximity sensing works properly in this way. Refer to Freescale application note AN3889 for details of the Auto-Configuration function. Sensors Freescale Semiconductor Table 41 shows an example setting for proximity sensing, the concept is to have quickest Register Address ...
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... Refer to Freescale application note AN3863 for more detailed discussion on electrode and layout design considerations. MPR121 42 Bit5 Bit4 Bit3 SFI[1:0] Bit5 Bit4 Bit3 CDC[4:0] Bit2 Bit1 Bit0 ESI[2:0] Bit2 Bit1 Bit0 Sensors Freescale Semiconductor ...
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... When these multifunction pins are not configured as electrodes, they may be used to drive LED or for general GPIO purpose. PIN # ELECTRODE ELE0 ELE1 ELE2 GPIO — — — VDD 1. 2.75 V Figure 46. Configuration 1: MPR121 runs from a 1. 2.75 V supply. Sensors Freescale Semiconductor ELE3 ELE4 ELE5 ELE6 ELE7 — GPIO0 GPIO1 GPIO2 GPIO3 VDD 1. 2.75 V 0.1 μF ...
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... ELE4/LED0 11 ELE3 10 ELE2 9 ELE1 8 ELE0 MPR121Q CTL0[3] CTL0[2] CTL0[1] CTL0[0] CTL1[3] CTL1[2] CTL1[1] CTL1[0] DAT[3] DAT[2] DAT[1] DAT[0] DIR[3] DIR[2] DIR[1] DIR[0] EN[3] EN[2] EN[1] EN[0] SET[3] SET[2] SET[1] SET[0] CLR[3] CLR[2] CLR[1] CLR[0] TOG[3] TOG[2] TOG[1] TOG[0] Sensors Freescale Semiconductor ...
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... PWM 3 PWM7[3] PWM7[2] 0x84 Sensors Freescale Semiconductor DESCRIPTION GPIO function is disabled. Port is high-z state. GPIO port becomes input port. GPIO port becomes input port with internal pull-down. GPIO port becomes input port with internal pull-up. Not defined yet (as same as CTL = 00). ...
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... The PWM duty is not so much accurate, because GPIO output transition (include PWM) inhibits during measurement state. Therefore, when interval time (=Touch Detection Sample Interval) is close to measurement time (depends on charge time, AFE Samples and number of measurement electrodes), the PWM operation is disturbed and the waveform couldn’t keep programmed duty. MPR121 46 Description (_ is 0~7) Freescale Semiconductor Sensors ...
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... STOP (P) condition by transitioning SDA from low to high while SCL is high. The bus is then free for another transmission. SDA DATA LINE STABLE SCL DATA VALID Sensors Freescale Semiconductor 2 C protocol implementation and the specifics of communicating with the Touch (Figure 48) sent by a master, followed by the MPR121’s 7-bit slave address t SU STA t HD STA ...
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... The bit following the 7-bit slave address (bit eight) is the R/W bit, which Figure 52. Slave Address Table 46. Table 46. 2 ADDR Pin Connection I C Address VDD 0x4C VSS 0x4D SDA 0x4E SCL 0x4F P STOP CONDITION clock pulse, and the recipient pulls down SDA CLOCK PULSE FOR R/W ACK Freescale Semiconductor Sensors ...
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... An address may always be rewritten 2 to fix this problem. Follow I C protocol for multiple master configurations. Sensors Freescale Semiconductor (Figure 53) beyond storing the command byte. Any bytes received after the D15 D14 ...
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... AN3944: MPR121 Quick Start Guide INTRODUCTION The MPR121 is Freescale Semiconductor’s top of the line touch sensor and can fit into a wide range of applications. These applications can all be accommodated by having a device a with a very large range of flexibility. While all of these added features can allow for a wide range of flexibility, they can also add an unnecessary layer of complication. For advanced users who want to do more than basic touch detection, additional information can be found in other application notes ...
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... Variation: As the filter is sensitive to setting changes recommended that users read AN3891 before changing the values. In most cases these default values will work Sensors Freescale Semiconductor Register Name Register Name Register Name Value ...
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... AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 0x0F AN3892 0x0A AN3892 Value Application Note 0x04 AN3890 Sensors Freescale Semiconductor ...
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... Variation: In most cases these values will never need to be change, but if a case arises, a full description is found in application note AN3889. CONCLUSION In many applications for the MPR121, the default settings presented in this document will be sufficient for both design time activities as well as in the production implementation. Sensors Freescale Semiconductor Register Name Register Name Value Application Note 0x0C ...
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... MPR121 54 PACKAGE DIMENSIONS PAGE Sensors Freescale Semiconductor ...
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... Sensors Freescale Semiconductor PAGE MPR121 55 ...
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... MPR121 56 PACKAGE DIMENSIONS PAGE Sensors Freescale Semiconductor ...
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... Freescale Semiconductor product could create a situation where personal injury or death may occur. Should Buyer ...