AD7147PACPZ-1RL Analog Devices Inc, AD7147PACPZ-1RL Datasheet
AD7147PACPZ-1RL
Specifications of AD7147PACPZ-1RL
Related parts for AD7147PACPZ-1RL
AD7147PACPZ-1RL Summary of contents
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FEATURES Programmable capacitance-to-digital converter (CDC) Femtofarad resolution 13 capacitance sensor inputs 9 ms update rate, all 13 sensor inputs No external RC components required Automatic conversion sequencer On-chip automatic calibration logic Automatic compensation for environmental changes Automatic adaptive threshold and ...
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AD7147 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Average Current Specifications .................................................. 4 SPI Timing Specifications (AD7147) ......................................... ...
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SPECIFICATIONS 2 3 − +85°C, unless otherwise noted Table 1. Parameter CAPACITANCE-TO-DIGITAL CONVERTER Update Rate Resolution CINx Input Range No Missing Codes CINx Input Leakage Maximum Output Load ...
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AD7147 AVERAGE CURRENT SPECIFICATIONS Table 2. Typical Average Current in Low Power Mode Low Power Decimation Mode Delay Rate 1 200 ms 64 20.83 128 25.3 256 34.11 400 ms 64 18.17 128 20.43 256 24.9 600 ms 64 17.28 ...
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SPI TIMING SPECIFICATIONS (AD7147 −40°C to +85°C, sample tested at 25°C to ensure compliance noted. All input signals are specified with t Table 4. SPI Timing Specifications Parameter Limit f 5 SCLK ...
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AD7147 TIMING SPECIFICATIONS (AD7147- −40°C to +85°C, sample tested at 25°C to ensure compliance noted. All input signals timed from a voltage level of 1 Table Timing ...
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ABSOLUTE MAXIMUM RATINGS Table 6. Parameter V to GND CC Analog Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND 1 Input Current to Any Pin Except Supplies ESD Rating (Human Body Model) Operating Temperature ...
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AD7147 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS PIN 1 INDICATOR CIN6 1 CIN7 2 CIN8 3 AD7147 CIN9 4 TOP VIEW CIN10 5 (Not to Scale) CIN11 6 NOTES 1. THE EXPOSED PAD IS NOT CONNECTED INTERNALLY. FOR INCREASED RELIABILITY OF ...
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TYPICAL PERFORMANCE CHARACTERISTICS 935 915 895 DECIMATION = 64 875 DECIMATION = 128 855 835 815 795 2.6 2.7 2.8 2.9 3.0 3.1 3.2 V (V) CC Figure 7. Supply Current vs. Supply Voltage 180 200ms 160 140 120 100 ...
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AD7147 58000 56000 54000 52000 50000 48000 46000 44000 42000 40000 0 100 200 300 AC CAPACITIVE LOAD (pF) SHIELD Figure 13. Output Code vs. Capacitive Load on AC 960 940 3.6V 920 900 3.3V 880 860 840 820 2.6V ...
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THEORY OF OPERATION The AD7147 and AD7147-1 are CDCs with on-chip environ- mental compensation. They are intended for use in portable systems requiring high resolution user input. The internal circuitry consists of a 16-bit, ∑-Δ converter that can change a ...
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AD7147 Registering a Sensor Activation When a user approaches a sensor, the total capacitance associated with that sensor changes and is measured by the AD7147. If the change causes a set threshold to be exceeded, the AD7147 interprets this as ...
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Full Power Mode In full power mode, all sections of the AD7147 remain fully powered and converting at all times. While a sensor is being touched, the AD7147 processes the sensor data sensor is touched, the AD7147 measures ...
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AD7147 CAPACITIANCE-TO-DIGITAL CONVERTER The capacitance-to-digital converter on the AD7147 has a Σ-Δ architecture with 16-bit resolution. There are 13 possible inputs to the CDC that are connected to the input of the converter through a switch matrix. The sampling frequency ...
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A button sensor generally requires one sequencer stage; this is shown in Figure 26 as B1. However possible to configure two button sensors to operate differentially for one conversion stage. Only one button can be activated at a ...
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AD7147 CDC CONVERSION SEQUENCE TIME Table 10. CDC Conversion Times for Full Power Mode SEQUENCE_STAGE_NUM Decimation = 64 0 0.768 1 1.536 2 2.304 3 3.072 4 3.84 5 4.608 6 5.376 7 6.144 8 6.912 9 7.68 10 8.448 ...
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CAPACITANCE SENSOR INPUT CONFIGURATION Each input connection from the external capacitance sensors to the converter of the AD7147 can be uniquely configured by using the registers in Bank 2 (see Table 38). These registers are used to configure the input ...
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AD7147 NONCONTACT PROXIMITY DETECTION The AD7147 internal signal processing continuously monitors all capacitance sensors for noncontact proximity detection. This feature provides the ability to detect when a user is approaching a sensor, at which time all internal calibration is immediately ...
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Table 12. Proximity Control Registers (See Figure 34) Length Bit Name (Bits) FP_PROXIMITY_CNT 4 LP_PROXIMITY_CNT 4 FP_PROXIMITY_RECAL 8 LP_PROXIMITY_RECAL 6 PROXIMITY_RECAL_LVL 8 PROXIMITY_DETECTION_RATE 6 USER APPROACHES SENSOR CDC CONVERSION ...
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AD7147 USER APPROACHES SENSOR USER LEAVES SENSOR AREA CDC CONVERSION SEQUENCE (INTERNAL) PROXIMITY DETECTION (INTERNAL) CALIBRATION CALIBRATION DISABLED (INTERNAL) RECALIBRATION COUNTER (INTERNAL) NOTES 1. SEQUENCE CONVERSION TIME × FP_PROXIMITY_CNT × 16. CALDIS CONV_FP ...
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FF_SKIP_CNT The proximity detection fast FIFO is used by the on-chip logic to determine if proximity is detected. The fast FIFO expects to receive samples from the converter at a set rate. FF_SKIP_CNT is used to normalize the frequency of ...
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AD7147 16 CDC STAGEx_FF_WORD0 STAGEx_FF_WORD1 STAGEx_FF_WORD2 STAGEx_FF_WORD3 STAGEx_FF_WORD4 STAGEx_FF_WORD5 STAGEx_FF_WORD6 STAGEx_FF_WORD7 BANK 3 REGISTERS 7 Σ WORD( PROXIMITY SLOW_FILTER_EN COMPARATOR 3 STAGEx_SF_WORD0 WORD0 – CDC VALUE STAGEx_SF_WORD1 STAGEx_SF_WORD2 STAGEx_SF_WORD3 SLOW_FILTER_UPDATE_LVL STAGEx_SF_WORD4 REGISTER 0x003 STAGEx_SF_WORD5 STAGEx_SF_WORD6 STAGEx_SF_WORD7 ...
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ENVIRONMENTAL CALIBRATION The AD7147 provides on-chip capacitance sensor calibration to automatically adjust for environmental conditions that have an effect on the ambient levels of the capacitance sensor. The output levels of the capacitance sensor are sensitive to temperature, humidity, and, ...
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AD7147 THRESHOLD EQUATIONS On-Chip Logic Stage High Threshold = STAGEx _ HIGH _ THRESHOLD STAGEx ⎛ ⎛ STAGEx ⎜ − ⎜ STAGEx _ OFFSET _ HIGH ⎝ ⎜ ⎜ 16 ⎜ ⎝ On-Chip Logic Stage Low Threshold = STAGEx _ ...
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SLOW_FILTER_UPDATE_LVL The SLOW_FILTER_UPDATE_LVL controls whether the most recent CDC measurement goes into the slow FIFO (slow filter). The slow filter is updated when the difference between the current CDC value and the last value of the slow FIFO is greater ...
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AD7147 ADAPTIVE THRESHOLD AND SENSITIVITY The AD7147 provides an on-chip, self-adjusting adaptive threshold and sensitivity algorithm. This algorithm continu- ously monitors the output levels of each sensor and automatically rescales the threshold levels in proportion to the sensor area covered ...
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CDC Figure 39. Tracking the Minimum and Maximum Average Sensor Values Table 14. Additional Information About Environmental Calibration and Adaptive Threshold Registers Register Register/Bit Location NEG_THRESHOLD_SENSITIVITY Bank 2 NEG_PEAK_DETECT Bank 2 POS_THRESHOLD_SENSITIVITY Bank 2 POS_PEAK_DETECT Bank 2 ...
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AD7147 INTERRUPT OUTPUT The AD7147 has an interrupt output that triggers an interrupt service routine on the host processor. The INT signal is on Pin 17 and is an open-drain output. There are three types of interrupt events on the ...
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STAGE0 STAGE1 STAGE2 CONVERSIONS INT 1 SERIAL READS NOTES THIS IS AN EXAMPLE OF A CDC CONVERSION-COMPLETE INTERRUPT. THIS TIMING EXAMPLE SHOWS THAT THE INTERRUPT OUTPUT HAS BEEN ENABLED TO BE ASSERTED AT THE END OF A CONVERSION CYCLE FOR ...
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AD7147 GPIO INT OUTPUT CONTROL The INT output signal can be controlled by the GPIO pin when the GPIO is configured as an input. The GPIO is con-figured as an input by setting the GPIO_SETUP bits in the interrupt con- ...
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SERIAL READBACK GPIO INPUT LOW WHEN REGISTER IS READ BACK GPIO INPUT INT OUTPUT GPIO INPUT HIGH WHEN REGISTER IS READ BACK GPIO INPUT INT OUTPUT 1 READ GPIO_INT_STATUS BIT TO RESET INT OUTPUT. Figure 45. Example of INT Output ...
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AD7147 OUTPUTS AC OUTPUT SHIELD The AD7147 measures capacitance between CINx and ground. Any capacitance to ground on the signal path between the CINx pins and the sensor is included in the AD7147 conversion result. To eliminate stray capacitance to ...
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SERIAL INTERFACE The AD7147 is available with an SPI-compatible interface. The 2 AD7147-1 is available with an I C-compatible interface. Both parts are the same, with the exception of the serial interface. SPI INTERFACE The AD7147 has a 4-wire serial ...
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AD7147 16-BIT COMMAND WORD ENABLE WORD R SDI SCLK NOTES 1. MULTIPLE SEQUENTIAL REGISTERS CAN BE ...
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COMMAND WORD ENABLE WORD R SDI SCLK SDO XXX XXX XXX XXX XXX XXX XXX XXX ...
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AD7147 START AD7147-1 DEVICE ADDRESS SDA DEV DEV DEV DEV DEV SCLK REGISTER DATA [D15:D8] D15 D14 ACK NOTES 1. A START ...
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START AD7147-1 DEVICE ADDRESS SDA DEV DEV DEV DEV DEV SCLK AD7147-1 DEVICE ADDRESS SR DEV DEV A6 A5 USING REPEATED START ...
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AD7147 PCB DESIGN GUIDELINES CAPACITIVE SENSOR BOARD MECHANICAL SPECIFICATIONS Table 19. Parameter Distance from Edge of Any Sensor to Edge of Grounded Metal Object 1 Distance Between Sensor Edges Distance Between Bottom of Sensor Board and Controller Board or Grounded ...
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POWER-UP SEQUENCE To power up the AD7147, use the following sequence when initially developing the AD7147 and microprocessor serial interface: 1. Turn on the power supplies to the AD7147. 2. Write to the Bank 2 registers at Address 0x080 through ...
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AD7147 TYPICAL APPLICATION CIRCUITS BUTTON SCROLL WHEEL BUTTON PLANE AROUND SENSORS CONNECTED TO AC BUTTON BUTTON BUTTON 2-WAY SWITCH 1 CIN6 BUTTON 2 CIN7 3 CIN8 AD7147 4 CIN9 5 CIN10 6 CIN11 BUTTON SENSOR PCB 100nF 0.1μF SHIELD Figure ...
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REGISTER MAP The AD7147 address space is divided into three register banks, referred to as Bank 1, Bank 2, and Bank 3. Figure 62 illustrates the division of these banks. Bank 1 registers contain control registers, CDC conversion control registers, ...
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AD7147 DETAILED REGISTER DESCRIPTIONS BANK 1 REGISTERS All addresses and default values are expressed in hexadecimal. Table 20. PWR_CONTROL Register Default Address Data Bit Value 0x000 [1:0] 0 [3:2] 0 [7:4] 0 [9:8] 0 [10] 0 [11] 0 [12] 0 ...
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Table 21. STAGE_CAL_EN Register Default Address Data Bit Value Type 0x001 [0] 0 R/W [1] 0 R/W [2] 0 R/W [3] 0 R/W [4] 0 R/W [5] 0 R/W [6] 0 R/W [7] 0 R/W [8] 0 R/W [9] 0 ...
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AD7147 Table 22. AMB_COMP_CTRL0 Register Default Address Data Bit Value Type 0x002 [3:0] 0 R/W [7:4] F R/W [11:8] F R/W [13:12] 0 R/W [14] 0 R/W [15] 0 R/W Table 23. AMB_COMP_CTRL1 Register Default Address Data Bit Value Type ...
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Table 25. STAGE_LOW_INT_ENABLE Register Default Address Data Bit Value Type 0x005 [0] 0 R/W [1] 0 R/W [2] 0 R/W [3] 0 R/W [4] 0 R/W [5] 0 R/W [6] 0 R/W [7] 0 R/W [8] 0 R/W [9] 0 ...
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AD7147 Table 26. STAGE_HIGH_INT_ENABLE Register Default Address Data Bit Value Type 0x006 [0] 0 R/W [1] 0 R/W [2] 0 R/W [3] 0 R/W [4] 0 R/W [5] 0 R/W [6] 0 R/W [7] 0 R/W [8] 0 R/W [9] ...
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Table 27. STAGE_COMPLETE_INT_ENABLE Register Default Address Data Bit Value Type 0x007 [0] 0 R/W [1] 0 R/W [2] 0 R/W [3] 0 R/W [4] 0 R/W [5] 0 R/W [6] 0 R/W [7] 0 R/W [8] 0 R/W [9] 0 ...
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AD7147 Table 28. STAGE_LOW_INT_STATUS Register Default Address Data Bit Value Type 0x008 [ [ [ [ [ [ [ [ [ [9] ...
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Table 29. STAGE_HIGH_INT_STATUS Register Default Address Data Bit Value Type 0x009 [ [ [ [ [ [ [ [ [ [9] 0 ...
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AD7147 Table 30. STAGE_COMPLETE_INT_STATUS Register Default Address Data Bit Value Type 0x00A [ [ [ [ [ [ [ [ [ [9] ...
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Table 32. Device ID Register Default Address Data Bit Value Type 0x017 [3: [15:4] 147 R Table 33. Proximity Status Register Default Value Address Data Bit Type 0x042 [ [ [ [3] ...
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AD7147 BANK 2 REGISTERS All address values are expressed in hexadecimal. Table 34. STAGEx_CONNECTION[6:0] Register Description ( 11) Default Data Bit Value Type Name [1:0] X R/W CIN0_CONNECTION_SETUP [3:2] X R/W CIN1_CONNECTION_SETUP [5:4] X R/W CIN2_CONNECTION_SETUP [7:6] ...
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Table 35. STAGEx_CONNECTION[12:7] Register Description ( 11) Default Data Bit Value Type Name [1:0] X R/W CIN7_CONNECTION_SETUP [3:2] X R/W CIN8_CONNECTION_SETUP [5:4] X R/W CIN9_CONNECTION_SETUP [7:6] X R/W CIN10_CONNECTION_SETUP [9:8] X R/W CIN11_CONNECTION_SETUP [11:10] X R/W CIN12_CONNECTION_SETUP ...
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AD7147 Table 36. STAGEx_AFE_OFFSET Register Description ( 11) Default Data Bit Value Type Name [5:0] X R/W NEG_AFE_OFFSET [6] X Unused [7] X R/W NEG_AFE_OFFSET_SWAP [13:8] X R/W POS_AFE_OFFSET [14] X Unused [15] X R/W POS_AFE_OFFSET_SWAP Table ...
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Table 38. STAGE0 to STAGE11 Configuration Registers Address Data Bit Default Type 0x080 [15:0] X R/W 0x081 [15:0] X R/W 0x082 [15:0] X R/W 0x083 [15:0] X R/W 0x084 [15:0] X R/W 0x085 [15:0] X R/W 0x086 [15:0] X R/W ...
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AD7147 Address Data Bit Default Type 0x0B0 [15:0] X R/W 0x0B1 [15:0] X R/W 0x0B2 [15:0] X R/W 0x0B3 [15:0] X R/W 0x0B4 [15:0] X R/W 0x0B5 [15:0] X R/W 0x0B6 [15:0] X R/W 0x0B7 [15:0] X R/W 0x0B8 [15:0] ...
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BANK 3 REGISTERS All address values are expressed in hexadecimal. Table 39. STAGE0 Results Registers Default Address Data Bit Value Type 0x0E0 [15:0] X R/W 0x0E1 [15:0] X R/W 0x0E2 [15:0] X R/W 0x0E3 [15:0] X R/W 0x0E4 [15:0] X ...
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AD7147 Table 40. STAGE1 Results Registers Default Address Data Bit Value Type 0x104 [15:0] X R/W 0x105 [15:0] X R/W 0x106 [15:0] X R/W 0x107 [15:0] X R/W 0x108 [15:0] X R/W 0x109 [15:0] X R/W 0x10A [15:0] X R/W ...
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Table 41. STAGE2 Results Registers Default Address Data Bit Value Type 0x128 [15:0] X R/W 0x129 [15:0] X R/W 0x12A [15:0] X R/W 0x12B [15:0] X R/W 0x12C [15:0] X R/W 0x12D [15:0] X R/W 0x12E [15:0] X R/W 0x12F ...
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AD7147 Table 42. STAGE3 Results Registers Default Address Data Bit Value Type 0x14C [15:0] X R/W 0x14D [15:0] X R/W 0x14E [15:0] X R/W 0x14F [15:0] X R/W 0x150 [15:0] X R/W 0x151 [15:0] X R/W 0x152 [15:0] X R/W ...
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Table 43. STAGE4 Results Registers Default Address Data Bit Value Type 0x170 [15:0] X R/W 0x171 [15:0] X R/W 0x172 [15:0] X R/W 0x173 [15:0] X R/W 0x174 [15:0] X R/W 0x175 [15:0] X R/W 0x176 [15:0] X R/W 0x177 ...
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AD7147 Table 44. STAGE5 Results Registers Default Address Data Bit Value Type 0x194 [15:0] X R/W 0x195 [15:0] X R/W 0x196 [15:0] X R/W 0x197 [15:0] X R/W 0x198 [15:0] X R/W 0x199 [15:0] X R/W 0x19A [15:0] X R/W ...
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Table 45. STAGE6 Results Registers Default Address Data Bit Value Type 0x1B8 [15:0] X R/W 0x1B9 [15:0] X R/W 0x1BA [15:0] X R/W 0x1BB [15:0] X R/W 0x1BC [15:0] X R/W 0x1BD [15:0] X R/W 0x1BE [15:0] X R/W 0x1BF ...
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AD7147 Table 46. STAGE7 Results Registers Default Address Data Bit Value Type 0x1DC [15:0] X R/W 0x1DD [15:0] X R/W 0x1DE [15:0] X R/W 0x1DF [15:0] X R/W 0x1E0 [15:0] X R/W 0x1E1 [15:0] X R/W 0x1E2 [15:0] X R/W ...
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Table 47. STAGE8 Results Registers Default Address Data Bit Value Type 0x200 [15:0] X R/W 0x201 [15:0] X R/W 0x202 [15:0] X R/W 0x203 [15:0] X R/W 0x204 [15:0] X R/W 0x205 [15:0] X R/W 0x206 [15:0] X R/W 0x207 ...
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AD7147 Table 48. STAGE9 Results Registers Default Address Data Bit Value Type 0x224 [15:0] X R/W 0x225 [15:0] X R/W 0x226 [15:0] X R/W 0x227 [15:0] X R/W 0x228 [15:0] X R/W 0x229 [15:0] X R/W 0x22A [15:0] X R/W ...
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Table 49. STAGE10 Results Registers Default Address Data Bit Value Type 0x248 [15:0] X R/W 0x249 [15:0] X R/W 0x24A [15:0] X R/W 0x24B [15:0] X R/W 0x24C [15:0] X R/W 0x24D [15:0] X R/W 0x24E [15:0] X R/W 0x24F ...
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AD7147 Table 50. STAGE11 Results Registers Default Address Data Bit Value Type 0x26C [15:0] X R/W 0x26D [15:0] X R/W 0x26E [15:0] X R/W 0x26F [15:0] X R/W 0x270 [15:0] X R/W 0x271 [15:0] X R/W 0x272 [15:0] X R/W ...
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... AD7147PACPZ-RL –40°C to +85°C 1 AD7147PACPZ-500R7 –40°C to +85°C 1 AD7147ACPZ-1REEL –40°C to +85°C 1 AD7147ACPZ-1500RL7 –40°C to +85°C AD7147PACPZ-1RL 1 –40°C to +85°C 1 AD7147PACPZ-1500R7 –40°C to +85°C 1 EVAL-AD7147EBZ 1 EVAL-AD7147-1EBZ RoHS Compliant Part. 0.60 MAX 4 ...
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AD7147 NOTES Rev Page ...
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NOTES Rev Page AD7147 ...
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AD7147 NOTES ©2007–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06663-0-7/09(B) Rev Page ...