AD7142 Analog Devices, AD7142 Datasheet - Page 27

• Manufacturer Part Number: AD7142
• Description: Programmable Controller for Capacitance Touch Sensors
• Manufacturer: Analog Devices

Specifications of AD7142

• Resolution (bits): 16bit
• # Chan: 14
• Sample Rate: 250kSPS
• Interface: I²C/Ser 2-Wire,Ser,SPI
• Analog Input Type: Diff-Uni
• Ain Range: ± 2 pF (Delta C)
• Adc Architecture: Sigma-Delta
• Pkg Type: CSP

CONVERSIONS
CONVERSIONS
SERIAL
READS
SERIAL
READS
INT
INT
NOTES
THIS IS AN EXAMPLE OF A SENSOR THRESHOLD INTERRUPT FOR A CASE WHERE THE LOW THRESHOLD LEVELS WERE EXCEEDED.
FOR EXAMPLE: THE SENSOR CONNECTED TO STAGE0 AND STAGE9 WERE CONTACTED AND THE LOW THRESHOLD LEVELS WERE EXCEEDED RESULTING
IN THE INTERRUPT BEING ASSERTED. THE STAGE6 INTERRUPT WAS NOT ASSERTED BECAUSE THE USER DID NOT CONTACT THE SENSOR CONNECTED TO
STAGE6.
STAGEx CONFIGURATION PROGRAMMING NOTES FOR STAGE0, STAGE6, AND STAGE9 (x = 0, 6, 9)
STAGEx_LOW_INT_EN (ADDRESS 0x005) = 1
STAGEx_HIGH_INT_EN (ADDRESS 0x006) = 0
STAGEx_COMPLETE_EN (ADDRESS 0x007) = 0
STAGEx CONFIGURATION PROGRAMMING NOTES FOR STAGE1 THROUGH STAGE7, STAGE8, STAGE10, AND STAGE11 (x = 1, 2, 3, 4, 5, 6, 7, 8, 10, 11)
STAGEx_LOW_INT_EN (ADDRESS 0x005) = 0
STAGEx_HIGH_INT_EN (ADDRESS 0x006) = 0
STAGEx_COMPLETE_EN (ADDRESS 0x007) = 0
SERIAL READBACK REQUIREMENTS FOR STAGE0 AND STAGE9. THIS READBACK OPERATION IS REQUIRED TO CLEAR THE INTERRUPT OUTPUT.
1. READ THE STAGE0_LOW_LIMIT_INT (ADDRESS 0x008) REGISTER
2. READ THE STAGE5_LOW_LIMIT_INT (ADDRESS 0x008) REGISTER
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
STAGE0, STAGE5, AND STAGE9. THE INTERRUPTS FOR ALL OTHER STAGES HAVE BEEN DISABLED.
STAGEx CONFIGURATION PROGRAMMING NOTES FOR STAGE0, STAGE5, AND STAGE9 (x = 0, 5, 9)
STAGEx_LOW_INT_EN (ADDRESS 0x005) = 0
STAGEx_HIGH_INT_EN (ADDRESS 0x006) = 0
STAGEx_COMPLETE_EN (ADDRESS 0x007) = 1
STAGEx CONFIGURATION PROGRAMMING NOTES FOR STAGE1 THROUGH STAGE8, STAGE10, AND STAGE11 (x = 1, 2, 3, 4, 5, 6, 7, 8, 10, 11)
STAGEx_LOW_INT_EN (ADDRESS 0x005) = 0
STAGEx_HIGH_INT_EN (ADDRESS 0x006) = 0
STAGEx_COMPLETE_EN (ADDRESS 0x007) = 0
SERIAL READBACK REQUIREMENTS FOR STAGE0, STAGE5 AND STAGE9. THIS READBACK OPERATION IS REQUIRED TO CLEAR THE INTERRUPT OUTPUT.
1. READ THE STAGE0_COMPLETE_STATUS_INT (ADDRESS 0x00A) REGISTER
2. READ THE STAGE5_COMPLETE_STATUS_INT (ADDRESS 0x00A) REGISTER
3. READ THE STAGE9_COMPLETE_STATUS_INT (ADDRESS 0x00A) REGISTER
STAGE0
STAGE0
1
1
STAGE1
STAGE1
Figure 39. Example of Configuring the Registers for End of Conversion Interrupt Setup
STAGE2
Figure 40. Example of Configuring the Registers for Sensor Interrupt Setup
STAGE2
STAGE3
STAGE3
STAGE4
STAGE4
Rev. A | Page 27 of 72
STAGE5
STAGE5
4
2
STAGE6
STAGE6
STAGE7
STAGE7
STAGE8
STAGE8
STAGE9
STAGE9
3
2
STAGE10
STAGE10
STAGE11
STAGE11
AD7142