AD7147AACBZ-RL Analog Devices Inc, AD7147AACBZ-RL Datasheet - Page 2

• Manufacturer Part Number: AD7147AACBZ-RL
• Description: CAPACITANCE TO DIGITAL CONVERTER
• Manufacturer: Analog Devices Inc
• Series: CapTouch™r
• Type: Capacitive Sensor Controllerr

Specifications of AD7147AACBZ-RL

• Resolution (bits): 16 b
• Data Interface: Serial, SPI™
• Voltage Supply Source: Single Supply
• Voltage - Supply: 2.6 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 25-WLCSP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Sampling Rate (per Second): -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AD7147A
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 7
Pin Configurations and Function Descriptions ........................... 8
Typical Performance Characteristics ............................................. 9
Theory of Operation ...................................................................... 11
Capacitance-to-Digital Converter ................................................ 14
Capacitance Sensor Input Configuration .................................... 17
Noncontact Proximity Detection ................................................. 18
Environmental Calibration ........................................................... 23
REVISION HISTORY
12/09—Rev. A to Rev. B
Changes to Figure 1 .......................................................................... 1
Changes to Figure 5, Figure 6, and Pin Description for B2 ........ 8
Changes to Figure 59 and Figure 60 ............................................. 39
Changes to Ordering Guide .......................................................... 68
Average Current Specifications .................................................. 4
SPI Timing Specifications (AD7147A) ...................................... 5
I
ESD Caution .................................................................................. 7
Capacitance Sensing Theory ..................................................... 11
BIAS Pin ....................................................................................... 12
Operating Modes ........................................................................ 12
Oversampling the CDC Output ............................................... 14
Capacitance Sensor Offset Control .......................................... 14
Conversion Sequencer ............................................................... 14
CDC Conversion Sequence Time ............................................ 16
CDC Conversion Results ........................................................... 16
CINx Input Multiplexer Setup .................................................. 17
Single-Ended Connections to the CDC .................................. 17
Recalibration ............................................................................... 18
Proximity Sensitivity .................................................................. 18
FF_SKIP_CNT ............................................................................ 21
2
C Timing Specifications (AD7147A-1) .................................. 6
Rev. B | Page 2 of 68
Adaptive Threshold and Sensitivity ............................................. 25
Interrupt Output ............................................................................. 27
Outputs ............................................................................................ 31
Serial Interfaces ............................................................................... 32
PCB Design Guidelines ................................................................. 37
Power-Up Sequence ....................................................................... 38
Typical Application Circuits ......................................................... 39
Register Map ................................................................................... 40
Detailed Register Descriptions ..................................................... 41
Outline Dimensions ....................................................................... 68
3/09—Rev. 0 to Rev. A
Changes to Ordering Guide .......................................................... 68
1/09—Revision 0: Initial Version
Capacitance Sensor Behavior Without Calibration ............... 23
Threshold Equations .................................................................. 23
Capacitance Sensor Behavior with Calibration ...................... 24
Slow FIFO .................................................................................... 24
SLOW_FILTER_UPDATE_LVL .............................................. 24
CDC Conversion-Complete Interrupt .................................... 27
Sensor-Touch Interrupt ............................................................. 27
GPIO INT Output Control ....................................................... 29
AC
General-Purpose Input/Output (GPIO) ................................. 31
Using the GPIO to Turn On/Off an LED ................................ 31
SPI Interface ................................................................................ 32
I
V
Capacitive Sensor Board Mechanical Specifications ............. 37
WLCSP Package ......................................................................... 37
Bank 1 Registers ......................................................................... 41
Bank 2 Registers ......................................................................... 51
Bank 3 Registers ......................................................................... 56
Ordering Guide .......................................................................... 68
2
C-Compatible Interface .......................................................... 34
DRIVE
SHIELD
Input ................................................................................. 36
Output .......................................................................... 31