AD7147A Analog Devices, AD7147A Datasheet - Page 22

• Manufacturer Part Number: AD7147A
• Manufacturer: Analog Devices

Specifications of AD7147A

• Resolution (bits): 16bit
• # Chan: 13
• Sample Rate: 111SPS
• Interface: I²C/Ser 2-Wire,Ser,SPI
• Analog Input Type: Capacitive
• Ain Range: ± 8 pF (Delta C)
• Adc Architecture: Sigma-Delta
• Pkg Type: CSP

AD7147A
SLOW_FILTER_UPDATE_LVL
SLOW_FILTER_EN
|WORD0 – CDC VALUE|
NOTES
1. SLOW_FILTER_EN, WHICH IS THE NAME OF THE OUTPUT OF COMPARATOR 3, IS SET AND SW1 IS CLOSED WHEN |STAGEx_SF_ WORD0 – CDC VALUE |
2. PROXIMITY 1 IS SET WHEN |STAGEx_FF_ WORD0 – STAGEx_FF_WORD3 | EXCEEDS THE VALUE PROGRAMMED IN THE
3. PROXIMITY 2 IS SET WHEN | AVERAGE – AMBIENT | EXCEEDS THE VALUE PROGRAMMED IN THE PROXIMITY_RECAL_LVL REGISTER.
4. DESCRIPTION OF COMPARATOR FUNCTIONS:
COMPARATOR 3
REGISTER 0x003
EXCEEDS THE VALUE PROGRAMMED IN THE SLOW_FILTER_UPDATE_LVL REGISTER PROVIDING PROXIMITY IS NOT SET.
PROXIMITY_DETECTION_RATE REGISTER.
COMPARATOR 1: USED TO DETECT WHEN A USER IS APPROACHING OR LEAVING A SENSOR.
COMPARATOR 2: USED TO DETECT WHEN A USER IS HOVERING OVER A SENSOR OR APPROACHING A SENSOR VERY SLOWLY.
COMPARATOR 3: USED TO ENABLE THE SLOW FILTER UPDATE RATE. THE SLOW FILTER IS UPDATED WHEN SLOW_FILTER_EN IS SET AND
PROXIMITY
ALSO USED TO DETECT IF THE SENSOR AMBIENT LEVEL HAS CHANGED AS A RESULT OF THE USER INTERACTION.
FOR EXAMPLE, HUMIDITY OR DIRT LEFT BEHIND ON SENSOR.
PROXIMITY IS NOT SET.
CDC
16
STAGEx_FF_WORD0
STAGEx_FF_WORD1
STAGEx_FF_WORD2
STAGEx_FF_WORD3
STAGEx_FF_WORD4
STAGEx_FF_WORD5
STAGEx_FF_WORD6
STAGEx_FF_WORD7
Σ
N = 0
7
WORD(N)
STAGEx_SF_WORD0
STAGEx_SF_WORD1
STAGEx_SF_WORD2
STAGEx_SF_WORD3
STAGEx_SF_WORD4
STAGEx_SF_WORD5
STAGEx_SF_WORD6
STAGEx_SF_WORD7
BANK 3 REGISTERS
8
BANK 3 REGISTERS
SW1
BANK 3 REGISTERS
STAGEx_FF_AVG
PROXIMITY_DETECTION_RATE
|WORD0 – WORD3|
REGISTER 0x003
STAGEx_SF_AMBIENT
COMPARATOR 1
Figure 33. Proximity-Detection Logic
BANK 3 REGISTERS
Rev. B | Page 22 of 68
PROXIMITY_RECAL_LVL
|AVERAGE – AMBIENT|
COMPARATOR 2
REGISTER 0x003
PROXIMITY 1
PROXIMITY
FP_PROXIMITY_RECAL
STAGEx_SF_WORDx
FP_PROXIMITY_CNT
STAGEx_FF_WORDx
REGISTER 0x002
REGISTER 0x004
PROXIMITY TIMING
CONTROL LOGIC
CONTACT
SENSOR
LP_PROXIMITY_RECAL
LP_PROXIMITY_CNT
REGISTER 0x002
REGISTER 0x004
AMBIENT
VALUE
t