AD7147 datasheet(29/73 Pages) AD

29 / 73 page

AD7147

Data Sheet

Rev. D | Page 28 of 72

BANK 3 REGISTERS

STAGEx_MAX_WORD0

STAGEx_MAX_WORD1

STAGEx_MAX_WORD2

STAGEx_MAX_WORD3

STAGEx_MIN_WORD0

STAGEx_MIN_WORD1

STAGEx_MIN_WORD2

STAGEx_MIN_WORD3

STAGEx_MAX_AVG

BANK 3 REGISTERS

STAGEx_MAX_TEMP

BANK 3 REGISTERS

STAGEx_HIGH_THRESHOLD

BANK 3 REGISTERS

STAGEx_MIN_AVG

BANK 3 REGISTERS

STAGEx_MIN_TEMP

BANK 3 REGISTERS

STAGEx_LOW_THRESHOLD

BANK 3 REGISTERS

MAXIMUM

LEVEL

DETECTION

LOGIC

MINIMUM

LEVEL

DETECTION

LOGIC

Σ-∆

16-BIT

CDC

Figure 39. Tracking the Minimum and Maximum Average Sensor Values

Table 14. Additional Information About Environmental Calibration and Adaptive Threshold Registers

Location

Description

NEG_THRESHOLD_SENSITIVITY

Bank 2

Used in Equation 2. This value is programmed once at startup.

NEG_PEAK_DETECT

Bank 2

Used by internal adaptive threshold logic only.

The NEG_PEAK_DETECT is set to a percentage of the difference between the ambient

CDC value and the minimum average CDC value. If the output of the CDC approaches the

NEG_PEAK_DETECT percentage of the minimum average, the minimum average value is updated.

POS_THRESHOLD_SENSITIVITY

Bank 2

Used in Equation 1. This value is programmed once at startup.

POS_PEAK_DETECT

Bank 2

Used by internal adaptive threshold logic only.

The POS_PEAK_DETECT is set to a percentage of the difference between the ambient

CDC value and the maximum average CDC value. If the output of the CDC approaches the

POS_PEAK_DETECT percentage of the maximum average, the maximum average value is updated.

STAGEx_OFFSET_LOW

Bank 2

Used in Equation 2. An initial value (based on sensor characterization) is programmed into

this register at startup. The AD7147 on-chip calibration algorithm automatically updates this

STAGEx_OFFSET_HIGH

Bank 2

Used in Equation 1. An initial value (based on sensor characterization) is programmed into

this register at startup. The AD7147 on-chip calibration algorithm automatically updates this

STAGEx_OFFSET_HIGH_CLAMP

Bank 2

Used by internal environmental calibration and adaptive threshold algorithms only.

An initial value (based on sensor characterization) is programmed into this register at startup.

The value in this register prevents a user from causing the output value of a sensor to exceed

the expected nominal value.

Set this register to the maximum expected sensor response or the maximum change in CDC

output code.

STAGEx_OFFSET_LOW_CLAMP

Bank 2

Used by internal environmental calibration and adaptive threshold algorithms only.

An initial value (based on sensor characterization) is programmed into this register at startup.

The value in this register prevents a user from causing the output value of a sensor to exceed

the expected nominal value.

Set this register to the minimum expected sensor response or the minimum change in CDC

output code.

STAGEx_SF_AMBIENT

Bank 3

Used in Equation 1 and Equation 2. This is the ambient sensor output when the sensor is not

touched, as calculated using the slow FIFO.

STAGEx_HIGH_THRESHOLD

Bank 3

Equation 1 value.

STAGEx_LOW_THRESHOLD

Bank 3

Equation 2 value.

AD7147 Datasheet(PDF) 29 Page - Analog Devices

AD7147 Datasheet(HTML) 29 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73

Datasheet Download

Link URL