ADIS16305

Rev. 0 | Page 12 of 20

ORIENTATION ANGLES

The ROLL_OUT and PITCH_OUT registers provide a tilt

angle calculation based on the accelerometer measurements.

The zero reference is the point at which the z-axis faces gravity

for a north-east-down (NED) configuration. Table 12 displays

a number of examples for the 13-bit, twos complement digital

format in both of these registers. Figure 14 provides the physical

references and formulas that produce these orientation angles.

Table 12. Orientation Angles, Twos Complement Format

Angle

Decimal

Hex

Binary

+180°

+4091

0x0FFB

XXX0 1111 1111 1011

+90

+2045

0x07FD

XXX0 0111 1111 1101

+0.088°

+2 LSB

0x0002

XXX0 0000 0000 0010

+0.044°

+1 LSB

0x0001

XXX0 0000 0000 0001

0°

0 LSB

0x0000

XXX0 0000 0000 0000

−0.044°

−1

0x1FFF

XXX1 1111 1111 1111

−0.088°

−2

0x1FFE

XXX1 1111 1111 1110

−90°

−2045

0x1803

XXX1 1000 0000 0011

−179.96°

−4090

0x1006

XXX1 0000 0000 0110

FRONT VIEW

SIDE VIEW

Z-AXIS

Y-AXIS

Z-AXIS

X-AXIS

φ

ROLL

φ

PITCH

φ

φ

Figure 14. Orientation for PITCH_OUT and ROLL_OUT Angles

Power Supply

The SUPPLY_OUT register provides an internal measurement

for the power supply voltage and uses a 12-bit, offset binary

digital format. Table 13 provides several numerical examples

of this format.

Table 13. Power Supply, Offset Binary Format

Supply Voltage

Decimal

Hex

Binary

5.25 V

2171 LSB

0x87B

XXXX 1000 0111 1011

5.002418 V

2069 LSB

0x815

XXXX 1000 0001 0101

5 V

2068 LSB

0x814

XXXX 1000 0001 0100

4.997582 V

2067 LSB

0x813

XXXX 1000 0001 0011

4.75 V

1964 LSB

0x7AC

XXXX 0111 1010 1100

Internal Temperature

The TEMP_OUT register provides an internal measurement for

temperature and uses 12-bit, twos complement for its digital format.

Table 14 provides several numerical examples of this format.

This is an internal temperature measurement, which can vary

from ambient conditions outside of the package.

Table 14. Temperature, Twos Complement Format

Temperature

Decimal

Hex

Binary

+105°C

+588 LSB

0x24C

XXXX 0010 0100 1100

+85°C

+441 LSB

0x1B9

XXXX 0001 1011 1001

+25.272°C

+2 LSB

0x002

XXXX 0000 0000 0010

+25.136°C

+1 LSB

0x001

XXXX 0000 0000 0001

+25°C

0 LSB

0x000

XXXX 0000 0000 0000

+24.864°C

−1 LSB

0xFFF

XXXX 1111 1111 1111

+24.728°C

−2 LSB

0xFFE

XXXX 1111 1111 1110

−40°C

−478 LSB

0xE22

XXXX 1110 0010 0010

Analog Input (ADC)

The AUX_ADC register provides access to the auxiliary ADC

input channel measurements and uses 12-bit, offset binary as its

digital format. The ADC is a 12-bit successive approximation

converter that has an input circuit equivalent to the one shown

in Figure 15. The maximum input is 3.3 V. The ESD protection

diodes can handle 10 mA without causing irreversible damage.

The on resistance (R1) of the switch has a typical value of 100 Ω.

The sampling capacitor, C2, has a typical value of 16 pF.

C2

C1

R1

VCC

D

D

Figure 15. Equivalent Analog Input Circuit

(Conversion Phase: Switch Open,

Track Phase: Switch Closed)

Table 15. ADC Measurement, Offset Binary Format

Input Voltage

Decimal

Hex

Binary

3.3 V

4095 LSB

0xFFF

XXXX 1111 1111 1111

1 V

1241 LSB

0x4D9

XXXX 0100 1101 1001

1.6118 mV

2 LSB

0x002

XXXX 0000 0000 0010

805.9 μV

1 LSB

0x001

XXXX 0000 0000 0001

0 V

0 LSB

0x000

XXXX 0000 0000 0000