ams Datasheet Page 9
[v2-06] 2014-Oct-14 Document Feedback
AS5055A − Detailed Description
Typical Application
The AS5055A uses on-chip Hall elements to convert the
magnetic field component perpendicular to the surface of the
chip into a voltage.
The signals from the Hall elements are amplified and filtered by
the analog front-end (AFE) before being converted by the
analog-to-digital converter (ADC). The output of the ADC is
processed by the hardwired CORDIC (coordinate rotating
digital computer) block to compute the angle and magnitude
of the magnetic vector. The intensity of the magnetic field
(magnitude) is used by the automatic gain control (AGC) to
adjust the amplification level for compensation of temperature
and magnetic field variations.
The internal 12-bit resolution is available by reading a register
through the SPI interface. The IC settings in the AS5055A can
be programmed through the SPI interface without any
dedicated programmer.
Figure 10:
Typical Application Using SPI 4-Wire Mode and INT/ Output
Figure 10 shows how the AS5055A can be connected to a
microcontroller. The SPI interface is a slave interface for
accessing the on-chip registers. The INT/ output is an active-low
interrupt for informing the host microcontroller when a new
result is available.
ADC
AS5055A
VDD
VSS
SS/
MOSI
SCK
MISO
Analog
Front-End
ATAN
(CORDIC)
AGC
INT/
EN_INT/
Hall Sensors
Low Power Management
VDDp WM
SPI
Test
µC
4.7µF 15 R
DC 3.0V – 3.6V
DC 1.8V – 3.6V
SPI
Interface
Interrupt
100nF
