AS5045 AB austriamicrosystems, AS5045 AB Datasheet - Page 20

• Manufacturer Part Number: AS5045 AB
• Description: BOARD ADAPTER AS5045
• Manufacturer: austriamicrosystems

Specifications of AS5045 AB

• Sensor Type: Magnetic, Rotary Position
• Sensing Range: 360°
• Interface: Serial
• Voltage - Supply: 9V
• Embedded: No
• Utilized Ic / Part: AS5045
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Sensitivity: -

AS5045
Data Sheet
Figure 12. OTP Programming Connection of AS5045 (shown with AS5045 demoboard)
11.4 Analog Readback Mode
Non-volatile programming (OTP) uses on-chip zener diodes, which become permanently low resistive when
subjected to a specified reverse current.
The quality of the programming process depends on the amount of current that is applied during the programming
process (up to 130mA). This current must be provided by an external voltage source. If this voltage source cannot
provide adequate power, the zener diodes may not be programmed properly.
In order to verify the quality of the programmed bit, an analog level can be read for each zener diode, giving an
indication whether this particular bit was properly programmed or not.
To put the AS5045 in Analog Readback Mode, a digital sequence must be applied to pins CSn, PROG and CLK as
shown in Figure 13. The digital level for this pin depends on the supply configuration (3.3V or 5V; see section 13
3V / 5V Operation).
The second rising edge on CSn (OutpEN) changes pin PROG to a digital output and the log. high signal at pin PROG
must be removed to avoid collision of outputs (grey area in Figure 13).
The following falling slope of CSn changes pin PROG to an analog output, providing a reference voltage V
, that
ref
must be saved as a reference for the calculation of the subsequent programmed and unprogrammed OTP bits.
Following this step, each rising slope of CLK outputs one bit of data in the reverse order as during programming
(see Figure 10: Md0-MD1-Div0,Div1-Indx-Z0…Z11, ccw).
If a capacitor is connected to pin PROG, it should be removed during analog readback mode to allow a fast readout
rate. If the capacitor is not removed the analog voltage will take longer to stabilize due to the additional capacitance.
The measured analog voltage for each bit must be subtracted from the previously measured V
, and the resulting
ref
value gives an indication on the quality of the programmed bit: a reading of <100mV indicates a properly
programmed bit and a reading of >1V indicates a properly unprogrammed bit.
A reading between 100mV and 1V indicates a faulty bit, which may result in an undefined digital value, when the
OTP is read at power-up.
th
Following the 18
clock (after reading bit “ccw”), the chip must be reset by disconnecting the power supply.
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