NSE-5310 Datasheet, PDF (12/21 Pages) ams AG – Miniature Position Encoder SOIC with Zero Reference and I²C Output

NSE-5310
Data Sheet - Application Information
8.2 Automatic Gain Control (AGC)
As the magnetic input field varies non-linearly with the air gap between sensor and magnet, the gain is controlled to an optimum input signal for
the SD ADC. The magnitude output is compared to a target register value. The most significant eight bits are used. If the actual magnitude differs
from the target value, an UP/DOWN signal for the AGC counter signal is generated.
For air gap detection functionality, two magnitude-change outputs are derived from the AGC counter UP/DOWN signals while the loop is
controlling the amplitude back to the target amplitude. Magnitude Increasing (MagINCn) and Magnitude Decreasing (MagDECn) signals indicate
air gap (SIN/COS amplitude) changes. Both signals are high for saturation of the AGC counter (running into upper / lower limit) and produce a
Non-Valid-Range alarm. The output pins can be connected together in wired-OR configuration to produce a single NVRn bit. For faster power-up
and response time, a successive approximation algorithm is implemented.
8.3 Temperature Sensor
The Temperature Sensor provides the junction temperature information over the serial interface.
Table 10. Temperature Sensor Characteristics
Parameter
Conditions
Min
Absolute Error Trimmed
See I²C User Interface on page 12
Conversion Rate
for continuous readout (1303 clock cycles between
conversion)
Temperature Range
specified temperature range
-30
Readout Range
design limit for temperature range
-50
Resolution
Temp [ºC] = output code [LSB] x 0.667 [ºC/LSB] -
75[ºC]
Clock Frequency
System clock (4 MHz) divided by 4
Typ
8
0.667
Max
Units
±10
ºC
767 sample/s
70
ºC
80
ºC
bit
ºC/LSB
1
MHz
8.4 I²C User Interface
The device is accessible via an I2C two-wire serial interface. The default address is A<6:0>1000000. A<5:1> can be defined by the OTP I2C
Address. A0 can be selected by pulling up pin 11 (default internal pull down). CSn must be low during I²C data transmission (not connected /
internal pull down).
Figure 9. I²C Read Out by an µC-Master
Type Identifier Address Read
SDA
1 A5 A4 A3 A2 A1 A0p R/
D11 D10 D9 D8 D7 D6 D5 D4
D3
D2
D1
D0
Offset
Comp
Finish
cordic
Over
Flow
Lin
Alarm
Mag
Incr
Decr
AGC7
SCL
1
S
91
ACK
Address
by Slave
Data Byte 1
91
ACK
Master
Data Byte 2
91
ACK Data
Master Byte 3
D11 - D0: Linear position
Offset Compensation Finished: “high” indicates a data valid.
CORDIC OverFlow: “high” indicates a DSP calculation overflow.
Linearity Alarm: “high” indicates the ADC input range exceeds ±625mV (=Filter OverFlow)
MagIncr / MagDecr “high” OR connection indicates changing magnitude and non-valid input range (see also pin 2 and 3)
In addition to the position data, magnitude and temperature sensor information can be read out as described in Automatic Gain Control (AGC) on
page 12 and Temperature Sensor on page 12.
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