NSE-5310 Datasheet, PDF (14/21 Pages) ams AG – Miniature Position Encoder SOIC with Zero Reference and I²C Output

NSE-5310
Data Sheet - Application Information
8.5 Z-axis Range Indication (“Red/Yellow/Green” Indicator)
The NSE-5310 provides several options of detecting the magnet distance by indicating the strength of the magnetic field. Signal indicators
MagINCn and MagDECn are available both as hardware pins (pins 2 and 3) and as status bits in the serial data stream (see Figure 9).
Additionally the LIN status bit indicates the non-recommended “red” range.
The digital status bits MagINC, MagDec, LIN and the hardware pins MagINCn, MagDECn have the following function:
Table 11. Magnetic Field Strength Red-Yellow-Green Indicators
Status Bits
MAG
Hardware Pins
Mag Mag
INC DEC
Lin
M11…
M0
Mag Mag
INCn DECn
Description
No distance change
0
0
0
3F hex
OFF
OFF _{Magnetic input field OK (GREEN range, ~10-40mT peak amplitude)}
Distance increase; this state is a dynamic state and only active while the
0
1
0
3F hex OFF OFF magnet is moving away from the chip. Magnitude register may change
but regulates back to 3F hex.
Distance decrease; this state is a dynamic state and only active while the
1
0
0
3F hex OFF OFF magnet is moving towards the chip. Magnitude register may change but
regulates back to 3F hex.
YELLOW range: magnetic field is ~3.4-4.5mT.
1
1
0
20 hex - 5F
hex
ON
OFF The device may still be operated in this range, but with slightly reduced
accuracy.
RED range: magnetic field is <3.4mT (MAG <20) or >54.5mT
1
1
1
<20 hex
>5F hex
ON
ON (MAG >5F). It is still possible to operate the device in the red range, but
not recommended.
8.6 Pulse Width Modulation (PWM) Output
The NSE-5310 also provides a pulse width modulated output (PWM), whose duty cycle is proportional to the relative linear position of the
magnet within one pole pair (2.0 mm). This cycle repeats after every subsequent pole pair:
Position
=
-^t--^o---ⁿ---^â‹---4---0---9---8---
(t_on + t_off)
–
1
(EQ 1)
Where:
Digital position = 0 – 4094
Exception: A linear position of 1999.5µm = digital position 4095 will generate a pulse width of tON = 4097µs and a pause tOFF = 1µs
The PWM frequency is internally trimmed to an accuracy of ±5% (±10% over full temperature range). This tolerance can be cancelled by
measuring the complete duty cycle as shown above.
Operating Conditions: TAMB = -40 to +125ºC, VDD5V = 3.0~3.6V (3V operation) VDD5V = 4.5~5.5V (5V operation) unless otherwise noted.
Table 12. PWM Output Timing Considerations
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Signal period = 4098µs ±5% at
TAMB=25ºC
232
244
256
f_PWM
PWM frequency
Hz
= 4098µs ±10% at
TAMB= -40 to +125ºC
220
244
268
PW_MIN
PW_MAX
Minimum pulse width
Maximum pulse width
Position 0d = 0µm
0.9
1
1.1
µs
Position 4095d = 1999.5µm
3892 4097
4301
µs
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