HAL810 Datasheet, PDF (22/30 Pages) Micronas – Programmable Linear Hall-Effect Sensor

HAL 810
DATA SHEET
4. Application Notes
4.1. Application Circuit
For EMC protection, it is recommended to connect one
ceramic 4.7 nF capacitor each between ground and
the supply voltage, respectively the output pin. In addi-
tion, the input of the controller unit should be pulled-
down with a 10 kΩ resistor and a ceramic 4.7 nF
capacitor.
Please note that during programming, the sensor will
be supplied repeatedly with the programming voltage
of 12.5 V for 100 ms. All components connected to the
V_DD line at this time must be able to resist this voltage.
4.2. Measurement of a PWM Output Signal
The magnetic field information is coded in the duty
cycle of the PWM signal. The duty cycle is defined as
the ratio between the high time “s” and the period “d” of
the PWM signal (see Fig. 4–2).
Please note: The PWM signal is updated with the fall-
ing edge. If the duty cycle is evaluated with a micro-
controller, the trigger-level will be the falling edge of
the PWM signal.
V_DD
4.7 nF
HAL810
OUT
4.7 nF
4.7 nF
GND
μC
10 kΩ
Fig. 4–1: Recommended application circuit
Out
V_high
d
s
V_low
Update
Fig. 4–2: Definition of PWM signal
time
22
Feb. 6, 2009; DSH000034_003EN
Micronas