MLX92241LSE-AAA-008 Datasheet, PDF (8/11 Pages) Melexis Microelectronic Systems – 2-Wire Hall Effect Switch

MLX92241LSE-AAA-008
2-Wire Hall Effect Switch
8 Application Information
8.1 Typical Automotive Application Circuit
ECU
V_CC
C1
10nF
VH_SENSE
R_SENSE
100
MLX92221
VDD
TEST
GND
Notes:
1. For proper operation, a 10nF bypass capacitor should be placed
as close as possible to the V_DD and ground(GND) pin. For complete
emissions protection a C1 = 68nF is recommended.
2. The TEST pin is to be left open or connected to GND.
8.2 Automotive and Harsh, Noisy
Environments Application Circuit
ECU
D1
(optiona,l
C1
MLX92221
VCC
see Note2)
68nF
VDD
DZ1
TEST
VHSENSE
(optiona,l
see Note3)
GND
RSENSE
100
Notes:
1. For proper operation , a 10nF to 100nF bypass capacitor should be placed as close
as possible to the V_DD and ground pin.
2. The device could tolerate negative voltage down to -24V, so if negative transients
over supply line VPEAK< -29V are expected, usage of the diode D1 is recommended .
Otherwise only RSENSEis sufficient .
When selecting the resistor RSENSE, three points are important:
- the resistor has to limit I_DD/I_DDREV to 50mA maximum
- the resistor has to withstand the power dissipated in both over voltage
conditions (V_RSENSE2/R_SENSE)
- the resulting device supply voltage V _DD has to be higher than V _DDmin
(VDD = VCC – RSENSE.IDD)
3. The device could tolerate positive supply voltage up to +27V (until the maximum
power dissipation is not exceeded), so if positive transients over supply line with
V_PEAK> 32V are expected, usage a zener diode DZ 1 is recommended . The R_SENSE-DZ1
network should be sized to limit the voltage over the device below the maximum
allowed.
8.3 Strobbing VDD application (used for
reduced self-heating)
ECU
VCC
VHSENSE
RSENSE
100
C1
68nF
MLX92221
VDD
TEST
GND
VDD
12 V
South Pole
weak South or B = null
ON phase
I DD
(1ms)
OFF phase
(1s)
t
I _ONtyp
I _OFFtyp
t ON
Valid IDD
state
Valid IDD
state
t ON
t
Notes :
1. Given strobe timing is exemplary only. The output response is for sensor type
MLX92221xxx-xLxS.
2. For proper operation, a 10nF to 100nF bypass capacitor should be placed as
close as possible to the V_DD and ground pin.
390109224108 Rev. 1
Page 8 of 11
March/12