Flyer MLX16305 DownloadLink 4975

Intelligent Drivers
and Actuators
Sensor Interface
The MLX16305 is designed to diagnose the state of
remote interlock switches in automotive safety
applications (40V Load-dump). Its high accuracy allows
it to be applied in a broad range of related automotive
and industrial applications using current modulated
sensors and switches.
The MLX16305 includes a current-limited regulated
supply that is applied to one channel (switch/sensor) at
a time. The supplied current or the resulting supply
voltage are measured and presented as an analog
voltage to the microcontroller for interpretation.
Multiple MLX16305 devices can
be applied in parallel to scan
6/12/18/... channels.
RF & RFID
MLX16305
Automotive ICs
Interlock Switch Sensor
Interface IC
Benefits
Silicon MEMS
BUS ICs
• Fail safe read out of multiple safety interlock switches
• Automotive Seat occupancy, Seat belt buckle, Airbag
presence detection
• Automotive Door lock position, Hood and Trunk latched
detection
• Industrial Security doors and machine guarding
• Industrial pressure, strain gauge, … 2 wire analog sensors
(ref. MLX90308, MLX90314)
CMOS Imaging
Applications
Hall ICs
• Benefits for Resistive
switches
The high current range
(up to 40mA) allows contact
cleaning. If, any contact aging
occurs, the high measurement accuracy
allows to track and even predict failures.
• Benefits for 2-wire Hall effect switches
The wide voltage and current range allows application of
the MLX16305 with any 2-wire Hall effect sensor, including
general purpose (3-wire) Hall effect switches like Melexis’
US5782 in a current biasing scheme.
• Benefits for 2-wire analog sensor
Industrial sensors and sensor interfaces having a 4 to 20
mA current range, like the MLX90308/90314, can be read
out sequentially.
Full Application schematic including resistive switch and general purpose hall switch
in a 2-wire scheme
78L05
RF & RFID
C1
10uF
MLX16305
1
Sense3
Sense4
16
2
Sense2
Sense5
15
3
Sense1
Sense6
14
4
VSUP
VSS
13
DIG1
5
ENABLE1
RREF
12
DIG2
6
MUX_SENSE1
MEAS_OUT
11
DIG3
7
MUX_SENSE2
VI_CTRL
10
DIG4
8
MUX_SENSE3
VREF
C2
47nF
Microcontroller
VDD
Rser
To Interlock Switches
Rpar
Automotive ICs
Application Schematics
R2
820Ω
R1
2.2kΩ
9
1
2
OUT
VDD
US5782
VSS
3
C3
10nF
DIG5
ADC1
An 18 switch application requires 1ADC input and 7 digital IO’s
Switches[1:6]
Switches[7:12]
Switches[13:18]
1
16
1
16
15
2
15
2
15
14
3
14
3
13
4
13
4
12
5
12
5
11
6
11
6
10
7
10
7
9
8
9
8
3
4
5
6
7
8
MLX16305
16
2
MLX16305
1
MLX16305
Sensor Interface
Intelligent Drivers
and Actuators
VSS
14
13
12
11
10
9
4
Hall ICs
IO1
IO[2..5]
ADC
IO6
IO7
Microcontroller
Silicon MEMS
CMOS Imaging
Application Example with 2 wire Hall Switch
This example shows the threshold voltages for a 2 wire Hall switch with currents IOFF=[5; 6.9]mA
and ION=[12; 17]mA. Vref is taken from the 5V microcontroller supply regulator and Rref is set to
1kW.
1.
2.
3.
4.
5.
6.
Short to Supply:
Short between Wires:
Open Wire :
Switch current: IOFF: 0.43V <
Switch current ION:
1.03V <
Short to GND :
VThreshold
VThreshold
VThreshold
VThreshold
VThreshold
VThreshold
>
>
<
<
<
>
0.2V
0.2V
0.02V
0.65V
1.61V
4.5V
Each value is applicable after setting the appropriate values on the digital IOs.
BUS ICs
Disclaimer:
Devices sold by Melexis are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. Melexis makes no warranty, express, statutory, implied, or by
description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. Melexis reserves the right to change specifications and
prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with Melexis for current information. This product is intended for use
in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical lifesupport or life-sustaining equipment are specifically not recommended without additional processing by Melexis for each application. The information furnished by Melexis is believed to be
correct and accurate. However, Melexis shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss
of use, interrupt of business or indirect, special incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical
data herein. No obligation or liability to recipient or any third party shall arise or flow out of Melexis’ rendering of technical or other services.
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