Melexis MLX16305 Interlock switch sensor interface ic Datasheet

MLX16305
Interlock switch sensor interface IC
Features and Benefits
6 sense Channels
Large supply current + supply voltage range for maximum contact cleaning
Applicable with all 2-wire Hall effect switches
Diagnoses open wires, shorts to Supplies and shorts between wires
o Current and Voltage measurement mode
o High measurement accuracy: 5%
Current limited supply regulator
Automotive qualified (40V Load Dump)
Over-temperature detection
Small Package: narrow body (150mils) SO16, RoHS compliant
Applications
General Fail safe read out of safety interlock switches to
o Detect human action
o Verify solenoid/motor actuation
Automotive applications
o Next to the Safety ECU: interlock switch sensor supply and sensor I/F
Seat belt buckle
Seat occupancy mat
Air bag presence detection
Seat position switch
Airbag disable switch
o Next to Smart Junction Box / Body Control Module: Contact monitoring
Foot Brake pressed detection
Park position of the automatic transmission
Door lock position
…
o Analog Mux
Resistive coded rotary encoder
Fuel run dry switch
Seat Heater switch
…
Industrial applications:
o Industrial Security doors and machine guarding
o General 2 wire analog sensors :
Industrial pressure, strain gauge, … sensors (ref. MLX90308,
MLX90314)
Ordering Code
Product Code Temperature Code
MLX16305
E
Package Code
DC
Legend:
Temperature Code:
Package Code:
Packing Form:
E for temperature -40°c to 85°c
DC for SOIC150Mil
RE for reel
Ordering example:
MLX16305EDC-CCA-000-RE
3901016305
Rev. 008
Page 1 of 29
Option Code
CCA-000
Packing Form Code
RE
Data Sheet
Jun/12
MLX16305
Interlock switch sensor interface IC
1. Overview application Schematic
VSUP
VBAT
Resistive Rotary Encoder
78L05
Renc
Renc
Renc
Renc
VDD
VBAT
MEAS_OUT
ADC
Switch to VBAT
VREF
Microcontroller
VSUP
Sense1
Sense2
ENABLE
VI_CTRL
Sense3
MLX16305
MUX_SENSE1
(Rs3)
(Rp2)
Switch to GND
Sense4
Sense5
MUX_SENSE2
(Rs2)
Sense6
Rs6
MUX_SENSE3
GND
GND
RREF
Rref
Seat
Occupant
Interlock Switches
Resistive and 2-wire Hall
2. Description
The MLX16305 is designed to diagnose the state of remote interlock switches in automotive safety
applications. 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.
Each MLX16305 allows scanning up to 6 switches for changes in switch state, and for any type of
short/open circuit failure mode. The range of switches can easily be extended by adding other
MLX16305 devices in parallel on the same microcontroller ADC input.
The high current and voltage range allow maximum contact cleaning energy for resistive switches. The
high accuracy allows monitoring of contact ageing and early failures detection.
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
TABLE OF CONTENTS
FEATURES AND BENEFITS ....................................................................................................................... 1
APPLICATIONS ............................................................................................................................................ 1
1.
OVERVIEW APPLICATION SCHEMATIC ......................................................................................... 1-2
2.
DESCRIPTION .................................................................................................................................... 2-2
3.
ABSOLUTE MAXIMUM RATINGS ....................................................................................................... 4
4.
MLX16305 ELECTRICAL SPECIFICATIONS ...................................................................................... 4
5.
PIN ASSIGNMENT ................................................................................................................................ 5
6.
BLOCK DIAGRAM ................................................................................................................................ 6
7.
GENERAL DESCRIPTION .................................................................................................................... 7
8.
PIN DESCRIPTION ................................................................................................................................ 7
8.1.
SUPPLY RANGE (VSUP) ................................................................................................................................ 7
8.2.
INPUT VOLTAGE REFERENCE (VREF)............................................................................................................ 7
8.3.
VOLTAGE REGULATION (SENSE) .................................................................................................................. 8
8.4.
OUTPUT VOLTAGE TO THE MICROCONTROLLER ADC (MEAS_OUT) ............................................................ 8
8.5.
DIGITAL INPUTS ............................................................................................................................................. 9
8.6.
ENCODER: INTERNAL DIGITAL SIGNALS ................................................................................................... 10
9.
VOLTAGE MODE (VM) ....................................................................................................................... 13
10. CURRENT MODE (CM) ....................................................................................................................... 14
10.1. CURRENT TO VOLTAGE CONVERSION PRINCIPLE .......................................................................................... 14
10.2. THE ACTUAL MEASUREMENT ....................................................................................................................... 14
10.3. HOW TO DO AN OFFSET CURRENT MEASUREMENT ........................................................................................ 15
10.4. MEASUREMENT ERRORS .............................................................................................................................. 16
11. HOW TO PREDICT THE SYSTEM OPERATING ZONE .................................................................... 17
11.1. VMEASOUT LIMITS ..................................................................................................................................... 17
11.2. ISENSE LIMITS ............................................................................................................................................. 17
12. OVERCURRENT LIMITATION ............................................................................................................ 18
13. OVERTEMPERATURE DETECTION .................................................................................................. 19
13.1. OVERTEMPERATURE CONSIDERATIONS ........................................................................................................ 20
14. DIAGNOSTICS .................................................................................................................................... 21
14.1. SHORTS ........................................................................................................................................................ 21
14.2. OPEN WIRE .................................................................................................................................................. 21
14.3. DIAGNOSTICS FLOW ..................................................................................................................................... 22
15. MULTIPLEXING THE ADC INPUT BY SETTING MEAS_OUT HIGH IMPEDANT............................ 23
16. APPLICATION NOTES ....................................................................................................................... 24
16.1. SYSTEM DEFINITION EXAMPLE WITH 2-WIRE HALL SWITCHES ..................................................................... 24
16.2. RESISTIVE SWITCHES ................................................................................................................................... 25
16.3. 2-WIRE ANALOG SENSORS ............................................................................................................................ 25
16.4. GROUND SHIFT ............................................................................................................................................ 26
17. STANDARD INFORMATION REGARDING MANUFACTURABILITY OF MELEXIS PRODUCTS
WITH DIFFERENT SOLDERING PROCESSES ........................................................................................ 27
18. ESD PRECAUTIONS ........................................................................................................................... 27
19. PACKAGE INFORMATION ................................................................................................................. 28
20. DISCLAIMER ....................................................................................................................................... 29
3901016305
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
3. Absolute Maximum Ratings
Supply Voltage, VSUP (overvoltage)
40V
Supply Voltage, VSUP (operating)
25V
Supply Current, IDD
6 mA
Output Current, SENSE
90 mA
Storage Temperature Range, TS
-40°C .. +150°C
ESD Sensitivity (AEC Q100 002)
1.5 kV
Exceeding the absolute maximum ratings may cause permanent damage. Exposure to absolutemaximum-rated conditions for extended periods may affect device reliability.
4. MLX16305 Electrical Specifications
o
o
DC Operating Parameters Tj = -40 C to 90 C, VSUP = 8V to 25V (unless otherwise specified)
Symbol
Parameter
Vsup
Supply
Isense
Sense output current
Conditions
Max
Unit
8
25
V
Vsup-Vref ≥ 2.5V, Vref < 6.8V
1
30
mA
Vsup-Vref ≥ 3.5V, Vref < 6.8V
1
40
mA
Vsup-Vref ≥ 8V, Vref < 8.25V
Vref
Analog input
Rref
Min
Nom
1
45
mA
3
8.25
V
1
kOhm
IDD
Current consumption
VCC=25V,
no channel selected
6
mA
IVref
Current consumption on Vref
Vref = 5V
No current limitation condition
0.5
mA
Digital inputs
VIL
VIH
Input low voltage
-0.3
Input high voltage
1.9
Input pull-down
30
VMEAS
Output voltage range
0.05
IMEAS
Current capability
300
VMEAS_DIS
Output voltage in VM with voltage
regulator disabled
ENABLE = 0, VI_CTRL=0
(VM)
Isense_pd
SENSE pin pull-down
2V< Vsense < 24V
Meas_Verr1
Error in Voltage Mode
3V< Vsense < 8.25V
100
0.75
V
5
V
220
kΩ
MEASOUT output
Vref+0.5
uA
0.05
0.5
V
0.2
V
5
mA
5%
Meas_Verr2
Error in Voltage Mode
1V< Vsense < 3V
20%
Vmeas_Voffset
Offset error in Voltage Mode
1V< Vsense < 8.25V
25
%Meas_Ierr1
Error in Current Mode
5mA< Isense <40mA
-5%
5%
IMeas_err2
Error in Current Mode
0mA< Isense <5mA
-25
25
uA
Ioffset
Forced Offset current
ENABLE = 0, VI_CTRL=1
(CM)
0.055
1
mA
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
Symbol
Parameter
Conditions
Min
Nom
Max
Unit
Voltage regulation on SENSE pins
Vsense_err1
VSENSE – VREF
3V ≤ Vref ≤5V
-100
100
mV
Vsense_err2
VSENSE – VREF
5V ≤ Vref ≤8.25V
-150
150
mV
CSENSE
Maximum capacitive load on
SENSE pins
150
nF
250
us
Miscellaneous
Trise
SENSE rising time
Tshutdown
Vref=5V
from ENABLE=1 to
V(SENSE) = [4.9, 5.1]V
0
150
Thermal Shutdown (junction)
120
150
VMEAS_OTH
MEASOUT Voltage for
Overtemperature condition
1.9
VMEAS_OTL
MEASOUT Voltage without
Overtemperature condition
IsenseLIM
Current limitation level on SENSE
pins.
RREF=1kOhm, VREF=5V
°C
V
40
0.9
V
80
mA
5. Pin assignment
PIN No.
SHORT NAME
DESCRIPTION
1
SENSE3
5V / 40mA
Driver Output
2
SENSE2
5V / 40mA
Driver Output
3
SENSE1
5V / 40mA
Driver Output
4
VSUP
Range: 8V .. 25V
Supply
5
ENABLE
TTL Levels
Digital Input
6
MUX_SENSE0
TTL Levels
Digital Input
7
MUX_SENSE1
TTL Levels
Digital Input
8
MUX_SENSE2
TTL Levels
Digital Input
9
VREF
External Voltage Reference
Analog Input
10
VI_CTRL
TTL Levels
Digital Input
11
MEAS_OUT
12
RREF
13
VSS
Ground (analog + digital)
Ground
14
SENSE6
5V / 40mA
Driver Output
15
SENSE5
5V / 40mA
Driver Output
16
SENSE4
5V / 40mA
Driver Output
3901016305
Rev. 008
FUNCTION
Analog Output
Analog Output
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
6. Block Diagram
VSUP
Voltage
Regulator
VDD
MUX_SUP[0:2]
VSENSE(ISENSE)
VREF
SENSE1
MUX_SUP[0:2]
MUX_SENSE[0:2]
VI_CTRL
VMEAS(VM)
VMEAS(CM)
SENSE2
SENSE3
SENSE4
SENSE5
SENSE6
*0.5
MEAS_OUT
ISENSE/10
Z
IOFFSET
OVERTEMP
MUX_SENSE[0:2]
ENABLE
Encoder
MUX_SUP[0:2]
*0.9
MUX_SUP[0:2]
GND
RREF
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
7. General Description
The MLX16305 simplifies the monitoring and diagnostics of up to 6 mechanical switches through voltage
and current sensing. The 6 SENSE inputs are multiplexed onto a single output pin (MEAS_OUT). The
SENSE pins can be supplied by a Voltage source that forces the Vref voltage with a current limit
(IsenseLIM).
The MLX16305 is controlled by the microcontroller through a 5 wire digital interface. This allows the
microcontroller to either apply a voltage to maximum 1 SENSE pin, or leave them high impedant. At the
same time the microcontroller can evaluate the current drawn or the voltage measured on either that
same pin or any other SENSE pin. This way the state of a mechanical switch can be read or the switches
can be diagnosed to detect open wires, shorts between SENSE pins, to Ground or to Supply.
With the VI_CTRL input the MLX16305 can be set in either Current Mode (CM) or in Voltage mode (VM)
• In current measurement mode (CM), the current drawn by the selected SENSE pin
(Isense) from the voltage source is copied onto an external resistor Rref to convert it to a
proportional voltage presented on the MEAS_OUT pin.
• In voltage measurement mode (VM) the voltage on the selected SENSE pin is copied
directly onto the MEAS_OUT pin divided by two, such as to come within the voltage rail set
by Vref.
The combination of voltage and current measurements allow diagnosing multi-level currents to detect the
state of the switch, whilst allowing to check shorts to GND and to Supply failure modes.
8. PIN description
8.1. Supply Range (VSUP)
For correct operation of the Voltage source, a minimum voltage drop is required between the supply
(VSUP) and the reference voltage (Vref). Therefore the main supply VSUP of the IC device is specified
as:
• VSUPmin =
VREF + 2.5V
for Isense ≤ 30mA
VREF + 3.5V
for Isense ≤ 40mA
VREF + 8V
for Isense ≤ 45mA
• VSUPmax =
25V
The supply current IDD is specified for disabled SENSE pins (MUX_SENSE=000b: the voltage regulator
is disabled), and represents the current drawn from VSUP.
In case a SENSE pin is pulling current, the total current consumption is the addition of:
• the internal current through the device (same as IDD)
• the current drawn by the SENSE pin (ISENSE) from the voltage regulator
• the 10:1 mirror current of ISENSE on the RREF pin
8.2. Input Voltage Reference (VREF)
The VREF pin is used as an external reference for voltage regulation on the SENSE pins. Vref also
defines the clamping level of the MEAS_OUT pin. This reference voltage is generated externally and can
vary independent of VSUP and digital input levels. In a typical example with 5V microcontrollers and 5V
Hall switches Vref is directly taken from the external 5V regulator.
Remark that even though the Hall switches are supplied at VREF, the load on VREF is limited to IVref.
The regulator that supplies the Halls is drawing its current from VSUP.
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
8.3. Voltage Regulation (SENSE)
The voltage on the SENSE pins is forced to the Vref level.
Depending on the applied Vref, the maximum deviation is specified as:
Vsense = Vref +/- Vsense_errx (see electrical specification)
•
•
•
The Voltage regulation specification is only valid for Isense and Csense values within
specification.
Maximum total capacitor load includes the wiring parasitic capacitance and Hall Switch supply
capacitor if applicable.
The Output Settling time on pins SENSE1 … SENSE6 for the selected channel is Trise after
ENABLE pin is set high.
Vref
Trise
Supply voltage
of the selected
SENSE channel
0V
ENABLE
8.4. Output voltage to the microcontroller ADC (MEAS_OUT)
The microcontroller can evaluate/diagnose the state of the interlock switch based on the voltage that its
ADC will measure on the MEAS_OUT pin.
•
•
•
The VMEASOUT output voltage is not higher than Vref + 0.5V to avoid damaging of the
microcontroller ADC input.
The MEASOUT pin is able to deliver minimum IMEAS.
MEAS_OUT can be made high impedant to allow multiplexing of 2 or more MLX16305 devices in
parallel when more than 6 channels are required.
3901016305
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
8.5. Digital Inputs
DEFINITIONS:
• Digital input pins ENABLE, VI_CTRL and MUX_SENSE[0:2] have TTL characteristic.
Additionally these pins have internal pull downs for a defined reset behavior of the complete
system.
• Logic levels : LOW : V ≤ VIL and HIGH : V ≥ VIH
•
Bit representation.
To select SENSE channel 1, set
• MUX_SENSE0: 0
• MUX_SENSE1: 0
• MUX_SENSE2: 1
In his document this is represented as MUX_SENSE[0:2]=001b
FUNCTIONALITY:
• MUX_SENSE[0:2] has a double function
o It controls the multiplexer that selects the channel that is to be sensed/measured
o And these inputs are latched into MuxSenseLatched [0:2] when ENABLE goes high.
• ENABLE has a double function
o When Enable =0 the MuxSenseLatched [0:2] signals are identical to the MUX_SENSE
inputs. When Enable=1, the MUX_SENSE signals are latched into MuxSenseLatched
[0:2]. This way a different channel can be sensed, from the one supplied (MUX_SENSE
≠ MuxSenseLatched).
o Enable resets MUX_SUP to 000b when ENABLE is logic low. This disconnects all
channels from the voltage regulator (Isense=0mA) and activates a weak pull down on all
pins.
• VI_CTRL selects Current Mode or Voltage Mode (see below)
3901016305
Rev. 008
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
8.6. ENCODER: Internal Digital Signals
•
MuxSenseLatched[0:2] signals are defined by the MUX_SENSE and ENABLE inputs. It is used
for 3 purposes:
o to go to OVERTEMP measurement mode
o to set MEAS_OUT high impedant
o to select the channel that is to be supplied with Vref.
MuxSenseLatched = MUX_SUP if ENABLE = 1
The standard relation between MUX_SENSE, ENABLE and MuxSenseLatched can be viewed as
a latch that is controlled by ENABLE:
o ENABLE = 0
then the latch is transparent: MuxSenseLatched == MUX_SENSE
o ENABLE = 1
then the latch is closed: MUX_SENSE can be changed without influencing
MuxSenseLatched.
OVERTEMP
Z
MUX_SENSE[0:2]
MuxSenseLatched[0:2]
ENABLE
MUX_SUP[0:2]
MUX_SUP[0:2]
MUX_SUP == MuxSenseLatched AND ENABLE
The MUX_SUP[0:2] signals control the multiplexer that selects the channel on which the voltage
regulator will force Vref.
1. Apply on MUX_SENSE the value of the channel that should be supplied while ENABLE is
low.
2. Then switch ENABLE high to latch this state into MuxSenseLatched.
3. As long as ENABLE stays high the selected SENSE pin will be supplied with the VREF
voltage.
4. In the mean time MUX_SENSE may change. This allows diagnostics for shorts between
SENSE pins. One channel can be supplied with Vref and another can be sensed.
(MUX_SUP ≠ MUX_SENSE)
5. As soon as ENABLE goes low again, MUX_SUP is reset to 000b, hence disabling every
channel. The weak pull down on every SENSE pin will then pull VSENSE down.
OVERTEMP (Dominant setting):
In order to set OVERTEMP = 1 MuxSenseLatch[0:2] has to be set to 111b.
o When ENABLE = 0, the Overtemp condition can be read out on the MEAS_OUT pin by
setting MUX_SENSE = 111b.
o When ENABLE turns = 1 MuxSenseLatched remains = 111b. Changes on
MUX_SENSE[0:2] are neglected (= don’t care).
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
Z or HIGH IMPEDANT (Dominant setting):
In order to set Z = 1 MuxSenseLatch [0:2] has to be set to 000b.
o When ENABLE = 0, MUX_SENSE has to be set to 000b.
o When ENABLE turns = 1 MuxSenseLatched remains = 000b. Changes on
MUX_SENSE[0:2] are neglected (= don’t care).
Mind that both OVERTEMP=1 or Z=1, are dominant settings on MEAS_OUT. This implies that
any changes on VI_CTRL and MUX_SENSE[0:2] are not visible.
MIND.
Do not confuse the latch with a flip-flop which is only sensitive during rising edge of the Enable. The latch
is transparent for input changes whilst ENABLE is low, not only during the rising edge.
Timing diagram
1
MUXSENSE[0:2]
000
2
3 4
100
000
5
6
7
001
8
9
10
010
111
ENABLE
MuxSenseLatched[0:2]
000
MUX_SUP[0:2]
000
001
000
001
010
000
010
111
000
111
OVERTEMP
Z
The above timing diagram shows how the inputs are converted internally:
In case of multiplexing 2 or more devices, the system should start up with MUXSENSE[0:2] and
ENABLE = 0 for all devices in order to avoid conflicts on the MEASOUT output.
Changes on MUXSENSE are not seen by the device as long as ENABLE is kept high.
In order to switch from one device to another device all MUXSENSE inputs are reset to 000b.
In order to start switch MUXSENSE at , all other devices should have set ENABLE high.
a. In Current Mode Channel 0 is selected, VMEASOUT = VMEAS(offset)as long as
ENABLE is low.
b. In Voltage mode, no channel is selected, so VMEAS remains 0V.
a. In CM the voltage regulator supplies current to channel 0 (Isense0). Isense0 is copied
onto RREF, and can be calculated from VMEASOUT.
b. In VM the voltage regulator supplies Vref to channel 0 (Vsense0). Vsense0 is copied on
VMEASOUT.
ENABLE remains high
a. In CM changes on MUXSENSE are neglected (don’t care)
b. In VM, the voltage is measured on channel 1, which has its weak pull down active. If
Vsense1 > 0V then a short to Channel 1 is found.
ENABLE goes low, disabling all channels while channel 1 is selected. See ENABLE goes high and low again while MUXSENSE remains unchanged.
a. In CM Isense1 can be measured while ENABLE is high.
b. In VM channel 1 is supplied with Vref and the resulting Vsense1 is copied to VMEASOUT
MUXSENSE=111b displays the OVERTEMP condition on the MEASOUT pin.
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
MUX_Sense
ENABLE
MuxSenseLatched
MUX_Sup
Z/Overtemp
VI_CTRL
MEAS_OUT
001
010
011
100
101
110
001
010
011
100
101
110
XXX
000
XXX
111
000
111
001
010
011
100
101
110
001
010
011
100
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1
0
1
1
1
1
1
1
1
1
1
1
1
1
001
010
011
100
101
110
001
010
011
100
101
110
000
000
000
000
000
000
000
000
000
000
000
000
000
111
111
other than 000/111
other than 000/111
001
010
011
100
101
110
other than 001/000/111
other than 010/000/111
other than 011/000/111
other than 100/000/111
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
1/0
1/0
0/1
0/1
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0/0
0
0
0
0
0
0
1
1
1
1
1
1
X
X
X
X
0
0
0
0
0
0
0
0
0
0
0
0
V(SENSE1)/2
V(SENSE2)/2
V(SENSE3)/2
V(SENSE4)/2
V(SENSE5)/2
V(SENSE6)/2
0V
0V
0V
0V
0V
0V
Z
Z
OVTEMP
OVTEMP
floating node
floating node
V(SENSE1)/2
V(SENSE2)/2
V(SENSE3)/2
V(SENSE4)/2
V(SENSE5)/2
V(SENSE6)/2
V(SENSEx)/2
V(SENSEx)/2
V(SENSEx)/2
V(SENSEx)/2
101
1
other than 101/000/111
0/0
0
V(SENSEx)/2
110
XXX
XXX
XXX
XXX
XXX
XXX
1
1
1
1
1
1
1
other than 110/000/111
001
010
011
100
101
110
0/0
0/0
0/0
0/0
0/0
0/0
0/0
3901016305
Rev. 008
000
000
DESCRIPTION
FAULT DETECTED on MEAS_OUT
MUX_Sup=000: SENSE pins are not supplied, and
the weak pull down is active.
MUX_Sense selects the SENSE pins to be
monitored in voltage mode VMEAS_OUT =
Vsense/2.
Normal <VMEAS_DIS;
Else VMEAS>VMEAS_DIS, then the weak
down is overruled. A short to Vbat or to an
High Voltage node is detected.
MUX_Sup=000: SENSE pins are not supplied, and
the weak pull down is active.
MUX_Sense selects the SENSE pins to be
monitored in current mode: Since there is no current
supplied, no current can be copied on RREF.
State used in application for offset measure
VMEAS_OUT(offset) = 0.9*Ioffset*Rref
MUX_Sense=000 is latched to set Z=1
MEAS_OUT is high impedant.
MUX_Sense=111 has been latched to set
Overtemp=1
OVERTEMP => VMEASOUT>VMEASOUT
else: VMEASOUT<VMEASOUT_OTL;
The output shows the state of an internal floating node.
This value is undefined because the IC tries to measure voltage on a non-existing channel
MEAS_OUT = Voltage on SENSE1 Pin divided by 2
MEAS_OUT = Voltage on SENSE2 Pin divided by 2
MEAS_OUT = Voltage on SENSE3 Pin divided by 2
MEAS_OUT = Voltage on SENSE4 Pin divided by 2
MEAS_OUT = Voltage on SENSE5 Pin divided by 2
MEAS_OUT = Voltage on SENSE6 Pin divided by 2
MEAS_OUT = Voltage on SENSE1 Pin divided by 2
MEAS_OUT = Voltage on SENSE2 Pin divided by 2
MEAS_OUT = Voltage on SENSE3 Pin divided by 2
MEAS_OUT = Voltage on SENSE4 Pin divided by 2
Normal = VREF/2 ;
Else VMEASOUT> Normal: Short to Vbat
Else VMEASOUT< Normal: Short to GND
on the sensed channel
Normal <VMEAS_DIS;
Else VMEASOUT =VREF/2 reflecting a short
between sensed channel and supplied channel
MEAS_OUT = Voltage on SENSE5 Pin divided by 2
0
V(SENSEx)/2
MEAS_OUT = Voltage on SENSE6 Pin divided by 2
1
ISENSE1*Rref/10
MEAS_OUT = Current on SENSE1 Pin
1
ISENSE2*Rref/10
MEAS_OUT = Current on SENSE2 Pin
Switch state: current levels OPEN/CLOSE
1
ISENSE3*Rref/10
MEAS_OUT = Current on SENSE3 Pin
DIAGNOSTICS:
VMEASOUT = 0
=> Open wire
1
ISENSE4*Rref/10
MEAS_OUT = Current on SENSE4 Pin
VMEASOUT > VREF*0.9: => Short to GN
1
ISENSE5*Rref/10
MEAS_OUT = Current on SENSE5 Pin
1
ISENSE6*Rref/10
MEAS_OUT = Current on SENSE6 Pin
(*)in CM VMEASOUT in the above table is the calculated value after subtracting the contribution of the offset = VMEASOUT - VMEASOUT
Page 12 of 29
Data Sheet
Jun/12
MLX16305
Interlock switch sensor interface IC
9. Voltage Mode (VM)
To go into Voltage Mode (VM) VI_CTRL is set low. In this mode the resulting voltage on the SENSE pin
(VSENSE) is copied onto the MEAS_OUT pin. For normal operating conditions (Vref>Vsense) it can be
calculated back as:
•
for 3V < VSENSE < 8.25V
-
VMEASOUT min = [VSENSE * (1 - Meas_Verr1)] / 2 - VMEASOUT_VOFFSET
VMEASOUT max = [VSENSE * (1 + Meas_Verr1)] / 2 + VMEASOUT_VOFFSET
•
for VSENSE < 3V the accuracy is reduced to Meas_Verr2.
This condition can occur
- with a short to GND
- or for detecting shorts to an external voltage below 3V. This case can be diagnosed by
selecting a pin without supplying it with the regulated voltage. Any voltage that is
measured has to be due to an external source that is connected to that pin.
•
for VSENSE > VREF (short to supply)
-
VMEASOUT max < VREF + 0.5V
This condition can be diagnosed with the SENSE pin in high impedant state (weak pull down is
active), as well as in the state with the channel is supplied with the regulated voltage.
Remark
• When a SENSE pin is measured in Voltage Mode (VM) without being supplied by the voltage
regulator, then an internal pull down keeps the voltage on that SENSE pin low, unless it is
overruled by a short to supply.
o If no short to VBAT is forced then:
VMEASOUT < VMEAS_DIS
•
When a SENSE pin is not supplied by the voltage regulator, then an internal pull down current
keeping the voltage low. However, in case of a SENSE pin shorted to a voltage higher than 20V
this pull-down current will increase when the esd protection becomes active (pull-down resistance
drops then below 3kOhms). This is not allowed during normal operation.
In case of short to voltages lower than 2V this pull-down current will decrease (resistive behavior).
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Interlock switch sensor interface IC
10. Current mode (CM)
The high accuracy of the MLX16305 can be used
•
to define clear boundaries of voltages. These boundaries will allow straightforward classification
of the state of current modulated switches.
•
to measure industry standard current modulated sensors (for instance with the MLX90308,
MLX90314)
10.1. Current to Voltage conversion principle
The current ISENSE, supplied by the voltage regulator, is copied on the RREF pin with a 10:1 ratio. This
current is converted into voltage information via the external RREF resistor. An additional offset current is
forced on Rref. This results in a voltage over the RREF resistor of
• VRREF = (ISENSE / 10 + IOFFSET) * RREF
This VRREF is then copied on the MEASOUT pin with a factor of 0.9, i.e.:
•
VMEASOUT = VRREF * 0.9
10.2. The actual measurement
In current mode 2 type of measurements can be distinguished:
1) Offset measurement
While the voltage regulator is disabled, the contribution of the internal offset current can be measured.
• VMEASOUT (Vreg is disabled) = VMEASOUT_IOFFSET
2) Actual Isense measurement
When a channel is selected and ENABLE is set high, the Isense of the selected channel will be copied on
top of the offset current onto RREF.
•
VMEASOUT _(Vreg Enabled) = VMEASOUT_ENABLED
From this we can derive
• VCALC_ISENSE = VMEASOUT_ENABLED - VMEASOUT_IOFFSET
Remarks:
• The current is always copied directly from the voltage regulator. Therefore as soon as ENABLE
has gone high to fix which channel is supplied (MUX_SUP is fixed), then MUX_SENSE becomes
don’t care!
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MLX16305
Interlock switch sensor interface IC
10.3. How to do an offset current measurement
In Current Mode (VI_CTRL is set high HIGH),
Set ENABLE = LOW.
This will set MUX_SUP[0:2] = 000
which will disable the Voltage regulator, such that no Isense current is mirrored into RREF.
Remarks:
• Possible Shorts on the SENSE channels have no influence on the offset measurement.
• Since ENABLE is low, the latch is transparent. Therefore make sure MUX_SENSE ≠ 000b or 111b in
order to avoid the Z or the Overtemp condition (MuxSenseLatched ≠ 000b or 111b)
• Offset may drift over longer periods of time and important temperature variations. Before every
measurement sequence the Offset measurement should be repeated.
• In case multiple Rref values are used for the different sense inputs – for instance to set different
sensitivity levels), then the offset voltage (VMEASOUT_IOFFSET ) has to be measured for each Rref
individually. Any change to Rref implies a new offset measurement.
• In case multiple MLX16305 devices are used in parallel, the offset should be measured and stored for
every device.
• An OPEN WIRE condition has Isense = 0mA, and as a result only Ioffset will contribute to the voltage
over Rref. Therefore
Vmeasout_enabled [Open Wire] = VMEASOUT_IOFFSET
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
10.4. Measurement Errors
Vmeasout
Worst case max
Actual value
Worst case min
+5%
-5%
+25uA
-25uA
0.05V
No Operation
Isense
5mA
In the above graph the errors values are shown in Current Mode.
Down to 5mA %Meas_Ierr1 and below 5mA IMeas_Ierr2.
For instance for Isense > 5mA, then VMEASOUT_ISENSE ~ Isense +/-5%
Remarks:
• The error over the total chain in CM (%Meas_Ierrx) does not include error due to the external
RREF resistor.
• In the full system calculation additional errors have to be added for the tolerances on the sensor
current, the ADC supply noise, etc.
3901016305
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
11. How to predict the system operating zone
11.1. VMEASout limits
The worst case output voltages, including measurement errors, on the MEAS_OUT pin can be predicted
with following formulas:
•
For 5mA < ISENSE ≤ 40mA
- VMEASOUTmin = [ISENSE /10 * (1 - %Meas_Ierr1) + Ioffsetmin ] * RREF * 0.9
- VMEASOUT max = [ISENSE /10 * (1 + %Meas_Ierr1) + Ioffsetmax ] * RREF * 0.9
•
For ISENSE ≤ 5mA
- VMEASOUTmin = [ISENSE/ 10 - IMeas_Ierr2 + Ioffsetmin ] * RREF * 0.9
- VMEASOUTmax = [ISENSE/ 10 + IMeas_Ierr2 + Ioffsetmax ] * RREF * 0.9
11.2. Isense limits
The operating range, and the corresponding maximum Isense, is defined by the Vsup-Vref range as
shown in the above graph.
Other limiting specifications are:
1) Absolute maximum allowable Isense < 90mA:
Under no condition the Isense current should be larger than 90mA, in order to avoid permanent damage
to the IC.
2) Minimum Current limitation threshold: see Overcurrent limitation (next paragraph)
3) Overtemperature shutdown: see Overtemperature Detection
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Interlock switch sensor interface IC
12. Overcurrent Limitation
The MLX16305 has a built-in overcurrent limitation as protection against destruction and overheating. It
also allows detecting short circuits to Ground on any of the SENSE channels.
The voltage regulator will enter current limitation when the voltage over the external Rref
resistance (VRREF) is between VREF and VREF + 3V:
VREF < VRREF(limit activated) < VREF + 3V
The current limitation is realized by reducing the
forced output voltage on the SENSE pin
(VSENSE), until VRREF drops below the limitation
threshold.
[mA]
The graph shows the trends of Isense (~VRREF)
and Vsense for an example where:
Vref = 5V and Rref=1kΩ.
70
6
90
80
5
4
60
As the Rsense ‘load’ drops from normal operating
range down to a short circuit condition Isense is
theoretically clamped between 40 and 80mA,
depending on Ioffset:
50
IsenselimMin = (VRef/Rref – (Ioffsetmax=1mA) )*10
20
IsenselimMax = (Vref+3)/Rref *10
10
Remark
• Under any condition, including during
current limitation it is guaranteed that
Vmeasout < Vref +0.5V
[V]
IsenseMax
IsenseMin
VsenseMax
40
3
VsenseMin
2
30
0
1
Rsense
Current
limiting
0
Operating range
The current limiting should also be taken into
account to set the minimum allowable operating
current.
The graph on the right shows the minimum Isense
limits for Rref = 1kOhm for different values of
minimum Vsup:
• Zone
is due to the current limiting
•
Zone is due to Isense Max specification
o
o
o
a: 30mA
b: 40mA
c: 45mA
Remark that Zone
will shift to the right when
increasing Rref, and to the left with reducing Rref
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MLX16305
Interlock switch sensor interface IC
Remark 1:
When reducing Rref, the absolute maximum Isense current be limited to 90mA.
For instance
• For Vref = 3V => Isenselim [20, 60]mA
So even if Vsup-Vref allows higher currents, the operating range is limited by the current limitation.
An alternative is to reduce Rref, to increase the current limit.
For instance RREF = 500Ω.
=> Isenselim [40, 120]mA
Remark that the absolute maximum Isense current should.
•
Vref = 8.25V => Isenselim [72.5, 112.5]mA
Remark that the absolute maximum Isense current is limited to 90mA.
An alternative is to increase RREF, for instance to 1500Ω.
=> Isenselim [45, 75]mA
Remark 2:
Current limitation can be monitored via the voltage on MEAS_OUT:
• In Current Mode:
VMEASOUT = [ 0.9* VREF , VREF + 0.5V ]
•
In Voltage Mode:
VMEASOUT
=
VSENSE / 2
<
VREF / 2
13. Overtemperature Detection
The MLX16305 has an internal overtemperature detection to protect against destruction and overheating.
By applying the correct sequence on the digital input pins the OVERTEMP state is readable via the
MEAS_OUT pin coded as:
•
•
VMEAS ≤ VMEAS_OTL = normal operation
VMEAS ≥ VMEAS_OTH = Overtemperature condition detected.
When an overtemperature condition is detected the supply regulator will shut down until the overtemp
condition has gone. Then diagnostics should show the root cause of the overtemperature condition.
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
13.1. Overtemperature considerations
Depending on the layout of the PCB, the thermal resistance of a narrow body SO16 package can be as
o
low as 82 C/W (ideal reference value for a 4 layer pcb).
o
For the below calculations we use 100 C/W.
The increase in junction temperature (Tj) due to energy dissipation in the linear voltage regulator can be
calculated as follows:
• Assuming worst case operating conditions VSUP=18V and Tamb = 85oC.
• And VREF=5V and RREF = 1kOhm,
EXAMPLE 1: 40mA continuous
Assuming the maximum supply current is drawn from a Sense pin, and the voltage is regulated to
Vref (no short condition)
Dissipation due the this: 40mA * (18-5)V = 0.52W
Additionally the current sources supply RREF with Isense/10 + Ioffset (<1mA)
Maximum Dissipation due the this: (40mA/10 + 1mA) * (18-5)V = 0.07W
Therefore the maximum power dissipation on the MLX16305 is 0.59W.
The maximum junction temperature is then 85oC+100oC/W*0.59W = 144oC.
This is outside the operating range.
overtemperature since Tj > Tshutdown.
Furthermore the MLX16305 may shut down due to
EXAMPLE 2: Duty Cycling
In practice the controller will scan the different SENSE outputs one by one. As described in
above (diagnostics flow) the regulator can be expected to be active for example for 0.5ms per pin,
including 250us settling time.
o
o
At Tamb = 85 C, Tj<90 C can be guaranteed as follows:
The heating of 59oC in EXAMPLE1 can be reduced by waiting 5.5ms before selecting the next pin
The flow then becomes:
0.5ms evaluating pin1 => 5.5ms off => 0.5ms evaluating pin2 => 5.5ms off => …
Or also: evaluate all 6 pins consecutively (6*0.5ms) and switch off for > 33ms
Example3: Short to GND
Short to ground implies that Vsense = 0V.
When the regulated supply is applied, then the SENSE voltage will be kept at 0V by the short, and
the internal current limitation will limit the current to for instance 50mA. Therefore the power
dissipation from the SENSE pin is
Worst case Dissipation due the short: 50mA * 18V = 0.9W
The controller will immediately diagnose the failure, and switch off the supply.
Therefore no dissipation will be due to this. Worst case the MLX16305 will go in overtemperature
and shut down itself.
3901016305
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Data Sheet
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MLX16305
Interlock switch sensor interface IC
14. DIAGNOSTICS
14.1. Shorts
Long wires to the remote switches are prone to shorts to Ground, to supply or between the wires. The
MLX16305 allows continuous failure mode diagnostics on each SENSE pin individually. The circuit works
also if one of the SENSE pins is shorted to GND or Vbat (up to +25V); this means that such a short does
not influence the measurement on other SENSE pins.
A. Shorts to GND
A short between a SENSE pin and GND can be diagnosed either in Current Mode (CM) or in Voltage
mode. The short will cause the voltage source to go in current limitation. As described in the ‘Overcurrent
limitation’ paragraph above, the voltage over Rref (VRREF) will rise to VREF.
•
•
In Current Mode (CM) over current is detected as
VMEASOUT = 0.9* VREF
In Voltage Mode over-current is detected as
VMEASOUT < VREF/2 .
This value may however also indicate an open or closed switch. Therefore it is recommended to
diagnose Shorts to GND in CM.
B. Shorts to Supply (Vsup)
A short between a SENSE pin and a high voltage level, like VIGN or even directly to the battery supply
VBAT, can be diagnosed in Voltage Mode:
Method 1: SENSE pin not actively supplied
• Set all SENSE pins high impedant (MUX_SUP[0:2]=000b),
• Then select the respective SENSE pins one by one in Voltage Mode (VM).
=> The weak pull down on each SENSE pin should yield
VMEAS < VMEAS_DIS.
Any higher value indicates a short to a Supply voltage.
Method 2: SENSE pin actively supplied
When there is a short to Supply on a pin that is supplied by the voltage regulator, then the
MEAS_OUT voltage will be larger than Vref/2.
VREF/2 < VMEASOUT < VREF
C. Shorts Between wires
A short between the wires connecting the sense pins to the remote switches can be diagnosed in a similar
way as shorts to supply:
• Select a SENSE pin. This channel will be supplied with VREF, and act as the supply in the ‘Short
to Supply’ case.
• Then select the other SENSE pins one by one in Voltage Mode (VM).
The weak pull down on the other SENSE pin should yield VMEAS < VMEAS_DIS. Any higher value
indicates a short to the selected SENSE pin. To have an unambiguous diagnostics first check ‘Shorts to
Supply’ before checking ‘Shorts between Wires’.
14.2. Open Wire
In an Open Wire condition, the regulator can not supply any current (Isense= 0mA). This condition can
not be checked in Voltage Mode. In Current Mode Ioffset will generate a signal on RREF. Therefore for
the analog measurement chain, an open wire conditions is identical to an offset measurement. Mind that
due to ±VMeas_Ierr2 it is possible that after subtraction of the Offset, a negative value may result!
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Interlock switch sensor interface IC
14.3. Diagnostics flow
Example software flow for interlock switch diagnostics:
1) Set ENABLE low
a. Set MUX_SENSEx (select channel)
b. Set to Vmode: evaluate short to vbat
2) Set ENABLE high: supply selected channel : wait 250us to allow the output to settle.
a. In the mean time set Imode.
b. 250us after ENABLE has been set high -> Evaluate the measured current value
c. Set to Vmode and evaluate short to ground
d. Set one by one all other channels to evaluate shorts between the supplied pin and the
other channels
3) Return to 1)
For further discussions in this document it assumed that the flow for 1 pin could be completed in 0.5ms
including the 250us settling time.
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Interlock switch sensor interface IC
15. Multiplexing the ADC input by setting MEAS_OUT High Impedant
By applying the correct sequence on the digital input pins the MEAS_OUT pin can be set high impedant.
This is of interest when using 2 or more MLX16305 in parallel for applications with more than 6 switches
to be monitored. The MLX16305 devices are then multiplexed on the same ADC input channel.
The AD input from the microcontroller can be shared by multiple MLX16305 devices in parallel.
With 1 extra digital IO serving as ENABLE for a second device, 6more channels can be controlled.
Procedure:
• First while ENABLE2=0, set MUX_SENSE[0:2] = 000b
• Then latch this value by setting ENABLE2 = 1
• From now on MEASOUT2 is high impedant, and regardless the values of VI_CTRL or
MUX_SENSE[0:2], this remains.
• Switching from device one to device two is done by setting MUX_SENSE[0:2] = 000b while
ENABLE1=0. Setting ENABLE1=1 makes MEASOUT1 high impedant.
• Now ENABLE2 can be reset to 0 without possible conflict between the 2 MEASOUT outputs.
K L 1 5 / IG N
VSUP
VREF
ADC
M EAS_O U T
EN ABLE1
V I_ C T R L
M U X_SEN SE0
M U X_SEN SE1
M U X_SEN SE2
M LX16305
S en se1
S en se2
S en se3
S en se4
S en se5
S en se6
R re f
M L X16305
M ic r o c tr l
3901016305
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EN ABLE2
Page 23 of 29
Sense1
Sense2
Sense3
S ense 4
S ense 5
S ense 6
R re f
Data Sheet
Jun/12
MLX16305
Interlock switch sensor interface IC
16. Application Notes
16.1. System definition example with 2-wire Hall Switches
The MLX16305 can be used with so called 2-wire Hall effect switches, like the MLX90275. These require
typically a minimum operating voltage of 3.5V, and have 2 well defined current states. For instance:
• Ioff:
[5; 6.9]mA
• Ion:
[12; 17]mA
An example is elaborated for
• Vsup > 8.5V
Mind that on the Safety ECU often higher voltages are available from the squib drivers. These can also
be used in stead of the battery voltage to further extend the operating zone.
And furthermore
• Vref = 5V • Rref=1kΩ Vsup-Vref = 3.5V Isensemax = 40mA
Isenselim > 40mA
Since the output voltage in Current Mode is undefined in case of a short to supply, we start in Voltage
Mode to diagnose this fault condition first.
VI_CTRL=0
1. Short to VBAT
All SENSE channels are disabled (ENABLE=0) and scanned one by one. If any of the output values
rises above VMEAS_DIS, this means the weak pull down is overruled by a short to the supply.
2. Short between wires.
In a similar way if one channel is supplied with Vref, all other channels can be checked on a short to
this supplied channel. If any of the output values rises above VMEAS_DIS, this means the weak pull
down on the selected channel is overruled by a short to the supplied channel. In a 6 channel
application, 15 different wire-to-wire shorts can be checked and diagnosed one by one.
VI_CTRL=1
In Current Mode (CM) 4 more conditions can be diagnosed.
STEP 1:
The first step is to guarantee that each measurement is in the target operating zone under any corner
condition. Two tolerances have to be taken into account when calculating the border values for each
condition: The offset and the measurement error.
Remark for simplicity of the example we did not calculate tolerances on external components (like Rref)
and other noise sources like ADC supply. These have to be added in a real system definition.
As calculation examples the Voltage range corresponding to the OFF state is calculated:
The minimum worst case situation is calculated using
• Ioffmin = 5mA
• Ioffsetmin = 0.055mA
• Error = - 5%
VMEASout (OFFmin) = (Isense/10 * 0.95 + Ioffsetmin) * Rref * 0.9
= 0.477 V
The maximum worst case situation is calculated using
• Ioffmax = 6.9mA
• Ioffsetmax = 1mA
• Error = + 5%
VMEASout (OFFmax) = (Isense/10 * 1.05 + Ioffsetmax) * Rref
3901016305
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* 0.9
= 1.076 V
Data Sheet
Jun/12
MLX16305
Interlock switch sensor interface IC
VMEASout (OFF)
= [ 0.477, 1.552 ] V
In a similar way the corner values for the ON condition can be calculated to be
Vmeasout (ON)
= [ 1. 076 , 2.507 ] V
Therefore all Vmeasout values are within [0.05, Vref]
STEP 2:
The actual measurement value is the subtraction of Vmeasout (Isense) - Vmeasout (Ioffset).
In voltage that would correspond to
V (OFF) = VMEASout (OFF) - VMEASout (Ioffset)
V (ON) = VMEASout (ON) - VMEASout (Ioffset)
= [ 0.430, 0.607 ] V
= [ 1.028, 1.562 ] V
Therefore the 2 states can be clearly distinguished.
Furthermore depending on the definition of an ‘open wire’ or a ‘short to ground’ similar values can be
calculated to further distinguish failure mode conditions.
16.2. Resistive Switches
Resistive switches are essentially also acting like current modulated switches. Therefore diagnostics are
done in the same manner.
The MLX16305 can supply plenty of cleaning current to allow the use of low cost switches.
Nevertheless, aging may cause drift of the contact resistance values over life. The high accuracy of the
MLX16305 allows tracking of such a case and early triggering of eminent failures.
16.3. 2-wire analog sensors
Industrial sensors and sensor interfaces like the MLX90308 have a 4 to 20 mA current range. The
MLX16305 can be used to sequentially read them out.
The offset and any non-linearity induced by the 16305 in current mode can be calibrated together with the
sensor in production such that a VMEASOUT value is directly related to the sensor output.
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Interlock switch sensor interface IC
16.4. Ground Shift
CONNECTOR
The MLX16305 allows connecting a remote ‘2-wire’ hall sensor with only 1 wire.
Since the current is directly sensed, the measurement itself is immune to ground shift.
Furthermore [Vref – Vgroundsift] should be guaranteed to be larger than the minimum supply current for
the hall sensor. For instance for Vsupmin = 3.5V, and Vref = 5V, a groundshift of 1.5V is acceptable.
Therefore the ground can be taken local from the chassis, reducing the connector pin count on the safety
ECU, and reducing the wiring of the cables from the ECU to the remote sensors.
MCU
ADC
VDD
10nF
GND
V OUT
CONNECTOR
A) 3-Wire Hall
MCU
ADC
VDD
IOUT
VDDmin
10nF
GND
ISENSE
B) 2-Wire Hall
ADC
CONNECTOR
MCU
MLX16305
ISENSE
VDD
VDDmin
IOUT
10nF
GND
C) ‘Single’-Wire Hall using MLX16305
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Interlock switch sensor interface IC
17. Standard information regarding manufacturability of Melexis
products with different soldering processes
Our products are classified and qualified regarding soldering technology, solderability and moisture
sensitivity level according to following test methods:
Reflow Soldering SMD’s (Surface Mount Devices)
•
•
IPC/JEDEC J-STD-020
Moisture/Reflow Sensitivity Classification for Nonhermetic Solid State Surface Mount Devices
(classification reflow profiles according to table 5-2)
EIA/JEDEC JESD22-A113
Preconditioning of Nonhermetic Surface Mount Devices Prior to Reliability Testing
(reflow profiles according to table 2)
Wave Soldering SMD’s (Surface Mount Devices) and THD’s (Through Hole Devices)
•
•
EN60749-20
Resistance of plastic- encapsulated SMD’s to combined effect of moisture and soldering heat
EIA/JEDEC JESD22-B106 and EN60749-15
Resistance to soldering temperature for through-hole mounted devices
Solderability SMD’s (Surface Mount Devices) and THD’s (Through Hole Devices)
•
EIA/JEDEC JESD22-B102 and EN60749-21
Solderability
For all soldering technologies deviating from above mentioned standard conditions (regarding peak
temperature, temperature gradient, temperature profile etc) additional classification and qualification tests
have to be agreed upon with Melexis.
The application of Wave Soldering for SMD’s is allowed only after consulting Melexis regarding assurance
of adhesive strength between device and board.
Melexis is contributing to global environmental conservation by promoting lead free solutions. For more
information on qualifications of RoHS compliant products (RoHS = European directive on the Restriction
Of the use of certain Hazardous Substances) please visit the quality page on our website:
http://www.melexis.com/quality.aspx
18. ESD Precautions
Electronic semiconductor products are sensitive to Electro Static Discharge (ESD).
Always observe Electro Static Discharge control procedures whenever handling semiconductor products.
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Data Sheet
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Interlock switch sensor interface IC
19. Package Information
Unit : mm
Package Type
SOIC16
Narrow Body
3901016305
Rev. 008
min
D
9.80
E
3.80
H
5.80
A
1.35
A1
0.10
max
10.00
4.00
6.20
1.75
0.25
e
b
0.33
L
0.40
α
0º
0.51
1.27
8º
1.27
Page 28 of 29
Package Code
DC16
Data Sheet
Jun/12
MLX16305
Interlock switch sensor interface IC
20.
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 life-support 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.
© 2012 Melexis NV. All rights reserved.
For the latest version of this document, go to our website at
www.melexis.com
Or for additional information contact Melexis Direct:
Europe, Africa, Asia:
Phone: +32 1367 0495
E-mail: [email protected]
America:
Phone: +1 248 306 5400
E-mail: [email protected]
ISO/TS 16949 and ISO14001 Certified
3901016305
Rev. 008
Page 29 of 29
Data Sheet
Jun/12