MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
1. Features and Benefits
2. Application Examples
Analog Signal Processing
Quad Switched Hall Plate
Chopper Stabilized Amplifier
Linear Analog Ratiometric Output Voltage
Programmable Output Quiescent Voltage (VOQ)
-100%VDD…200%VDD Range
Programmable Magnetic Sensitivity
Programmable Low Pass Filter
Programmable Clamping Voltage
Programmable Temperature Compensation
Melexis ID Number
Programmable Customer ID Number
Lead-free package
Linear Position Sensing
Rotary Position Sensing
Current Sensing
Magnetic Field Measurement
Ordering Information
Product Code
MLX90251
MLX90251
MLX90251
MLX90251
MLX90251
MLX90251
MLX90251
MLX90251
Temperature Code
E
E
E
E
L
L
L
L
Legend:
Temperature Code:
Package Code
VA
VA
VA
VA
VA
VA
VA
VA
Option Code
FAA-000
FAA-100
FAA-200
FAA-300
FAA-000
FAA-100
FAA-200
FAA-300
Packing Form Code
BU
BU
BU
BU
BU
BU
BU
BU
Package Code:
Option Code:
Packing Form:
L for Temperature Range -40°C to 150°C
E for Temperature Range -40°C to 85°C
VA for Plastic Single in Line thickness 1.1 -1.2mm
See section 10.4
BU for Bulk
Ordering example:
MLX90251LVA-FAA-000-BU
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
3. Functional Diagram
Supply
4. General Description
1
Filter
OPA
OPA
OPA
4
3
DAC
DAC
DAC
DAC
DAC
DAC
2
Shift Register
E E P R O M
Figure 1-1 Functional Diagram
VDD
Test
VSS (Ground)
VOUT
Pin Out
VA package
1
2
3
4
Program
decoder
The MLX90251 is a CMOS Programmable, Ratiometric
Linear Hall Effect sensor IC. The linear output voltage is
proportional to the magnetic flux density. The
ratiometric output voltage is proportional to the
supply voltage. The MLX90251 possesses active error
correction circuitry, which virtually eliminates the
offset errors normally associated with analog Hall
Effect devices. All the parameters of the MLX90251
transfer characteristic are fully programmable. The
VOQ (VOUT @ B = 0 Gauss), the Sensitivity, the slope
polarity, the Output Clamping levels, the thermal
Sensitivity drift, the internal bias point and a low-pass
filter are all programmable in end-user applications.
The MLX90251 has a very stable thermal
compensation for both the Sensitivity and the VOQ over
a broad temperature range. For traceability purpose
the MLX90251 will carry a unique ID number
programmed by Melexis and 24 bits of EEPROM
memory are allocated for a user programmed serial
number.
Table 1: Pin out
Table of Contents
1. Features and Benefits ................................................................
................................................................................................
........................................................................................
........................................................ 1
2. Application Examples ................................................................
................................................................................................
.........................................................................................
......................................................... 1
3. Functional
Functional Diagram ................................................................
................................................................................................
............................................................................................
............................................................ 2
4. General Description ................................................................
................................................................................................
...........................................................................................
........................................................... 2
5. Glossary of Terms................................................................
................................................................................................
...............................................................................................
............................................................... 4
6. Maximum Ratings ................................................................
................................................................................................
..............................................................................................
.............................................................. 4
7. Detailed Block Diagram ................................................................
................................................................................................
......................................................................................
...................................................... 5
7.1. Detailed Description ........................................................................................................................ 5
8. General Electrical Specifications................................................................
................................................................................................
.........................................................................
......................................... 6
9. Programming Range ................................................................
................................................................................................
...........................................................................................
........................................................... 7
10. Timing Specifications................................................................
................................................................................................
........................................................................................
........................................................ 7
11. Accuracy................................................................
................................................................................................
................................................................................................
...........................................................................
........................................... 7
12. Programmable Features ................................................................
................................................................................................
...................................................................................
................................................... 8
12.1. Output Quiescent Voltage (VOQ) ................................................................................................... 9
12.2. Thermal VOQ Drift (DRIFT) .............................................................................................................. 9
12.3. Sensitivity, Rough Gain and Fine Gain .......................................................................................... 9
12.4. Sensitivity Range Selection.......................................................................................................... 10
12.5. Sensitivity Polarity (INVERT) ........................................................................................................ 13
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
12.6. Clamping Levels (CLAMPLOW, CLAMPHIGH) ............................................................................. 13
12.7. Filter (FILTER) ............................................................................................................................... 14
12.8. Sensitivity Temperature Compensation (TC, TCW, TC2) ............................................................ 14
12.9. Diagnostic Output Level (FAULTLEV) .......................................................................................... 15
12.10. The EEPROM, Parity, and Melexis CRC ..................................................................................... 15
12.11. Output Amplifier Configuration (MODE).................................................................................. 15
12.12. Memory Lock (MEMLOCK) ........................................................................................................ 16
12.13. IC traceability ............................................................................................................................. 16
13. Performance
Performance Graphs ................................................................
................................................................................................
......................................................................................
...................................................... 16
14. Applications Information ................................................................
................................................................................................
................................................................................
................................................ 17
14.1. Application Circuits – VA-package .............................................................................................. 17
14.2. Programming the Sensor ............................................................................................................ 17
14.3. Calibration Procedure ................................................................................................................. 18
15. Standard information regarding manufacturability of Melexis products with different soldering
processes ................................................................
................................................................................................
................................................................................................
.............................................................................
............................................. 19
16. ESD Precautions ................................................................
................................................................................................
.............................................................................................
............................................................. 19
17. Package Information ................................................................
................................................................................................
......................................................................................
...................................................... 20
17.1. VA Package Outline and Hall Plate Position ............................................................................... 20
18. Contact................................
Contact................................................................
................................................................................................
................................................................................................
...........................................................................
........................................... 21
19. Disclaimer ................................................................
................................................................................................
................................................................................................
......................................................................
...................................... 21
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
5. Glossary of Terms
Term
Explanation
mT (milli-Tesla)
Unit of measurement for magnetic flux density. 1mT is equal to 10 Gauss.
VOQ (Output Quiescent Voltage)
Output voltage at zero magnetic field, VOUT for B = 0 mT.
Sensitivity
Change in output voltage versus change in magnetic field (Δ VOUT / Δ B)
TempCo (Sensitivity
Temperature Compensation)
PTC (Programming Through the
Connector)
Change in Sensitivity over temperature.
Listed in units of ppm / °C (where 100ppm / °C. = 0.01% / °C)
MSB
Most Significant Bit.
LSB
Least Significant Bit.
Melexis in-circuit programming protocol.
6. Maximum Ratings
Parameter
Units
Maximum Supply Voltage, VDD_MAX
(over Voltage)
30 V
Maximum Supply Current, IDD_MAX
(Over Voltage)
50 mA
Reverse Voltage, VDD_REV
- 15 V
Reverse Supply Current, IDD_REV
- 85 mA
Positive Output Voltage, VOUT_MAX
24 V
Positive Output Current, IOUT_POS_FAULT
40 mA
Reverse Output Voltage, VOUT_REV
- 0.7 V
Reverse Output Current, IOUT_REV_FAULT
-50 mA
Operating Ambient Temperature
Range, TA
-40°C to 150°C
Storage Temperature Range, TS
-55°C to 165°C
Magnetic Flux Density
Infinite
Table 2: Absolute Maximum Ratings
Note: Exceeding the absolute maximum ratings may cause permanent damage. Exposure to absolute-maximum-rated
conditions for extended periods may affect device reliability.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
7. Detailed Block Diagram
Figure 5-1 Detailed Block Diagram
7.1. Detailed Description
Integrated on the MLX90251 is a temperature-compensated quad switched Hall plate, chopper stabilized amplifiers,
adjustable output filter, output driver, voltage protection circuitry and a programmable EEPROM with security and
redundancy. Programming the EEPROM allows each device to be calibrated in the application.
In normal operation data stored in the EEPROM feeds a register, RAM that updates internal DACs and switches that
effect the operation of the device. In programming mode the RAM can be directly accessed to allow faster calibration
of the parameters. Communication to the device is done using Melexis' PTC serial interface.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
8. General Electrical Specifications
DC operating parameters at VDD = 5V (unless otherwise specified) and for TA as specified by the temperature range (E
or L).
Parameter
Symbol
Nominal Supply Voltage
Test Conditions
Min
Typical
Max
Units
VDDNOM
-
5
-
V
1
4.5
-
5.5
V
Operating Supply Voltage
VDD
Nominal Supply Current
IDDNOM
VDD = VDDNOM
4.0
7.0
8.0
mA
Supply Current
IDD
VDD = 4.5 … 5.5 V
3.0
-
9.0
mA
VOUTPD
Pull Down Load ≥ 10 kΩ
no clamping
2
96
%VDD
VOUTPU
Pull Up Load ≥ 10 kΩ
no clamping
5
97
%VDD
IOUT
VDD = VDDNOM
-1.25
1.25
mA
-12
4
-4
12
mA
mA
0.5
%VDD
Output Voltage Swing
Output Current
Output Short-Circuit
Current
IOUTSC+
IOUTSC-
VDD = VDDNOM
Output shorted to supplypermanent
Output shorted to groundpermanent
VOUT1
Broken supply,
Pull-down load > 10 kΩ
0
VOUT2
Broken ground,
Pull-down load > 10 kΩ
94
96
100
%VDD
VOUT3
Broken supply,
Pull-up load > 10 kΩ
0
3
5
%VDD
VOUT4
Broken ground,
Pull-up load > 10 kΩ
99.5
100
%VDD
Power on Reset
VDD_POR
Voltage on VDD
1.5
3.8
V
Over Voltage Detection
VDD_OVD
Voltage on VDD
6.5
8.5
V
Diagnostic Output Voltage
Table 3: Electrical Specifications
1
The ratiometric output voltage is proportional to the supply voltage. When using the supply voltage as a reference for
an A/D converter, fluctuations of ±10% in supply voltage are compensated.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
9. Programming Range
TA programming 20°C to 30°C.
Parameter
Symbol
Test Conditions
Min
Output Quiescent Voltage
VOQ
AGND = Default
AGND = 0…1023
Sensitivity
S
Output Clamping Voltage
Low
ClampLo
Output Clamping Voltage
High
ClampHi
Temperature Compensation TempCo
Max
Units
-10
-100
110
200
%VDD
%VDD
2.6
210
mV/mT
0
100
%VDD
0
100
%VDD
0
2300
ppm / °C
st
1 order
Typical
Table 4: Programming Range Specifications
10. Timing Specifications
DC operating parameters at VDD = 5V (unless otherwise specified) and for TA as specified by the temperature range (E
or L).
Parameter
Symbol
Test Conditions
Power On Delay
TPO
FILTER = 0, RG = 0
FILTER = 0, RG = 15
FILTER = 15, RG = 0
FILTER = 15, RG = 15
Step Response Time
RG = 0 to 3, FILTER = 0
RG = 4 to 7, FILTER = 0
RG = 8 to 11, FILTER = 0
RG = 12 to 15, FILTER = 0
Min
Typical
Max
Units
0.4
0.6
1.1
5
0.8
1.2
2.2
10
ms
ms
ms
ms
32
64
132
264
μs
μs
μs
μs
24
48
100
200
Table 5: Timing Specifications
11. Accuracy
DC operating parameters at VDD = 5V (unless otherwise specified) and for TA as specified by the temperature range (E
or L).
Parameter
Thermal Voq Drift
††
Symbol
T
Δ VOQ
Life Time Drift of the L T
Δ Δ VOQ
Thermal Voq Drift
L
Life Time Voq Drift
Δ ΔVOQ
L
Life Time Sensitivity Drift
Δ ΔS
2
Test Conditions
2
VOQ = 2.5V , 25°C / 150°C
2
VOQ = 2.5V , 25°C / -40°C
Min
Typical
Max
Units
- 0.2
- 0.4
+ 0.2
+ 0.4
%VDD
%VDD
- 0.2
+ 0.2
%VDD
- 0.3
-1
+ 0.3
+1
%VDD
%
For other test conditions, please contact the Melexis Sales representative of your area.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
Sensitivity
3
Coefficient
Temperature TCs
Thermal Drift of Sensitivity
Temperature Compensation
Thermal
Drift
Output
Clamping Levels
Life Time Drift Output
4
Clamping Levels
Linearity error
0 to 500 ppm / °C
500 to 1200 ppm / °C
1200 to 2300 ppm / °C
VA-package
GO-package
T
- 0.4
± 100
± 150
± 200
150
250
+ 0.4
L
- 0.2
+ 0.2
T
Δ TC
Δ VOUTCLAMP
Δ VOUTCLAMP
Le
0.2
ppm / °C
ppm / °C
ppm / °C
ppm / °C
%VDD
%VDD
%
Table 6: Accuracy Specifications
12. Programmable Features
The MLX90251 has many programmable features for adjusting the output characteristic. The features are utilized by
writing data into the redundant non-volatile EEPROM. Below is a quick list and description of all the programmable
parameters. Many of the parameters are set by Melexis and they are not used by the end customer. Later sections of
the data sheet give details on how the parameters are used.
Parameter
Symbol
Description
Number of Bits
Default
AGND
Coarse adjustment of VOQ.
10
Trimmed
Analog Clock Choice
CKANACH
Adjustment for amplifier clock generator.
2
Preset
Clamping High
CLAMPHIGH Adjustment of upper output clamping
voltage.
10
512
Clamping Low
CLAMPLOW Adjustment of lower output clamping
voltage.
10
512
CUSTID
Open bits for customer’s ID
programming.
24
Preset
DRIFT
VOQ temperature drift compensation.
4
Trimmed
EEPROM Fault Level
FAULTLEV
Output state for EEPROM parity error.
1
0
Fine Gain
FG
Fine adjustment for Sensitivity.
10
0
Filter
FILTER
Adjustment for low pass output filter.
4
0
Invert Slope
INVERT
Sensitivity polarity selection.
1
0
Memory Lock
MEM_LOCK Used to lock the entire EEPROM.
1
0
Internal Bias Point
†
††
Customer ID
Offset Drift
Melexis ID
†
†
MLX_ID
Melexis IC identification number.
MLX_LOCK
Used to lock Melexis area of the EEPROM.
1
0
MODE
Adjustment for output stage amplifier.
2
1
OFFSET
Fine adjustment of VOQ.
10
0
OSCADJ
Chip oscillator frequency adjustment.
4
Preset
EEPROM Parity
PARITY
Ensures the integrity of the EEPROM data.
3
Calculated
Rough Gain
RG
Rough adjustment for Sensitivity.
4
0
SLOW
Amplifier speed adjustment.
1
Preset
Melexis Lock
†
Output Driver
†
Offset DAC
Oscillator Adjust
†
Slow
3
4
†
Preset
Valid for Rough Gain within the specified option code.
L
∆ = Life Time Drift (based on HTOL data [1000 hours @ 150°C]).
T
∆ = Thermal Drift.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
Temperature
Compensation Window
TCW
Range adjustment for Sensitivity
Temperature Compensation.
3
0
Temperature
Compensation
TC
Fine adjustment of Sensitivity
Temperature Compensation.
5
0
Linearization adjustment of the Sensitivity
Temperature Compensation.
6
0
2nd Order Temperature TC
Compensations
2
Table 7: Programmable Parameters
†
Melexis parameter adjusted at final test.
Not included in redundant area of the EEPROM.
††
12.1. Output Quiescent Voltage (VOQ)
Two parameters, AGND and OFFSET, are used for adjustment of the VOQ. The AGND is a 10 bit parameter for coarse
adjustment of VOQ. It has a resolution of approximately 0.014V and a range from -100%VDD to 200%VDD. The OFFSET is
a 10 bit parameter with a resolution of approximately -0.005V. The OFFSET parameter is used for fine adjustment of
the VOQ, while the AGND parameter is used to set the range. The large adjustable range allows the MLX90251 to be
used in an unipolar magnetic system without limiting the output voltage span. The formula below shows how the
AGND and OFFSET parameters combine to set the VOQ.
14.25V
5.0V
VOQ = −0.75V +
∗ AGND + −
∗ OFFSET
1023
VDD =5.00V
1023
This formula approximates the typical VOQ of the MLX90251. The actual VOQ formula varies slightly from chip to chip.
Melexis calibrates the AGND setting during final test so that the VOQ is approximately 50%VDD with OFFSET set to 512.
This gives the VOQ a range of 0%VDD to 100%VDD without adjusting the AGND value. The OFFSET parameter is often
used to set the offset in the application's output transfer characteristic.
12.2. Thermal VOQ Drift (DRIFT)
The Thermal VOQ Drift is tuned using 4 bits. This parameter, DRIFT, is calibrated for each unit by Melexis during final
test. The value is set to achieve a VOQ accuracy below 10mV over a temperature span of 25°C to 150°C. This parameter
is not used by the end customer.
12.3. Sensitivity, Rough Gain and Fine Gain
The Sensitivity of the MLX90251 is controlled through parameters linked to dedicated internal amplification stages.
The parameter Rough Gain (RG), or pre-amplifier, has 4 bits for adjustment of two stages. The two MSB affect the
Differential Input Differential Output (DIDO) stage. The two LSB effect the Differential to Single output (DTS) stage.
The gain of both the DIDO and DTS are multiplied to get the total RG. The table below shows the theoretical small
signal amplifier gain vs. the parameter RG. The pre-amplifier is chopper stabilized and the refresh frequency is
adapted automatically to the RG setting to match the chopper gain-bandwidth product.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
Rough Gain (MSB LSB)
DIDO
DTS
Gain
00 (00 00)
01 (00 01)
02 (00 10)
03 (00 11)
04 (01 00)
05 (01 01)
06 (01 10)
07 (01 11)
08 (10 00)
09 (10 01)
10 (10 10)
11 (10 11)
12 (11 00)
13 (11 01)
14 (11 10)
15 (11 11)
16
16
16
16
39
39
39
39
82
82
82
82
205
205
205
205
1.0
1.5
2.33
4.0
1.0
1.5
2.33
4.0
1.0
1.5
2.33
4.0
1.0
1.5
2.33
4.0
16
24
37
64
39
59
91
156
82
123
191
328
205
308
477
820
Table 8: MLX90251 Rough Gain Small Signal Amplifier Gain
The MLX90251 also has an additional stage, Fine Gain, for fine tuning the Sensitivity. The stage (parameter FG) follows
the RG and provides a 10 bit adjustment. The small signal gain of the FG is within 1.0 and 2.5. The RG and FG
parameters are adjusted in the application to calibrate the device's sensitivity (gain) and output slope transfer
characteristic. The function for the fine gain is given in the following equation:
Fine Gain =
1
1 − 0 .6 *
FG
1023
Note. The one bit parameter INVERT is used to fix the “sign” of the sensitivity. A value of 0 makes the Sensitivity
positive and the output voltage increases in response to an increasing South magnetic field. A value of 1 makes the
Sensitivity negative and the output voltage decreases in response to an increasing South magnetic field. Refer to
section 10.5, Sensitivity Polarity, for more information on INVERT.
12.4. Sensitivity Range Selection
Each unit is characterized over temperature during final test to optimize its performance and accuracy. To achieve the
best possible Sensitivity Temperature Compensation, TempCo, each unit is optimized for use within a specific
Sensitivity range. This is represented in the ordering information by the option code. There are four available ranges,
option codes 0, 1, 2 and 3. The option code corresponds with the two MSB of the RG parameter. Each device is tested
to meet the TempCo specification in the Sensitivity range determined by the RG parameter (RG = 0...3, RG = 4…7, RG =
8…11 or RG = 12…15), regardless of the FG parameter.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
Option Code
Rough Gain
xxx-000
xxx-100
xxx-200
xxx-300
0-3 (00 xx)
4-7 (01 xx)
8-11 (10 xx)
12-15 (11 xx)
Sensitivity Range
(mV/mT)
2.6 < S < 15
10 < S < 35
18 < S < 90
50 < S < 210
Typical Magnetic Field Range
(mT, BMAX - BMIN)
333 < B < 800
156 < B < 333
62 < B < 156
6 < B < 62
Table 9: Optimized Sensitivity Range (Rough Gain = RG)
The next figures show the typical Sensitivity versus the FG and RG parameters. The gray areas are representative of
the chip to chip dispersion (i.e.: for the same RG and FG parameters, the Sensitivity can vary from chip to chip). There
is a large overlap between the different ranges for use of one range for applications with large magnetic and/or
mechanical dispersions. The Sensitivity graphs and tables can be used to select the right device type for the
application. If one is unsure of the applications magnetic design and the desired Sensitivity range Melexis recommends
option code 2.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
Figures 10.4-1…10.4-4 Sensitivity versus RG and FG, The first (bold) digit in Table 9 is the sensitivity range.
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
12.5. Sensitivity Polarity (INVERT)
INVERT)
The slope transfer characteristic defines the Sensitivity. The INVERT parameter changes the Sensitivity's polarity, or
the slope's direction. This allows the device to accommodate the application requirements and the magnet's polarity.
The slope is inverted in the first stage of the IC, at the Hall plate. With INVERT set to 0, the output voltage increases
when an increasing South magnetic field is applied and decreases in the presence of an increasing North magnetic
field. An INVERT value of 1 causes the output voltage to increase in the presence of a North magnetic field and
decrease in the presence of a South magnetic field. The magnetic field polarity is referenced to the field component
perpendicular to the top-face of the MLX90251.
12.6. Clamping Levels (CLAMPLOW, CLAMPHIGH)
Two independent values, called the clamping levels, can limit the output voltage range or swing. The CLAMPLOW
parameter adjusts the minimum output voltage level, ClampLo. The CLAMPHIGH sets the maximum output voltage
level, ClampHi. Both parameters have 10 bits of adjustment with a resolution of approximately 0.005V. The formulas
below give a close approximation of the output clamp voltage. The actual clamping level formulas vary slightly from
chip to chip. If CLAMPLOW exceeds CLAMPHIGH the output voltage is fixed at the high clamp voltage level. The
CLAMPHIGH and CLAMPLOW have an initial value of 512, set by Melexis. This results in a fixed output voltage of
approximately 50% VDD.
ClampLo =
5.10V
∗ CLAMPLOW
1023
V DD = 5.00V
ClampHi =
5.10V
∗ CLAMPHIGH
1023
V DD = 5.00V
At the point the output voltage switches between the linear operating region and the clamping region the output can
deviate slightly. This is represented by the grey areas in the figure below. The limits for deviation in the Y axis are
listed in Table 10. The deviation in the X axis is calculated from the application's transfer function. The Clamp
Comparator Offset does not affect the output linearity or clamp voltage accuracy. During calibration it is
recommended to set the clamp voltage outside of the transition region (0V to 5V).
VOUT
CLAMP HIGH
Linear Operating
Region
CLAMP LOW
Transition Point
FIELD
Figure 10.6 Output Voltage Clamping Deviation
DC operating parameters at VDD = 5V (unless otherwise specified) and for TA as specified by the temperature range (E
or L).
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MLX90251
Programmable Linear Hall Effect Sensor
Datasheet
Parameter
Symbol
Clamp Comparator Offset
CLAMPOFF
Test Conditions
Min
Typical
- 0.7
Max
Units
+ 0.7
%VDD
Table 10: Clamp Comparator Offset Specification
12.7. Filter (FILTER)
The MLX90251 includes two programmable low-pass filters located within the chopper amplifier stages. The two lowpass filters are controlled through a 4 bit parameter, FILTER. The FILTER value 0 corresponds to minimum filtering,
maximum speed (impulse response time), and maximum output noise. The value 15 provides the maximum filtering,
minimum speed, and minimum output noise. It is important to note the noise is also linked to the gain settings. The
FILTER parameter needs to be adjusted to achieve optimal performance. The next table shows typical values the cutoff frequency at -3 dB versus FILTER and RG parameters. FILTER values from 8 to 11 are not used. For most
applications FILTER values 7 or 15 are recommended.
Cut-off frequency at -3 dB (Hz) – Typical
Filter
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
MLX90251-000
Rough Gain 0…3
22900
19500
12300
10400
7450
5850
5700
5050
2200
1000
920
800
MLX90251-100
Rough Gain 4…7
14300
11450
10000
6750
3900
2900
2700
2550
840
480
380
330
MLX90251-200
Rough Gain 8…11
7000
5550
3000
2100
1500
1125
1350
1380
Not used
Not used
Not used
Not used
565
470
290
250
MLX90251-300
Rough Gain 12…15
3850
2950
2300
1100
850
860
715
650
250
190
155
135
Table 11: Cut-off Frequency versus FILTER and RG Parameters
12.8. Sensitivity Temperature Compensation
Compensation (TC,
(TC, TCW,
TCW, TC2)
The change in the device's Sensitivity versus temperature is defined as the Sensitivity Temperature Compensation,
TempCo. In an application the slope output transfer characteristic is often affected by temperature. Fluctuations in
temperature can cause variations in the air gap, mechanical alignment and magnetic field. The Sensitivity
Temperature Compensation feature compensates for these effects.
2
Three parameters, TC, TCW, TC are used for adjustment of the TempCo. The TCW is used to adjust the TempCo range,
2
TC is for fine adjustment of the TempCo value, and TC effects the TempCo linear response. To simplify use of these
parameters Melexis stores a look up table within the EEPROM of each device. The look up table is optimized for each
device by characterizing the unit over temperature at final test.
The value of TempCo is often determined by the magnet. In the application the TempCo is adjusted to compensate for
the temperature coefficient of the magnet. To adjust the value the look up table is read from the device. The
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parameters are then calculated to match the desired value. The Melexis PTC hardware and software tools contain
built in functions for programming the TempCo.
TempCo Range (ppm / °C)
Accuracy (ppm / °C)
0 to 500
500 to 1200
1200 to 2000
± 100
± 150
± 200
Table 12: TempCo Accuracy
Note: The budget error of the whole system, the compensation mismatch (system Vs. IC) tolerance should be taken into
consideration during the design. Table 11 is valid for Rough Gain within the specified option code. See section 10.4 for
information on selecting the option code.
12.9. Diagnostic Output Level (FAULTLEV)
The MLX90251 EEPROM memory content is secured through a parity check. This self-diagnostic feature brings the
output to a defined range in case of a parity error. The parameter, FAULTLEV, is used to define the parity error
diagnostic state. With the FAULTLEV set to 0 a parity error event will result in an output diagnostic voltage low. With
the FAULTLEV set to 1 a parity error event will result in an output diagnostic voltage high. To get rid of the output load
influence the output diagnostic voltage level can be fixed to either Ground (to be used with pull-down load) or VDD (to
be used with pull-up load). Melexis PTC software and hardware tools have built in functions for calculating and
programming the parity.
Note: The MLX90251 EEPROM is also redundant. Each parameter bit is written in three separate cells and a “majority
voting” is applied to determine its status. A parity error is detected only if two out of the three cells unexpectedly
change state. The bits available for the customer ID are not redundant.
12.10. The EEPROM,
EEPROM, Parity, and Melexis CRC
The memory cells of the EEPROM are arranged in a table of four columns and one hundred twenty eight rows. This
configuration gives redundancy to the parameters stored in the EEPROM. Each parameter bit is written in three
separate cells in an individual row. A majority voting applied to the three cells determines the logic status of the bit.
A parameter bit only toggles state in error if two out of three memory cells, within a row, unexpectedly change. If this
happens the feature, PARITY, forces the output voltage to the FAULTLEV diagnostic level. This ensures the device does
not operate with a critical memory fault.
The remaining memory cells are used for data storage. The status of these cells does not effect the device operation.
For example the Customer ID, CUSTID, is stored in this area. Melexis stores the device ID information, TempCo look-up
table and CRC bits in the extra cells. The CRC bits ensure the integrity of the Melexis data.
Note: To avoid parity and CRC errors, the entire contents of the EEPROM must be read before programming. Melexis
PTC software and hardware tools have built in functions for reading the EEPROM and handling parity.
12.11. Output Amplifier Configuration (MODE)
The output buffer can be configured to accommodate capacitive loads and improve the saturation voltage (output
swing). The two bit parameter, MODE, sets the current capacity of the output amplifier. Melexis sets this parameter
to 1 at final test. This parameter is not used by the end customer.
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12.12. Memory Lock (MEMLOCK)
The Memory Lock feature prevents the device from entering programming mode and from any changes to the
EEPROM. The entire EEPROM is locked by setting the MEMLOCK parameter to 1. This should be the last parameter set
in the application.
12.13. IC traceability
A unique ID number is programmed into the EEPROM of every IC. The ID number gives Melexis additional traceability
to better service its customers. The ID number is composed of the lot number, wafer number, and wafer coordinates
(X and Y). Memory is also available for the customer to add a serial number of the product or any other data.
13. Performance Graphs
Typical IDD VS VDD
Typical IDD VS VDDNOM
60
8.5
20
8
Over Voltage
40
V
DDNOM
7.5
Under Voltage
0
IDD (mA)
IDD (mA)
7
-20
6.5
6
-40
5.5
150°C
-40°C
25°C
-60
-80
-10
0
10
20
150°C
-40°C
25°C
5
30
4.5
4
VDD (Volts)
4.5
5
5.5
6
VDD (Volts)
Figure 11-1…11-2 IDD Versus VDD
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14. Applications Information
14.1. Application Circuits
Circuits – VAVA-package
Pin 2, TEST, is not used in applications. For EMC protection it is recommended to connect pin 2 to pin 3, Ground, as
close as possible to the device pins. The values for capacitors, C1 and C2, can be adjusted to satisfy ESD and EMC
requirements according to the environment. Ceramic capacitors are recommended for use in the application. However
for stable operation, the global output capacitor (C2 + C3) should not be higher than 150nF. If higher capacitors (due
to special ESD or EMC requirements) or special circuit configurations are requested, please contact Melexis.
The MLX90251 can operate with a high impedance load and C2, a load resistor is not required.
Figures 12.1-1…12.1-2 Application Circuits
A voltage of 9V is required on VDD for programming. All additional components connected to VDD must be able to
withstand the voltage. The MLX90251 is designed for operation with a stable 5V supply. If fast voltage transients occur
additional filtering may be required.
14.2. Programming the Sensor
To program the MLX90251 connection to VDD, GND, and VOUT is required. The device is placed into program mode by
increasing the supply voltage to the VDD program level. In program mode data is clocked into the device through the
output pin using the Melexis tri-level PTC protocol. The clock and data are integrated into one serial data stream,
eliminating the need for a dedicated clock signal. The data is clocked at the leading edge of each bit.
Figure 12.2-1 VDD Programming Level
Figure 12.2-2 Tri-Level PTC
Note: External capacitors and resistors will affect the rise and fall times for the programming waveforms. Program
pulse timings may require adjustment for the application. The device cannot be programmed if MEMLOCK equals 1.
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The EEPROM contents can be read from the device. This procedure, known as a read back, is done by sending a read
command and then measuring the supply current. To successfully read the EEPROM it must be possible to measure the
supply current to the device. The Melexis PTC hardware and software tools contain built in functions for reading the
EEPROM.
The MLX90251 can be programmed by using the PTC-04 programmer and the dedicated software tools. The timing and
voltage levels are controlled through the programming hardware and software. Further details can be found in the
MLX90251 software documentation.
14.3. Calibration Procedure
The programmable features of the device allow for calibration within the application. This section gives general
information for a two point calibration procedure. The two point calibration is the most common however, it is
possible to adapt other procedures.
1.) The first step in the calibration procedure is to initialize the device. This is done by establishing communication and
reading the contents of the EEPROM.
2.) The second step is to set the TempCo and FILTER settings.
3.) Step three is the evaluation of position one. During this step the output voltage is measured with initial values for
RG, FG and OFFSET.
4.) Step four is the evaluation of position two. During this step, the output voltage is measured with the same values
from step 3. From the measurements it is possible to calculate the slope and offset error. Next the output slope
transfer characteristic versus FG and RG is interpolated. With this information the initial settings are adjusted and the
output voltage is measured again.
5.) Step five is the final check and adjustment. At this stage small corrections are made to the OFFSET and FG
parameters. Next, the output clamping parameters, CLAMPHIGH and CLAMPLOW, are determined.
6.) The sixth step is the program phase. Now that all the parameters are determined and the application requirements
are satisfied, the settings are programmed into the EEPROM.
7.) The final step, seven, is the lock and verify step. Here the customer can perform any number of additional
measurements and verify the EEPROM contents. After this is completed the MEMLOCK is set and the EEPROM is
locked, preventing any further programming.
Note: EEPROM verification is done by reading the contents of the EEPROM and comparing it to the data written. It is
possible to read the EEPROM contents regardless of the status of MEMLOCK.
The Melexis PTC software tools contain built in functions and procedures for calibrating the MLX90251. Please refer to
the software documentation for more information on how to use the calibration tools.
The output of the MLX90251 is ratiometric. To avoid calibration errors from fluctuations in the supply voltage, the
output voltage should be measured as a percentage of the supply voltage.
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15. Standard information regarding manufacturability of Melexis
products with different soldering processes
Our products are classified and qualified regarding soldering technology, solder ability and moisture
sensitivity level according to standards in place in Semiconductor industry.
For further details about test method references and for compliance verification of selected soldering
method for product integration, Melexis recommends reviewing on our web site the General
Guidelines soldering recommendation. For all soldering technologies deviating from the one mentioned
in above document (regarding peak temperature, temperature gradient, temperature profile etc),
additional classification and qualification tests have to be agreed upon with Melexis.
For package technology embedding trim and form post-delivery capability, Melexis recommends to
consult the dedicated trim&form recommendation application note: lead trimming and forming
recommendations
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/en/quality-environment
16. 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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17. Package Information
VA-package: the lead-free VA-package is released for MSL1/245°C.
17.1. VA Package Outline and Hall Plate Position
VA Hall Plate / Chip Location
5.33
5.43
5.08
5.24
Hall Plate
0.24 x 0.24
4 5°
1.22
1.32
1.0X45o(REF)
0.387
0.289
3.76
3.86
4.10
4.50
5o
(2x)
5o
(2x)
4.14
4.30
3.30 3.63
3.46 3.79
45°
251F
123456
2.52
+/-0.15
1.10/1.20
0.61/0.66
0.24/0.29
2.10+/- 0.15
2.69
2.79
Notes:
0.25/0.35
0.51
nom.
0.0/0.1
1-All Nominal measurements in mm.
2-Mold & Package to lead frame off center
is 0.005 max. both horizental & vertical.
3-Molding Dimensions include end flash.
17.0
19.0
Front side marking :
Part Number MLX90251 (3 digits)
Die Version (1 digit)
251
F
123456
Lot number (6 digits)
Back side marking :
0.35
0.45
0.18
0.31
Year Date code (2 digits)
Week Date code (2 digits)
YY
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18. Contact
For the latest version of this document, go to our website at www.melexis.com.
For additional information, please contact our Direct Sales team and get help for your specific needs:
Europe, Africa
Telephone: +32 13 67 04 95
Email : sales_europe@melexis.com
Americas
Telephone: +1 603 223 2362
Email : sales_usa@melexis.com
Asia
Email : sales_asia@melexis.com
19. Disclaimer
The information furnished by Melexis herein (“Information”) is believed to be correct and accurate. Melexis disclaims (i) any and all liability in connection with or arising
out of the furnishing, performance or use of the technical data or use of the product(s) as described herein (“Product”) (ii) any and all liability, including without limitation,
special, consequential or incidental damages, and (iii) any and all warranties, express, statutory, implied, or by description, including warranties of fitness for particular
purpose, non-infringement and merchantability. No obligation or liability shall arise or flow out of Melexis’ rendering of technical or other services.
The Information is provided "as is” and Melexis reserves the right to change the Information at any time and without notice. Therefore, before placing orders and/or prior
to designing the Product into a system, users or any third party should obtain the latest version of the relevant information to verify that the information being relied upon
is current.
Users or any third party must further determine the suitability of the Product for its application, including the level of reliability required and determine whether it is fit for
a particular purpose.
The Information is proprietary and/or confidential information of Melexis and the use thereof or anything described by the Information does not grant, explicitly or
implicitly, to any party any patent rights, licenses, or any other intellectual property rights.
This document as well as the Product(s) may be subject to export control regulations. Please be aware that export might require a prior authorization from competent
authorities.
The Product(s) are intended for use in normal commercial applications. Unless otherwise agreed upon in writing, the Product(s) are not designed, authorized or warranted
to be suitable in applications requiring extended temperature range and/or unusual environmental requirements. High reliability applications, such as medical life-support
or life-sustaining equipment are specifically not recommended by Melexis.
The Product(s) may not be used for the following applications subject to export control regulations: the development, production, processing, operation, maintenance,
storage, recognition or proliferation of 1) chemical, biological or nuclear weapons, or for the development, production, maintenance or storage of missiles for such
weapons: 2) civil firearms, including spare parts or ammunition for such arms; 3) defense related products, or other material for military use or for law enforcement; 4) any
applications that, alone or in combination with other goods, substances or organisms could cause serious harm to persons or goods and that can be used as a means of
violence in an armed conflict or any similar violent situation.
The Products sold by Melexis are subject to the terms and conditions as specified in the Terms of Sale, which can be found at https://www.melexis.com/en/legal/termsand-conditions.
This document supersedes and replaces all prior information regarding the Product(s) and/or previous versions of this document.
Melexis NV © - No part of this document may be reproduced without the prior written consent of Melexis. (2016)
ISO/TS 16949 and ISO14001 Certified
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