Datasheet MLX90215L, MLX90215E Datasheet (MELEXIS)

Page 1
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 1
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
Description
The MLX90215 is a Programmable Linear Hall Effect sensor IC fabricated utilizing silicon-CMOS technology. It possesses active error correction circuitry which virtually eliminates the offset errors normally associated with analog Hall Effect devices. All magnetic response functions of the MLX90215 are fully programmable for even greater versatility. The VOQ (V
OUT
@ B=0), sensitivity, direction of slope and the magnitude of sensitivity drift over temperature, are all programmable.
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 will not affect accuracy. When programmed for a conventional sensitivity (with a positive gain) , the voltage at the output will increase as a South magnetic field is applied to the branded face of the MLX90215. Conversely, the voltage output will decrease in the presence of a North magnetic field. The MLX90215 has a sensitivity drift of less than +1% error, and VOQ stability drift of less than +0.4% error, over a broad temperature range.
Functional Diagram
Features and Benefits
Programmable Linear Hall IC
Quad Switched / Chopper Stabilized
Ratiometric Output for A/D Interface
Adjustable Quiescent Voltage (V
OQ
)
Very Low Quiescent Voltage Temperature Drift
Adjustable Sensitivity
Adjustable Temperature Compensation of Sensitivity
Applications
Linear Position Sensing
Rotary Position Sensing
Current Sensing
Ordering Information
Part No. Temperature Suffix Package Temperature Range
MLX90215 L VA(4 Lead SIP) -40°C to 150°C MLX90215 E VA(4 Lead SIP) -40°C to 85°C
Chopper
Shift Register (RAM)
OTPROM (ROM)
Program Decoder
1
3
V
DD
2
4
DAC
DAC
DAC
Hall Plate
Pin 1 - VDD (Supply) Pin 2 - Test/Readback Enable Pin 3 - VSS (Ground) Pin 4 - Output
Note: Static sensitive device, please observe ESD precautions.
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*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 2
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
Parameter Symbol Test Conditions Min Typ Max Units
Supply Voltage VDD Operating 4.5 5.0 5.5 V Supply Current IDD B = 0, VDD = 5V, I
OUT
= 0 2.5 4.0 6.5 mA
Output Current
(1)
I
OUT
VDD = 5V + 10% -2 - 2 mA
Quiescent Output Voltage
(2)
VOQ 10-Bit Programmable, B = 0 0.5 - 4.5 V
Output Voltage
(1)
VOH V
DD
= 5V, I
OUT
= -2mA 4.50 4.65 V
Bandwidth
(3)
BW RoughGain @ Min - 1.300 kHz
Bandwidth
(3)
BW RoughGain @ Max 0.130 - kHz
Impulse Response Time
(6)
T
RMIN
RoughGain @ Min 25 - µs
Impulse Response Time
(6)
T
RMIN
RoughGain @ Max 250 µs
Offset Voltage Adjustment Resolution
VOQ B = 0, TA = 25oC -1.5 - 1.5 mV
Offset Voltage Drift over Temperature
VOQ/T B = 0, TA = -40oC to 150oC
S < 100mV/mT & VOQ > 0.75V
-20 - 20 mV
Offset Voltage Drift
(2)
over Temperature
VOQ/T B = 0, TA = -40oC to 150oC
S > 100mV/mT & VOQ < 0.75V
-40 - 40 mV
Range of Sensitivity
(7)
s 13-Bit Programmable 5 - 140 mV/mT
Peak to Peak Noise
(4)
8 25 60 mV
Output Resistance R
OUT
6
Sensitivity Drift
(5)
TA = 25oC -1 - 1 %
MLX90215 Electrical Specifications
Output Voltage
(1)
VOL VDD = 5V, I
OUT
= 2mA 0.35 0.50 V
Sampling Rate f
SAMP
RoughGain @ Max and Min 4 - 40 kHz
Melexis Inc. reserves the right to make changes without further notice to any products herein to improve reliability, function, or design. Melexis does not assume any liability arising from the use of any product or application of any product or circuit described herein.
Notes:
(1) If output current and voltage specifications are exceeded, linearity will be degraded. (2) If VOQ is programmed beyond these limits, the temperature compensation may become a problem at high tem­peratures. It is not recommended to program values of VOQ below 1V or above 4V when sensitivity exceeds 100 mV/mT. Temperature instability can occur on some devices under these conditions. (3) Bandwidth is inversely proportional to ROUGHGAIN. (4) Peak to Peak Noise is a function of ROUGHGAIN setting. See page 5, Peak to Peak Noise versus Sensitivity. (5) Sensitivity drift is indepe ndent of other parameters and does not include individual tolerances (V
OQ
or VOQ/T). The tolerance for sensitivity is + 1% of its initial value. This does not include tolerance stack-up. (6) If the impulse occurs in the middle of a sample interval, the small signal response delay will double. If a 50% to 100% impulse, slew rate may result in double or triple delay. (7) 1 mT = 10 Gauss
Page 3
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 3
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
How does it Work?
The MLX90215 programming is done through the output pin, by changing supply voltage levels. Please note that the VDD is raised to approximately 13V and 18V during programming. Any connected
components must also tolerate this voltage excursion. When the supply voltage is at 4.5V to
5.5V, the output behaves normally. If the supply voltage is raised to 13V, the output then behaves as an input, or LOAD mode, allowing the 31 -bit word to be clocked in. All data is loaded through a single line, with no dedicated clock signal. Clock and data are integrated into one signal which is initiated with the beginning of the LOAD sequence, then clocked with the positive edge of each bit. Variables are changed with the PC software and loaded into the te mporary register of the device (RAM) via the timings of the programmer’s microcontroller. Data can be loaded as many times as desired while in LOAD mode. Once a word is loaded, results are checked by observing the output voltage. This can be done with an external Voltmeter attached directly to pin 4 of the device, or with the internal ADC of the programmer. Once the desired program is loaded, the word can be “Zapped” permanently into ROM. This is done when the supply voltage rises above 18V, or ZAP mode, creating enough current to “Zap” 31 zener diodes which correspond to the temporary register. The ZAP function is a one-time function and cannot be erased. The above description is only for reference. The voltage levels and data transfer rates are completely controlled by the ASIC programmer. For more information on the programmer hardware, contact Melexis and request a datasheet for the SDAP programmer.
Programming The Quiescent Offset Voltage (VOQ)
10 bits, 1024 steps of resolution, are allotted to adjust the Quiescent Offset Voltage (VOQ). By utilizing the
HALFVDD function, the VOQ can be set to one of two ranges. With the HALFVDD function disabled, the VOQ can be programmed within a range of 10% to 90% VDD with about 5mV per step resolution. With the HALFVDD function enabled, the device may be programmed within a 2V to 3V window with less than 1mV per step resolution
Programming the Sensitivity (Gain) The sensitivity is programmed with a ROUGHGAIN and a FINEGAIN adjustment. The ROUGHGAIN is adjusted by utilizing three bits, or 8 increments. The FINEGAIN is programmed with 10 bits or 1024 increments. The sensitivity can be programmed within a range of 5mV/mT to 140mV/mT. Another 1-bit function allows the direction of the sensitivity to be reversed. The INVERTSLOPE function, when activated, will cause the Voltage output of the MLX90215 to decrease in the presence of a South magnetic field, and to increase in the presence of a North magnetic field. Table 2 expresses examples of sensitivity resulting from programming ROUGH GAIN and FINE GAIN codes, with the INVERT SLOPE function turned off.
Note: Tables 1 and 2 are examples how various codes affect the
UnitsHalfVDD OffsetDAC Output 0 0 0 1 1 1
0
512
1023
0
512
1023
4.97
2.47
0.03
3.07
2.45
1.83
V V V V V V
Table 1 - Programming Offset Voltage (VOQ)
RoughGain FineGain Output Units
0 0 1 1 2 2
0
1023
1023
0
4.1
9.4
6.2
14.6
9.5
22.4
mV/mT
Table 2 - Programming Sensitivity
mV/mT mV/mT mV/mT mV/mT
mV/mT 3 3 4 4 5 5
0
1023
1023
0
14.2
33.1
21.5
50.4
31.3
72.5
mV/mT
mV/mT
mV/mT
mV/mT
mV/mT
mV/mT 6 6
46.2 107
mV/mT
mV/mT 7 7
68.9 140
mV/mT mV/mT
0
1023
0
1023
0
1023
0
1023
Page 4
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 4
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
Programming the Temperature Compensation The MLX90215 has a 5-bit (32 step) programmable adjustment that changes it’s sensitivity drift over a given temperature range. By adjusting the TC code the sensitivity can be programmed to increase as temperature increases to counteract the decrease in magnetic flux most magnets display over temperature. For example a SmCo (Samarium Cobalt) magnet has a temperature coefficient of approximately –300 ppm/
o
C. The MLX90215 can be programmed with a TC of 300 ppm/oC to counteract the TC of the magnet and greatly improve linearity over temperature.
Table 3 (left) illustrates the way the TC code affects the sensitivity temperature drift. Also note in Table 3, the overlap in TC codes. The numbers in the table represent typical results and are for reference only. For accurate results the TC code must be determined experimentally. This Tc code map applies to MLX90215’s with a second line brand showing “15DXX”
Special Note
The MLX90215 programmed with a zero TC code (default) has a typical TC value between the range of – 300 to –600 ppm/oC. This means sensitivity will decrease slightly as temperature increases. The slightly negative initial TC value allows the MLX90215 to be accurately programmed up to 0 TC. Almost all magnets have a naturally negative TC code. The natural TC of a magnet added with the initial negative TC value of the MLX90215 could degrade linearity over a large temperature span. Using a TC code of 6, 7, or 8 will give the MLX90215 a slightly posit ive TC code.
Early revisions of the MLX90215 with second line brand of “15AXX” should refer to factory for Tc code
TC Code Min Typical Max Units
0 -600 -450 -300 ppm/oC 1 -535 -385 -235 ppm/oC 2 -465 -315 -165 ppm/oC 3 -390 -240 -90 ppm/oC 4 -300 -150 0 ppm/oC 5 -235 -85 65 ppm/oC 6 -150 0 150 ppm/oC 7 -85 65 215 ppm/oC 8 125 275 425 ppm/oC
9 125 360 510 ppm/oC 10 210 435 585 ppm/oC 11 285 515 665 ppm/oC 12 450 600 750 ppm/oC 13 535 685 835 ppm/oC 14 600 750 900 ppm/oC 15 680 830 980 ppm/oC 16 1150 1300 1450 ppm/oC 17 1230 1380 1530 ppm/oC 18 1320 1470 1620 ppm/oC 19 1405 1555 1705 ppm/oC 20 1490 1640 1790 ppm/oC 21 1575 1725 1875 ppm/oC 22 1665 1815 1965 ppm/oC 23 1750 1900 2950 ppm/oC 24 2165 2365 2565 ppm/oC 25 2340 2490 2640 ppm/oC 26 2425 2575 2725 ppm/oC 27 2500 2650 2800 ppm/oC 28 2595 2745 2895 ppm/oC 29 2680 2830 2980 ppm/oC 30 2710 2910 3110 ppm/oC 31 2775 2975 3175 ppm/oC
Table 3 - Temperature Compensation
Condition Output Level
V
OUT
Shorted to VDD V
OUT
= VDD
V
OUT
Shorted to VSS V
OUT
= VSS
V
OUT
open with pull up load V
OUT
= VDD
V
OUT
open with pull down load V
OUT
= VSS
VSS open with pull up load V
OUT
= VDD
VSS open with pull down load > 10 K Ohms
V
OUT
= VDD
or 94% VDD
VDD open with pull up load > 4.7 K Ohms
V
OUT
= VSS
or 3% VDD
VDD open with pull down load V
OUT
= VSS
Temperature Compensation Temperature compensation (TC) is defined as the change in sensitivity over temperature. Expressed in (Parts Per Million per Degree Celcius) ppm/oC.
SensT1 = Sensitivity measured at Temperature 1 (T1) SensT2 = Sensitivity measured at Temperature 2 (T2) Sens25 = Initial Sensitivity measured at 25oC
C
ppm
TTSens
SensSens
TC
o
TT
6
25
21
10
21
1
=
Page 5
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 5
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
5
4
3
2
1
0
0
-6
-12
-18
6
12
18
Output Voltage (V)
Flux Density (mT)
Typical Output Voltage versus Magnetic Flux Density Sensitivity = 140mV/mT
MLX90215
5
4
3
2
1
0
0
-90
-180
-270
90
180
270
Output Voltage (V)
Flux Density (mT)
Typical Output Voltage versus Magnetic Flux Density Sensitivity = 10mV/mT
MLX90215
32.7
25.4
18.1
10.8
3.5 3210 4 5 6
Sample Rate (kHz)
RoughGain (PA) Value
Typical Sample Rate versus Rough Gain (PA)
MLX90215
7
40
50
40
30
20
10
0
65
40
15
5
90
115
140
Output Voltage (mV)
Sensitivity (mV/mT)
Typical Peak to Peak Noise versus Sensitivity
60
MLX90215
MLX90215 Performance
Page 6
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 6
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
.
Supply Voltage (Over Voltage) 18V Supply Voltage (Operating) 5V + 10% Reverse Voltage Protection -14.5V Magnetic Flux Density Unlimited Supply Current, IDD 6.5 mA Output Current (Short to VDD) +12 mA Output Current (Short to VSS) -12 mA Operating Temperature Range, TA -40°C to 150°C Storage Temperature Range, TS -55°C to 165°C ESD Sensitivity +7kV
Absolute Maximum Ratings
Pin Description
Recommended Wiring
MLX
90215
V
DD
1 2 3 4
C1 C2
Pin1 V
DD
Pin2 Test* Pin3 V
SS
Pin4 OUT
C1 = 2.5nF C2 = 2.5nF Mutilayer surface mount capacitors recommended
*Readback diagnostic use only. Pin 2 is NOT for programming device. For best results, tie to GND.
Melexis Programmer
Melexis offers a programmer (PTC-01) for progra m­ming the MLX90215. The PTC-01 comes complete with windows based software that makes programming the MLX90215 simple. The programmer communi­cates with a PC via a RS232 serial interface. The pro­grammer and software allows users to load settings in the MLX90215, take measurements, calibrate sensors, and program the MLX90215. For more information the PTC-01 goto www.melexis.com, or contact Melexis.
Left, PTC -01 windows based software. Works with any IBM compatible PC run­ning windows 9x.
Melexis PTC-01 Programmer
Page 7
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 7
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
Clamping the Output Voltage
The MLX90215 has a 2-bit CLAMP feature which allows Four output voltage options. The CLAMP fe a­ture is independent of the gain, and will not effect se n­sitivity of the device. The table below illustrates limits for each of the four options.
Bit Value Limits (% VDD) 0 (default)) no clamp 1 5 to 45 2 10 to 90 3 5 to 95
Application Comments
The following is a list of recommended operating pa­rameters that will help to ensure the accuracy and sta­bility of the MLX90215. These are not the absolute programming limits of the device.
1.) Voq is best programmed in the absence of any magnetic influence and to voltages closest to 1/2 VDD, where temperature drift will be +/-0.4% or less. It is not recommended to use VOQ values close to 0 volts or VDD when programming extremely high sensitivity (> 100 mV/mT) values. Tempera ­ ture instability may be observed on some devices under these conditions.
2.) Best linearity of sensitivity is obtained when VOQ is programmed at 1/2 VDD. This is with the 1/2 VDD function enabled.
3.) Best linearity of sensitivity is obtained when the gain is programmed between 5mV/mT and 100mV/mT.
4.) Best temperature stability is realized when the temperature compensation function is programmed to zero ppm/oC.
5.) The Test/Readback pin is for diagnostic use only. This pin is normally tied to GND. Contact Melexis for more details on programming this device.
Installation Comments
1.) Avoid mechanical stress on leads or package. Stress may cause VOQ shift. A.) Avoid bending leads at the package interface. B.) Support the leads by clamping, when bend ing. C.) Avoid gluing device to another material. This may cause temperature-related stress.
2.) CMOS products are static sensitive devices, please observe ESD precautions.
3.) Observe temperature limits during soldering.
Bit Allocation Table
Bit Function
1 INVERTSLOPE 2 OFFSETDAC 5 3 OFFSETDAC 6 4 OFFSETDAC 7 5 OFFSETDAC 8 6 OFFSETDAC 9 7 OFFSETDAC 4 8 OFFSETDAC 3
9 OFFSETDAC 2 10 OFFSETDAC 1 11 OFFSETDAC 0 12 FINEGAIN 0 13 FINEGAIN 1 14 FINEGAIN 2 15 HALFVDD 16 FINEGAIN 3 17 FINEGAIN 4 18 FINEGAIN 5 19 FINEGAIN 8 20 FINEGAIN 9
22 FINEGAIN 7 23 ROUGHGAIN 2 24 ROUGHGAIN 1 25 ROUGHGAIN 0 26 TEMP CO 0 27 TEMP CO 1 28 TEMP CO 2 29 TEMP CO 3 30 TEMP CO 4 31 CLAMP 1 32 CLAMP 0 33 MEMLOCK 34 TEST 0 35 TEST 1 36 TEST 2 37 TEST 3
21 FINEGAIN 6
Page 8
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 8
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
Physical Characteristics
All Dimensions in millimeters
VA Hall Plate / Chip Location
VA Package Dimensions
Notes:
1. Pinout: Pin 1 V
DD
Pin 2 Test/Readback Pin 3 GND Pin 4 Output
2. Controlling dimension: mm .
3. Leads must be free of flash and plating voids.
4. Leads must not arc toward the rear of package.
5. VA lead frame material: C151.
6. VA molding compound: Sumitomo EME 6300H.
7. Package dimensions exclude molding flash.
8. Tolerance: +/- 0.254 mm unless otherwise specified.
9
. *Marking: Line 1: 1st and 2nd digits (00) = Year (2000) 3rd and 4th digits (14) = Week of Year
Line 2: 1st and 2nd digits (15) = Chip I.D. (90215) 3rd digit (D) = Chip Revision 4th and 5th digits(88) = Lot Number
2.86
1.86
2.18
Hall Plate
0.20 x
0.20
2.69
0.387
0.289
Marked
Surface
E
3.46
3.30
A B C
5
o
(2x)
5
o
(2x)
0.387
0.289
3.79
3.63
D
F G
H
1.0 MA
X
0.22
REF
0.45
0.35
4.50
4.10
45o X 1mm
15.50
14.50
0014
15D88
*
1 2 3
4
5.08
5.24
5.33
5.43
1.22
1.32 3.76
3.86
J
VA
1.20
1.10
0.66
0.61
0.29
0.24
45
o
0.31
0.18
B
A
C D E
0.15
0.0
F G H
0.60
0.40
0.35
0.25
J
45
o
For the latest version of this document, Go to our Website at:
WWW.Melexis.Com
For additional information Contact Melexis direct at: Europe and Japan USA and Rest of World E-mail: sales_europe@melexis.com Sales_usa@melexis.com Phone: 011-32-13-670-780 (603) 223-2362
Page 9
*Patent Pending
MLX90215 Programmable Hall Effect Sensor Rev 4.3 7/6/01 Page 9
MLX90215
Precision Programmable*
Linear Hall Effect Sensor
Application Notes
5 4 3 2 1 0
0-100 100
Current (Amps)
V
OUT
(Volts)
MLX
90215
V
DD
A slotted ferrite toroidal core and a series of windings are the main elements of a current sensor. By adding a programmable Hall IC to the air gap, not only can the output be calibrated accurately, but it can also be adjusted to respond to virtually any range of current
Programmable Current Sensor
Linear Precision Current Sensor
The Programmable gain, offset, and temperature co m­pensation of MLX90215 allows great flexiblity in the design of a current sensor. Current flowing through a conductor can produce a proportional magnet field. The MLX90215 can then produce an output voltage proportional to the current. Using the programmable gain and offset function the output of the MLX90215 can be adjusted to sense a wide range of current allowing for a flexible design.
Slotted Torroid Example Assuming infinite perme­abilty of the core, the magnetic field through the air gap produced by a single wire turn is given by equ a­tion 2
Equation 2
Where: I = current in Amperes B = magnetic field in Tesla lg = length of air gap in Meters uo = Permeabili ty of free space (4π10-7H/m)
This equation is a close estimate for the field in the air gap, but does not take into account magnetic losses in the core, fringing effects, and mechanical tolerances of the air gap. The programmable MLX90215 can be adjusted to compensate for these errors simplifying the design. The temperature compensation of MLX90215 can also be adjusted to counteract temperature losses of core.
For sensing a current ±100A, with an air gap of 2mm equation 2 yields a magnetic field range of ±63mT. The output range of the MLX90215 is 0.5V to 4.5V (4V full scale). Equations 3a and 3b yield a sensitivity of 32mV/mT and a Voq of 2.5V.
Equation 3
a) S = 4000mV/ 126mT b) Voq = 4V/2 + 0.5V The resulting gain of the current sensor is 20mV/A with an offset of 2.5V. For best results it is recommend that MLX90215 be programmed with a Voq of 50% Vdd 1/2 Vdd bit set.
o
g
u
l
I
B =
Magnetic Suppliers
Elna Ferrites Technologies Inc
Eastern Components
Fair Rite Products Corp
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