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Электронный компонент: MLX90215L

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3901090215
Page 1
Aug/02
Rev 006
T
he 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 V
OQ
(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 V
OQ
stability drift of less than +0.4% error, over a broad
temperature range.
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
Linear Position Sensing
Rotary Position Sensing
Current Sensing
Part No.
Temperature Suffix
Package
MLX90215
L (-40C to 150C)
VA(4 Lead SIP)
MLX90215
E (-40C to 85C)
VA(4 Lead SIP)
Chopper
Shift Register (RAM)
OTPROM (ROM)
Program
Decoder
1
3
V
DD
2
4
D
A
C
D
A
C
D
A
C
Hall Plate
Pin 1 - V
DD
(Supply)
Pin 2 - Test/Readback Enable
Pin 3 - V
SS
(Ground)
Pin 4 - Output
Note: Static sensitive device, please observe ESD precautions.
3901090215
Page 2
Aug/02
Rev 006
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
Supply Voltage
V
DD
Operating
4.5
5.0
5.5
V
Supply Current
I
DD
B = 0, V
DD
= 5V, I
OUT
= 0
2.5
4.0
6.5
mA
Output Current
(1)
I
OUT
V
DD
= 5V + 10%
-2
-
2
mA
Quiescent Output Voltage
(2)
V
OQ
10-Bit Programmable, B = 0
0.5
-
4.5
V
Output Voltage
(1)
V
OH
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
-
s
Impulse Response Time
(6)
T
RMIN
RoughGain @ Max
250
s
Offset Voltage Adjustment
Resolution
V
OQ
B = 0, TA = 25
o
C
-1.5
-
1.5
mV
Offset Voltage Drift
over Temperature
V
OQ
/
T B = 0, TA = -40
o
C to 150
o
C
S < 100mV/mT & V
OQ
> 0.75V
-20
-
20
mV
Offset Voltage Drift
(2)
over Temperature
V
OQ
/
T B = 0, TA = -40
o
C to 150
o
C
S > 100mV/mT & V
OQ
< 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 = 25
o
C
-1
-
1
%
!"#$
DC Operating Parameters T
A
= -40
o
C to 150
o
C, V
DD
= 5.0V (Unless otherwise specified)
Output Voltage
(1)
V
OL
V
DD
= 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.
%
&
(1) If output current and voltage specifications are exceeded, linearity will be degraded.
2) If V
OQ
is programmed beyond these limits, the temperature compensation may become a problem at high
temperatures. It is not recommended to program values of V
OQ
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 independent of other parameters and does not include individual tolerances (
V
OQ
or
V
OQ
/
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
3901090215
Page 3
Aug/02
Rev 006
'
( )*
The MLX90215 programming is done through the
output pin, by changing supply voltage levels.
Please note that the V
DD
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 temporary 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
(V
OQ
)10 bits, 1024 steps of resolution, are allotted
to adjust the Quiescent Offset Voltage (V
OQ
). By
utilizing the HALFVDD function, the V
OQ
can be set
to one of two ranges. With the HALFVDD function
disabled, the V
OQ
can be programmed within a
range of 10% to 90% V
DD
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 device.
Units
HalfVDD
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 (V
OQ
)
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
3901090215
Page 4
Aug/02
Rev 006
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/
o
C 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/
o
C. 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 positive TC code.
TC Code
Min
Typical
Max
Units
0
-600
-450
-300
ppm/
o
C
1
-535
-385
-235
ppm/
o
C
2
-465
-315
-165
ppm/
o
C
3
-390
-240
-90
ppm/
o
C
4
-300
-150
0
ppm/
o
C
5
-235
-85
65
ppm/
o
C
6
-150
0
150
ppm/
o
C
7
-85
65
215
ppm/
o
C
8
125
275
425
ppm/
o
C
9
125
360
510
ppm/
o
C
10
210
435
585
ppm/
o
C
11
285
515
665
ppm/
o
C
12
450
600
750
ppm/
o
C
13
535
685
835
ppm/
o
C
14
600
750
900
ppm/
o
C
15
680
830
980
ppm/
o
C
16
1150
1300
1450
ppm/
o
C
17
1230
1380
1530
ppm/
o
C
18
1320
1470
1620
ppm/
o
C
19
1405
1555
1705
ppm/
o
C
20
1490
1640
1790
ppm/
o
C
21
1575
1725
1875
ppm/
o
C
22
1665
1815
1965
ppm/
o
C
23
1750
1900
2950
ppm/
o
C
24
2165
2365
2565
ppm/
o
C
25
2340
2490
2640
ppm/
o
C
26
2425
2575
2725
ppm/
o
C
27
2500
2650
2800
ppm/
o
C
28
2595
2745
2895
ppm/
o
C
29
2680
2830
2980
ppm/
o
C
30
2710
2910
3110
ppm/
o
C
31
2775
2975
3175
ppm/
o
C
Table 3 - Temperature Compensation
(Reference Only)
Condition
Output Level
V
OUT
Shorted to V
DD
V
OUT
= V
DD
V
OUT
Shorted to V
SS

V
OUT
= V
SS
V
OUT
open with pull up load
V
OUT
= V
DD
V
OUT
open with pull down load
V
OUT
= V
SS
V
SS
open with pull up load
V
OUT
= V
DD
V
SS
open with pull down load
> 10 K Ohms
V
OUT
= V
DD
or 94% V
DD
V
DD
open with pull up load
> 4.7 K Ohms
V
OUT
= V
SS
or 3% V
DD
V
DD
open with pull down load
V
OUT
= V
SS
Temperature Compensation
Temperature compensation (TC) is defined as the
change in sensitivity over temperature. Expressed
in (Parts Per Million per Degree Celcius) ppm/
o
C.
Sens
T1
= Sensitivity measured at Temp.1 (T1)
Sens
T2
= Sensitivity measured at Temp.2 (T2)
Sens
25
= Initial Sensitivity measured at 25
o
C
C
ppm
T
T
Sens
Sens
Sens
TC
o
T
T
6
25
2
1
10
2
1
1
-
-
=
3901090215
Page 5
Aug/02
Rev 006
5
4
3
2
1
0
0
-
6
-
1
2
-
1
8
6
1
2
1
8
O
u
t
p
u
t

V
o
l
t
a
g
e

(
V
)
Flux Density (mT)
Typical Output Voltage versus
Magnetic Flux Density
Sensitivity = 140mV/mT
MLX90215
5
4
3
2
1
0
0
-
9
0
-
1
8
0
-
2
7
0
9
0
1
8
0
2
7
0
O
u
t
p
u
t

V
o
l
t
a
g
e

(
V
)
Flux Density (mT)
Typical Output Voltage versus
Magnetic Flux Density
Sensitivity = 10mV/mT
MLX90215
!"#$