View TLE4921-3U_185369.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

Dynamic Differential Hall Effect Sensor IC
TLE 4921-3U
Bipolar IC Features * * * * * * * * * * * * * * * Advanced performance High sensitivity Symmetrical thresholds High piezo resistivity Reduced power consumption South and north pole pre-induction possible AC coupled Digital output signal Two-wire and three-wire configuration possible Large temperature range Large airgap Low cut-off frequency Protection against overvoltage Protection against reversed polarity Output protection against electrical disturbances
P-SSO-4-1
Type TLE 4921-3U
Ordering Code Q67006-A9171
Package P-SSO-4-1
The differential Hall Effect sensor TLE 4921-3U provides a high sensitivity and a superior stability over temperature and symmetrical thresholds in order to achieve a stable duty cycle. TLE 4921-3U is particularly suitable for rotational speed detection and timing applications of ferromagnetic toothed wheels such as anti-lock braking systems, transmissions, crankshafts, etc. The integrated circuit (based on Hall effect) provides a digital signal output with frequency proportional to the speed of rotation. Unlike other rotational sensors differential Hall ICs are not influenced by radial vibration within the effective airgap of the sensor and require no external signal processing.
Semiconductor Group
1
1998-07-31
TLE 4921-3U
Pin Configuration (view on branded side of component)
2.67
1.53
Center of sensitive area 0.15
2.5 1 2 3 4
VS
Q GND C
AEP01694
Figure 1
Pin Definitions and Functions Pin No. 1 2 3 4 Symbol Function Supply voltage Output Ground Capacitor
VS
Q GND
C
Semiconductor Group
2
1998-07-31
TLE 4921-3U
VS
1
Protection Device
Internal Reference and Supply
Vreg (3V)
Hall-Probes HighpassFilter SchmittTrigger Open Collector Protection Device
Amplifier
2
Q
3 GND
4
CF
AEB01695
Figure 2
Block Diagram
Semiconductor Group
3
1998-07-31
TLE 4921-3U
Functional Description The Differential Hall Sensor IC detects the motion and position of ferromagnetic and permanent magnet structures by measuring the differential flux density of the magnetic field. To detect ferromagnetic objects the magnetic field must be provided by a back biasing permanent magnet (south or north pole of the magnet attached to the rear unmarked side of the IC package). Using an external capacitor the generated Hall voltage signal is slowly adjusted via an active high pass filter with a low cut-off frequency. This causes the output to switch into a biased mode after a time constant is elapsed. The time constant is determined by the external capacitor. Filtering avoids aging and temperature influence from Schmitt-trigger input and eliminates device and magnetic offset. The TLE 4921-3U can be exploited to detect toothed wheel rotation in a rough environment. Jolts against the toothed wheel and ripple have no influence on the output signal. Furthermore, the TLE 4921-3U can be operated in a two-wire as well as in a three-wireconfiguration. The output is logic compatible by high/low levels regarding on and off. Circuit Description (see figure 2) The TLE 4921-3U is comprised of a supply voltage reference, a pair of Hall probes spaced at 2.5 mm, differential amplifier, filter for offset compensation, Schmitt trigger, and an open collector output. The TLE 4921-3U was designed to have a wide range of application parameter variations. Differential fields up to 80 mT can be detected without influence to the switching performance. The pre-induction field can either come from a magnetic south or north pole, whereby the field strength up to 500 mT or more will not influence the switching points. The improved temperature compensation enables a superior sensitivity and accuracy over the temperature range. Finally the optimized piezo compensation and the integrated dynamic offset compensation enable easy manufacturing and elimination of magnet offsets. Protection is provided at the input/supply (pin 1) for overvoltage and reverse polarity and against overstress such as load dump, etc., in accordance with ISO-TR 7637 and DIN 40839. The output (pin 2) is protected against voltage peaks and electrical disturbances.
Semiconductor Group
4
1998-07-31
TLE 4921-3U
Absolute Maximum Ratings Tj = - 40 to 150 C Parameter Supply voltage Output voltage Output current Output reverse current Capacitor voltage Junction temperature Junction temperature Junction temperature Junction temperature Storage temperature Thermal resistance P-SSO-4-1 Current through inputprotection device Current through outputprotection device Symbol Limit Values min. max. 30 30 50 50 - 0.3 3 150 160 170 210 - 40 150 190 200 200 V V mA mA V C C C C C K/W mA mA 5000 h 2500 h 1000 h 40 h - 35
1)
Unit
Remarks
VS VQ IQ - IQ VC Tj Tj Tj Tj TS Rth JA ISZ IQZ
- 0.7
t < 2 ms; v = 0.1 t < 2 ms; v = 0.1
Electro Magnetic Compatibility ref. DIN 40839 part 1; test circuit 1 Testpulse 1 Testpulse 2 Testpulse 3a Testpulse 3b Testpulse 4 Testpulse 5
1)
VLD VLD VLD VLD VLD VLD
- 100 100 - 150 100 -7 120
V V V V V V
td = 2 ms td = 0.05 ms td = 0.1 s td = 0.1 s td 20 s td = 400 ms; RP = 400
Reverse current < 10 mA
Note: Stresses above those listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Semiconductor Group
5
1998-07-31
TLE 4921-3U
Operating Range Parameter Supply voltage Junction temperature Pre-induction Symbol Limit Values min. max. 24 170 500 V C mT at Hall probe; independent of magnet orientation 4.5 - 40 - 500 Unit Remarks
VS Tj B0
B
Differential induction
- 80
80
mT
Note: In the operating range the functions given in the circuit description are fulfilled.
AC/DC Characteristics Parameter Supply current Symbol Limit Values min. typ. max. 6.1 6.7 8.0 8.8 mA mA V A mT 4.7 5.1 Output saturation voltage Output leakage current Center of switching points: (BOP + BRP) / 2 Operate point Release point Hysteresis Unit Test Condition Test Circuit 1 1 1 1 2
IS
VQSat IQL
Bm -1
0.25 0.6 10 0 1
VQ = high IQ = 0 mA VQ = low IQ = 40 mA IQ = 40 mA VQ = 24 V
- 20 mT < B < 20 mT 1) 2) f = 200 Hz B = 20 mT
BOP BRP BHy 0 0.5 1.5
0
mT mT
f = 200 Hz, f = 200 Hz,
2 2 2
B = 20 mT 2.5 mT
f = 200 Hz,
B = 20 mT 1 1
Overvoltage protection at supply VSZ voltage at output VQZ
27 27
35 35
V V
IS = 16 mA IS = 16 mA
Semiconductor Group
6
1998-07-31
TLE 4921-3U
AC/DC Characteristics (cont'd) Parameter Output rise time Output fall time Delay time3) Symbol Limit Values min. typ. max. 0.5 0.5 25 10 15 48 s s s s s k mV/ mT 2.2 0.1 0.1 V mT mT B = 0 B = 5 mT F=2N 20000 Hz Unit Test Condition Test Circuit 1 1 2
tr tf tdop tdrp tdop - tdrp RC 32 SC VC f
Bm BHy 0.8
4)
IQ = 40 mA CL = 10 pF IQ = 40 mA CL = 10 pF f = 10 kHz
B = 5 mT
0 40 -4
Filter input resistance Filter sensitivity to B Filter bias voltage Frequency Resistivity against mechanical stress (piezo)
1)
25 C 2 C
1 1 1 2 25)
- 0.1 - 0.1
Leakage currents at pin 4 should be avoided. The bias shift of Bm caused by a leakage current IL can be 1 calculated by: B m = ------------------------------------------------- . SC ( T ) x I L x RC ( T )
2) 3) 4)
For higher B the values may exceed the limits like following | Bm | < | 0.05 x B | For definition see page 16. 1 Depends on filter capacitor CF. The cut-off frequency is given by f = ---------------------------------- . The switching points are 2 x R C x C F guaranteed over the whole frequency range, but amplitude modification and phase shift due to the 1st order highpass filter have to be taken into account.
5)
See page 17.
Note: The listed characteristics are ensured over the operating range of the integrated circuit. Typical characteristics specify mean values expected over the production spread. If not otherwise specified, typical characteristics apply at Tj = 25 C and the given supply voltage.
Semiconductor Group
7
1998-07-31
TLE 4921-3U
RP
300
V SZ
1
S
VS RL
VLD
4.7 nF
VS
C
1)
4
C
Q
2
Q , QR
VC
GND 3
V QSat , V QZ
CL
1)
RC =
VC C
AES01696
Figure 3
Test Circuit 1
1
VS
1 k 2 f min f max B OP B Hy
AES01258
VS
4
C
Q
VQ
CF
470 nF GND 3
Figure 4
Test Circuit 2
Semiconductor Group
8
1998-07-31
TLE 4921-3U
Application Configurations Two possible applications are shown in figure 7 and 8 (Toothed and Magnet Wheel). The difference between two-wire and three-wire application is shown in figure 9. Gear Tooth Sensing In the case of ferromagnetic toothed wheel application the IC has to be biased by the south or north pole of a permanent magnet (e.g. SmCO5 (Vacuumschmelze VX145) with the dimensions 8 mm x 5 mm x 3 mm) which should cover both Hall probes. The maximum air gap depends on - the magnetic field strength (magnet used; pre-induction) and - the toothed wheel that is used (dimensions, material, etc.; resulting differential field) a centered distance of Hall probes b Hall probes to IC surface L IC surface to tooth wheel
L
N S b a
a = 2.5 mm b = 0.3 mm
AEA01259
Figure 5
Sensor Spacing
T
Conversion DIN - ASA
m = 25.4 mm/p T = 25.4 mm CP
AEA01260
d
DIN
d z m T
ASA diameter (mm) number of teeth module m = d/z (mm) pitch T = x m (mm) Toothed Wheel Dimensions
p
diameter pitch p circular pitch
= z/d (inch)
PD CP
pitch diameter PD = z/p (inch) CP = 1 inch x /p
Figure 6
Semiconductor Group
9
1998-07-31
TLE 4921-3U
Gear Wheel
Hall Sensor 1
Hall Sensor 2
Signal Processing Circuitry
S (N) N (S)
Permanent Magnet
AEA01261
Figure 7
TLE 4921-3U, with Ferromagnetic Toothed Wheel
Magnet Wheel
S N
Hall Sensor 1
S
Hall Sensor 2
Signal Processing Circuitry
AEA01262
Figure 8
TLE 4921-3U, with Magnet Wheel
10 1998-07-31
Semiconductor Group
TLE 4921-3U
Two-wire-application Line 1 VS C GND 3 Q
VS
RL
2
4
CF 470 nF
VSIGNAL RS
Sensor for example : R L = 330 R S = 120
Mainframe
AES01263
Three-wire-application
Rp
1 VS C GND 3 Q
Line
VS RL
4
2 4.7 nF 4.7 nF
VSIGNAL
CF 470 nF
Sensor for example : R L = 330 R P = 0 ... 330
Mainframe
AES01264
Figure 9
Application Circuits
Semiconductor Group
11
1998-07-31
TLE 4921-3U
N (S) S (N) 1 B1 Wheel Profile B2 Missing Tooth 4
Magnetic Field Difference B = B2-B1
Small Airgap Large Airgap B RP = 0.75 mT B HYS
B OP = -0.75 mT
Output Signal VQ
Operate point : B2 - B1 < B OP switches the output ON (VQ = LOW) Release point : B2 - B1 > B RP switches the output OFF (VQ = HIGH) B RP = BOP + B HYS The magnetic field is defined as positive if the south pole of the magnet shows towards the rear side of the IC housing.
AED01697
Figure 10 System Operation
Semiconductor Group
12
1998-07-31
TLE 4921-3U
Quiescent Current versus Supply Voltage
10.0
AED01698
Quiescent Current versus Temperature
10.0
AED01699
S
mA 7.5
Q ON = 40 mA S ON S OFF
S
mA 7.5
Q ON = 40 mA
S ON S OFF
5.0
5.0
2.5
2.5
S diff
0 0 5 10 15 V 25
0 -50
0
50
100
C
200
VS
Ta
Quiescent Current Difference versus Temperature
1.0 S mA 0.75
AED01700
Quiescent Current versus Output Current
10.0
AED01701
S
Q ON = 40 mA
mA 7.5
VS = 12 V
S ON - S OFF
0.5
S ON
5.0
0.25
2.5
0
0
5
10
15
V
25
0
0
10
20
30
mA
50
VS
Q
Semiconductor Group
13
1998-07-31
TLE 4921-3U
Saturation Voltage versus Temperature
AED01702
Saturation Voltage versus Output Current
0.3
AED01703
0.4
VQ
V 0.3
VS = 4.5 V Q = 50 mA
VQ
V 0.2 0.1 0
Ta = 25 C
0.2
-0.1 -0.2 -0.3
0 -50
0.1
0
50
100
C
200
-0.4 -50
-30
-10
10
30 mA 50
Ta
Q
Saturation Voltage versus Supply Voltage
0.4
AED01704
Switching Points versus Preinduction
AED01705
2.0 mT 1.5 -80 mT < B < 80 mT
VQ
V 0.3
Q = 40 mA Ta = 25 C
BRP, (-B OP )
0.2
1.0 typ
0.1
0.5
0
0
5
10
15
V
25
0 -500
-250
0
mT
500
VS
BO
Semiconductor Group
14
1998-07-31
TLE 4921-3U
Switching Induction versus Temperature
2
AED01706
Hysteresis versus Temperature
AED01707
3.5
Bm
mT 1
B m = ( B OP +B RP ) /2 f = 200 Hz
max
B HY
mT 2.5
B HY = B RP - B OP f = 200 Hz
max
0
typ
typ 1.5 min
-1
min
0.5
-2 -50
0
50
100
C
200
0 -50
0
50
100
C
200
Ta
Ta
Minimum Switching Field versus Frequency
3.0
AED01708
Minimum Switching Field versus Frequency
3.5
AED01709
B min mT
2.5
C = 940 nF
B min
mT 3.0 2.5
C = 940 nF
2.0
2.0
1.5
1.5
1.0
Ta = -40 C
Ta = 170 C
1.0 0.5 0 0.001
0.5
Ta = 25 C
Ta = 150 C
0 0.001
0.01
0.1
1
kHz
100
0.01
0.1
1
kHz
100
f
f
Semiconductor Group
15
1998-07-31
TLE 4921-3U
Delay Time1) between Switching Threshold B and Falling Edge of VQ at Tj = 25 C
30
AED01710
Delay Time1) between Switching Threshold B and Rising Edge of VQ at Tj = 25 C
30
AED01711
t dop s
25
BOP
t drp s
B RP t drp
t dop
25
20
20
15
B = 1.2 mT
15 B = 1.2 mT 10
10 B = 5 mT 5
5
B = 5 mT
0
0
0
5
10
15
kHz
25
0
5
10
15
kHz
25
f
f
Delay Time1) versus Differential Field
30
AED01712
Delay Time1) versus Temperature
30
AED01713
t d s
25
f = 10 kHz
t d s
25
f = 10 kHz B = 2 mT
20
20
t d op
15
15
10
10
t d op
5
t d rp
5
t d rp
0
0
20
40
60
mT B
100
0 -50
0
50
100
C
200
Ta
1)
Switching points related to initial measurement @B = 2 mT, f = 200 Hz
Semiconductor Group
16
1998-07-31
TLE 4921-3U
Rise and Fall Time versus Temperature
AED01714
Rise and Fall Time versus Output Current
120
AED01715
t
100 ns 90 80 70 60 50 40 30 20 10 0 -50 0
t
ns 100
Q = 40 mA
Ta = 25 C
80
tf tr
60
tr
40
tf
20
50
100
C
200
0
0
10
20
30
mA
50
Ta
Q
Capacitor Voltage versus Temperature
AED01716
Switching Thresholds versus Mechanical Stress
1.0 mT 0.9
AED01717
3.0
VC
V 2.5 B RP ,(- B OP )
F
r = 0.5
2.0 typ 1.5
0.8 max min 0.7
1.0
0.6
0.5
0 -50
0
50
100
C
200
0.5
0
1
2
3
N
5
Ta
F
Semiconductor Group
17
1998-07-31
TLE 4921-3U
Filter Sensitivity versus Temperature
AED01718
Filter Input Resistance versus Temperature
RC R C (25 C)
2
AED01719
-5
S C mV mT
-4 typ -3
VS = 12 V
1.5 max min 1
-2
0.5
-1
0 -50
0
50
100
C
200
0 -50
0
50
100
C
200
Ta
Ta
Delay Time for Power on (VS Switching from 0 V to 4.5 V) tpon versus Temperature
0.4 k ms nF 0.3
AED01720
t p on = k x C F
max
min 0.2
0.1
VC
t p on
0 -50 0 50 100 C 200
Ta
Semiconductor Group
18
1998-07-31
TLE 4921-3U
Package Outline P-SSO-4-1 (Plastic Single Small Outline Package)
Sorts of Packing Package outlines for tubes, trays etc. are contained in our Data Book "Package Information". Semiconductor Group 19
Dimensions in mm 1998-07-31
GPO05358

▲Up To Search▲

Price & Availability of TLE4921-3U

	To Download TLE4921-3U Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .